Journal articles: 'Surface lattice modes'

1

Horváth, I. "Surface modes and parity violation in Schwinger model on the lattice." Nuclear Physics B - Proceedings Supplements 47, no. 1-3 (March 1996): 683–86. http://dx.doi.org/10.1016/0920-5632(96)00150-8.

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Lin, Zo-Han, Jyun-Hong Pan, and Hung-Yuan Li. "Mechanical Strength of Triply Periodic Minimal Surface Lattices Subjected to Three-Point Bending." Polymers 14, no. 14 (July 16, 2022): 2885. http://dx.doi.org/10.3390/polym14142885.

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Sandwich panel structures (SPSs) with lattice cores can considerably lower material consumption while simultaneously maintaining adequate mechanical properties. Compared with extruded lattice types, triply periodic minimal surface (TPMS) lattices have light weight but better controllable mechanical properties. In this study, the different types of TPMS lattices inside an SPS were analysed comprehensively. Each SPS comprised two face sheets and a core filled with 20×5×1 TPMS lattices. The types of TPMS lattices considered included the Schwarz primitive (SP), Scherk’s surface type 2 (S2), Schoen I-graph-wrapped package (I-WP), and Schoen face-centred cubic rhombic dodecahedron (F-RD). The finite element method was applied to determine the mechanical performance of different TPMS lattices at different relative densities inside the SPS under a three-point bending test, and the results were compared with the values calculated from analytical equations. The results showed a difference of less than 21% between the analytical and numerical results for the deformation. SP had the smallest deformation among the TPMS lattices, and F-RD can withstand the highest allowable load. Different failure modes were proposed to predict potential failure mechanisms. The results indicated that the mechanical performances of the TPMS lattices were mainly influenced by the lattice geometry and relative density.

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Song, Daohong, Cibo Lou, Liqin Tang, Zhuoyi Ye, Jingjun Xu, and Zhigang Chen. "Experiments on Linear and Nonlinear Localization of Optical Vortices in Optically Induced Photonic Lattices." International Journal of Optics 2012 (2012): 1–10. http://dx.doi.org/10.1155/2012/273857.

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We provide a brief overview on our recent experimental work on linear and nonlinear localization of singly charged vortices (SCVs) and doubly charged vortices (DCVs) in two-dimensional optically induced photonic lattices. In the nonlinear case, vortex propagation at the lattice surface as well as inside the uniform square-shaped photonic lattices is considered. It is shown that, apart from the fundamental (semi-infinite gap) discrete vortex solitons demonstrated earlier, the SCVs can self-trap into stable gap vortex solitons under the normal four-site excitation with a self-defocusing nonlinearity, while the DCVs can be stable only under an eight-site excitation inside the photonic lattices. Moreover, the SCVs can also turn into stable surface vortex solitons under the four-site excitation at the surface of a semi-infinite photonics lattice with a self-focusing nonlinearity. In the linear case, bandgap guidance of both SCVs and DCVs in photonic lattices with a tunable negative defect is investigated. It is found that the SCVs can be guided at the negative defect as linear vortex defect modes, while the DCVs tend to turn into quadrupole-like defect modes provided that the defect strength is not too strong.

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Yu, Yang, and Yilun Liu. "Lattice-Boltzmann Models Simulation of Wetting Modes on the Surface with Nanostructures." Journal of Computational and Theoretical Nanoscience 5, no. 7 (July 1, 2008): 1377–80. http://dx.doi.org/10.1166/jctn.2008.2576.

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5

Xie, S. J., J. S. Han, X. D. Ma, L. M. Mei, and D. L. Lin. "Lattice-Vibration Localization in Doped Polythiophene." International Journal of Modern Physics B 11, no. 04n05 (February 20, 1997): 669–81. http://dx.doi.org/10.1142/s021797929700037x.

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Vibration modes around bipolarons in polythiophene are investigated numerically by considering a chain of finite length with different boundary conditions within the framework of tight-binding model. When the periodic boundary condition is applied, we find seven localized modes, among which three are of even parity and four of odd parity. One of the even modes is due solely to the influence of sulfur heteroatom in the heterocycle and is believed to be responsible for the mode around 700 cm -1 observed in the Raman spectrum of polythiophene. The dependence of intensities of these localized modes on the chain length is also investigated. When the ends of the chain are left open, it is shown that new surface modes are created from the highest optical branch. These modes may be identified as the high-frequency modes observed in infrared active vibration and resonant Raman scattering absorption experiments.

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Golo, V. L. "Phonon modes at the reconstructed surface of a cubic lattice." Journal of Physics: Condensed Matter 2, no. 46 (November 19, 1990): 9025–40. http://dx.doi.org/10.1088/0953-8984/2/46/004.

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7

LEE, M. B., B. G. FREDERICK, and G. APAI. "DIPOLE ACTIVITY AND POLARISATION OF SURFACE PHONONS IN THIN IONIC FILMS." Surface Review and Letters 01, no. 04 (December 1994): 635–39. http://dx.doi.org/10.1142/s0218625x94000837.

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Surface phonon spectra in ultrathin α- Al 2 O 3 films prepared on metallic substrates show excitation of modes in the frequency range of the surface dipole forbidden ω_-branches according to the dielectric theory of EELS. We compare calculations of the z-polarisation of the FuchsKliewer modes based on lattice dynamics with dielectric theory and semi-microscopic results for a simple NaCl lattice type thin film in the limit of k→0 appropriate to the dipolar-scattering regime. The form of the primary-beam-energy-dependence of the ω_-branch in thin α- Al 2 O 3 films is similar to the lattice dynamics prediction but is of much greater intensity. While the strong k-dependence may be attributed in part to significant z-polarisation of the ω_-branch, mixing with microscopic surface modes seems likely.

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8

Shi, Yunjie, Wei Liu, Shidi Liu, Tianyu Yang, Yuming Dong, Degui Sun, and Guangyuan Li. "Strong Coupling between Plasmonic Surface Lattice Resonance and Photonic Microcavity Modes." Photonics 9, no. 2 (February 1, 2022): 84. http://dx.doi.org/10.3390/photonics9020084.

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We report the strong coupling between plasmonic surface lattice resonances (SLRs) and photonic Fabry-Pérot (F-P) resonances in a microcavity embedded with two-dimensional periodic array of metal-insulator-metal nanopillars. For such a plasmonic-photonic system, we show that the SLR can be strongly coupled to the F-P resonances of both the odd- and even orders, and that the splitting energy reaches as high as 153 meV in the visible regime. Taking advantage of the strong coupling, the resulted high-energy upper polariton has similar characteristics as the plasmonic SLR, but the quality factor is almost twice of that of the SLR. We expect that this work will provide a new scheme for strong coupling between plasmonic and photonic modes, and will point to a new direction to improve the quality factor of SLRs.

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9

Juodėnas, Mindaugas, Domantas Peckus, Tomas Tamulevičius, Yusuke Yamauchi, Sigitas Tamulevičius, and Joel Henzie. "Effect of Ag Nanocube Optomechanical Modes on Plasmonic Surface Lattice Resonances." ACS Photonics 7, no. 11 (October 20, 2020): 3130–40. http://dx.doi.org/10.1021/acsphotonics.0c01187.

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10

Tobing, Landobasa Y. M., Alana M. Soehartono, Aaron D. Mueller, Ken-Tye Yong, Weijun Fan, and Dao Hua Zhang. "Hybridized surface lattice modes in intercalated 3-disk plasmonic crystals for high figure-of-merit plasmonic sensing." Nanoscale 13, no. 7 (2021): 4092–102. http://dx.doi.org/10.1039/d0nr07020c.

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11

Zhou, Renlong, Guozheng Nie, Lingxi Wu, Qiong Liu, Suxia Xie, Mengxiong Wu, Lisan Zeng, and Yingyi Xiao. "Second-Order Nonlinearity Assisted by Dual Surface Plasmon Resonance Modes in Perforated Gold Film." Journal of Nanomaterials 2014 (2014): 1–7. http://dx.doi.org/10.1155/2014/252950.

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We have studied analytically the reflection assisted with surface plasmon through the square lattice perforated gold film. Under the excitation of the external electromagnetic field with one or two different frequencies, the second-order nonlinearity exists in this noncentrosymmetric metal-based metamaterial. We employed the two surface plasmon resonances modes with different lattice periods. With the excitation of two different plasmon resonances modes, the strong local field induces an expected increase of the second-order nonlinearity including second harmonic generation as well as the sum (difference) frequency generation. The field distributions results also indicate that the enhancement of sum frequency signals and difference frequency signals strongly depends on surface plasmon resonance effect.

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12

Chen, Shumei, Bernhard Reineke, Guixin Li, Thomas Zentgraf, and Shuang Zhang. "Strong Nonlinear Optical Activity Induced by Lattice Surface Modes on Plasmonic Metasurface." Nano Letters 19, no. 9 (August 16, 2019): 6278–83. http://dx.doi.org/10.1021/acs.nanolett.9b02417.

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13

Li, Chunyan, Ran Cui, Fangwei Ye, Yaroslav V. Kartashov, Lluis Torner, and Xianfeng Chen. "Self-deflecting plasmonic lattice solitons and surface modes in chirped plasmonic arrays." Optics Letters 40, no. 6 (March 4, 2015): 898. http://dx.doi.org/10.1364/ol.40.000898.

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14

Oshima, C. "New type of surface atomic vibrational modes of the (100) surface of the NaCl-type lattice." Physical Review B 34, no. 4 (August 15, 1986): 2949–51. http://dx.doi.org/10.1103/physrevb.34.2949.

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15

Booske, John H., Reid F. Cooper, and Ian Dobson. "Mechanisms for nonthermal effects on ionic mobility during microwave processing of crystalline solids." Journal of Materials Research 7, no. 2 (February 1992): 495–501. http://dx.doi.org/10.1557/jmr.1992.0495.

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Models for nonthermal effects on ionic motion during microwave heating of crystalline solids are considered to explain the anomolous reductions of activation energy for diffusion and the overall faster kinetics noted in microwave sintering experiments and other microwave processing studies. We propose that radiation energy couples into low (microwave) frequency elastic lattice oscillations, generating a nonthermal phonon distribution that enhances ion mobility and thus diffusion rates. Viewed in this manner, it is argued that the effect of the microwaves would not be to reduce the activation energy, but rather to make the use of a Boltzmann thermal model inappropriate for the inference of activation energy from sintering-rate or tracer-diffusion data. A highly simplified linear oscillator lattice model is used to qualitatively explore coupling from microwave photons to lattice oscillations. The linear mechanism possibilities include resonant coupling to weak-bond surface and point defect modes, and nonresonant coupling to zero-frequency displacement modes. Nonlinear mechanisms such as inverse Brillouin scattering are suggested for resonant coupling of electromagnetic and elastic traveling waves in crystalline solids. The models suggest that nonthermal effects should be more pronounced in polycrystalline (rather than single crystal) forms, and at elevated bulk temperatures.

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16

Chiang, Yen-Ju, Tsan-Wen Lu, Pin-Ruei Huang, Shih-Yen Lin, and Po-Tsung Lee. "MoS2 with Stable Photoluminescence Enhancement under Stretching via Plasmonic Surface Lattice Resonance." Nanomaterials 11, no. 7 (June 28, 2021): 1698. http://dx.doi.org/10.3390/nano11071698.

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In this study, by combining a large-area MoS2 monolayer with silver plasmonic nanostructures in a deformable polydimethylsiloxane substrate, we theoretically and experimentally studied the photoluminescence (PL) enhancement of MoS2 by surface lattice resonance (SLR) modes of different silver plasmonic nanostructures. We also observed the stable PL enhancement of MoS2 by silver nanodisc arrays under differently applied stretching strains, caused by the mechanical holding effect of the MoS2 monolayer. We believe the results presented herein can guarantee the possibility of stably enhancing the light emission of transition metal dichalcogenides using SLR modes in a deformable platform.

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17

Xu, Quan, Kang Xie, and Hua Jun Yang. "Self-Collimation in Square Lattice Two Dimensional Photonic Crystals with Ring-Shaped Holes." Applied Mechanics and Materials 110-116 (October 2011): 1024–29. http://dx.doi.org/10.4028/www.scientific.net/amm.110-116.1024.

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We demonstrate self-collimation phenomena based on a new type of photonic crystals made of square lattice with ring shaped holes. The plane wave expansion (PWE) method is used to get the three dimensional band diagram and equi-frequency of the second band which displays the self-collimation phenomena for the structure we proposed in this paper. The collimation angle is mainly depending on the maximum flatness half width (MFHW) of the equi-frequency. The FDTD method is employed to demonstrate the electric field amplitude distributions for the collimation phenomena. Partly, in order to achieve high efficient coupling of the input and output port, we modify both surface structures to modulate the wave-front to obtain desired effect. The parameter of the input surface is modified which will prevent the production of surface modes which takes away the EM power and enhance the transmittance. For a square lattice with the modified parameters at each side of the input surface, the surface modes are suppressed to couple with the continuum of the dielectric waveguide modes. More importantly, they might have potential application in integrated optical circuits.

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18

TONG, S. Y., Y. CHEN, K. P. BOHNEN, T. RODACH, and K. M. HO. "THE STRUCTURE AND LATTICE DYNAMICS OF UNRECONSTRUCTED FCC (001) AND (111) METAL SURFACES." Surface Review and Letters 01, no. 01 (June 1994): 97–107. http://dx.doi.org/10.1142/s0218625x94000126.

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Progress in first-principles surface phonon calculation and multiple scattering phonon cross-section calculation has provided a more complete understanding of the localized vibrational modes on unreconstructed metal surfaces. A discussion of some of the new results is given focusing on how the new information resolves earlier difficulties in the interpretation of inelastic He-atom scattering (HAS) and high-resolution electron energy loss spectroscopy (EELS) data on these metal surfaces.

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19

Sufiiarov, Vadim, Artem Kantyukov, Anatoliy Popovich, and Anton Sotov. "Synthesis of Spherical Powder of Lead-Free BCZT Piezoceramics and Binder Jetting Additive Manufacturing of Triply Periodic Minimum Surface Lattice Structures." Materials 15, no. 18 (September 9, 2022): 6289. http://dx.doi.org/10.3390/ma15186289.

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The article presents the results of the synthesis of lead-free piezoceramic materials (Ba0.9Ca0.1)(Ti0.9Zr0.1)O3 (BCZT system) in spherical powder form and their subsequent application in the binder jetting additive manufacturing process. Green models were manufactured using this powder material with binder jetting, different sintering modes were investigated, and the functional piezoelectric properties were measured. Lattice structures with triply periodic minimum surface topologies, such as Gyroid and Schwarz, were designed and manufactured. It is shown that the functional properties of lattice structures depend on the parameters of the cells and the chosen topology.

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20

Novozhilov, Vasily B., Boris V. Lidskii, and Vladimir S. Posvyanskii. "Different Modes of Combustion Wave on a Lattice Burner." Mathematics 10, no. 15 (August 2, 2022): 2731. http://dx.doi.org/10.3390/math10152731.

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The stabilization of a planar premixed flame front on a lattice (porous) burner is considered. The developed model captures all the important features of the phenomenon, while also admitting qualitative analytical investigation. It has been rigorously mathematically proven that there exist two different stabilization regimes: one with flame front located nearby the surface of the burner, and another with the flame front located inside the lattice. These two regimes result in qualitatively different gas temperature profiles along the flow that is monotonic and non-monotonic, respectively. The boundary between the two regimes is described in terms of dependence of the lattice solid material temperature on flow Peclet number. With similar temperature profiles, such dependencies may be both monotonic and non-monotonic. The transition between the two types of dependencies is controlled by the Arrhenius number. Conclusions of the study are supported by numerical analysis. They also compare favorably with the available experimental data. The novelty of the present approach is a fundamentally rigorous analytical analysis of the problem. The proposed analytical model, based on δ-function approximation of the chemical source term, agrees well (within 7% relative error) with the model based on the distributed description of the chemical reaction zone. The obtained results are important from both a theoretical and practical point of view. They demonstrate the existence of the two qualitatively different operating regimes for lattice burners, thus impacting design solutions for such devices. The results will be of great interest to the broader academic community, particularly in research areas where similar wave structures may emerge.

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Schraad, M. W., and N. Triantafyllidis. "Scale Effects in Media With Periodic and Nearly Periodic Microstructures, Part II: Failure Mechanisms." Journal of Applied Mechanics 64, no. 4 (December 1, 1997): 763–71. http://dx.doi.org/10.1115/1.2788980.

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Using the nonlinearly elastic planar lattice model presented in Part I, the influence of scale (i.e., the size of the representative volume, relative to the size of the unit cell) on the onset of failure in periodic and nearly periodic media is investigated. For this study, the concept of a microfailure surface is introduced—this surface being defined as the locus of first instability points found along radial load paths through macroscopic strain space. The influence of specimen size and microstructural imperfections (both geometric and constitutive) on these failure surfaces is investigated. The microfailure surface determined for the infinite model with perfectly periodic microstructure, is found to be a lower bound for the failure surfaces of perfectly periodic, finite models, and an upper bound for the failure surfaces of finite models with microstructural imperfections. The concept of a macrofailure surface is also introduced—this surface being defined as the locus of points corresponding to the loss of ellipticity in the macroscopic (homogenized) moduli of the model. The macrofailure surface is easier to construct than the microfailure surface, because it only requires calculation of the macroscopic properties for the unit cell, at each loading state along the principal equilibrium path. The relation between these two failure surfaces is explored in detail, with attention focused on their regions of coincidence, which are of particular interest due to the possible development of macroscopically localized failure modes.

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RAFIL, O., A. LALAOUI, M. TAMINE, and A. KHELIFI. "VIBRATIONAL PROPERTIES OF TWO ISOLATED STEPS: A THEORETICAL MODEL." Surface Review and Letters 09, no. 03n04 (June 2002): 1387–94. http://dx.doi.org/10.1142/s0218625x02003986.

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We investigate the dynamical properties of two isolated steps on the surface. We present the solution of the full dynamical problem arising from the absence of translation symmetry in two dimensions due to extended surface steps on the surface boundary of an insulating substrate. The calculations concern in particular the dynamics of localized modes of an atomic step on the surface of a cubic lattice. The theoretical approach determines the vibrational field in both steps. The matching method, which constitutes a powerful formalism for determining the vibrational properties of such disordered surfaces, is used. The model presented in this study consists of two monatomic steps as the interface between three coupled semi-infinite and single semi-infinite atomic layers. The dynamical properties of the perfect waveguides are presented and calculated numerically. The breakdown of translational symmetry perpendicular to the step edges gives rise to several Raleigh-like branches localized in the neighborhood of the steps. Typical dispersion curves for these modes along the steps are given with their polarization.

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23

Cen, Mengjia, Jiawei Wang, Jianxun Liu, Ye Li, Wenfeng Cai, Delai Kong, Dan Luo, Tun Cao, and Yan Jun Liu. "Plasmonic Surface Lattice Resonances in Suspended Symmetric Double-Layer Gratings." Photonics 9, no. 12 (November 22, 2022): 890. http://dx.doi.org/10.3390/photonics9120890.

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Surface lattice resonances (SLRs) with high-quality factors supported by metal nanoparticle arrays are useful for plasmonic nanolasers, biochemical sensors, and surface-enhanced Raman spectroscopy. Most nanoparticle arrays are fabricated on a substrate, and the refractive index mismatch between the substrate and superstrate suppresses the performance of SLRs. In this work, we propose unique SLRs excited in suspended, self-aligned symmetric double-layer gratings with index-matched environment. The self-aligned double-layer gratings are fabricated using a single-step electron beam lithography and exhibit a Fano-like spectra resulting from interference between out-of-plane plasmonic resonances and diffraction modes. By changing the incident angle and refractive index of the surrounding medium, the SLRs can be tuned from visible to near-infrared regions with a high-quality factor of 120.

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Kukta, R., A. Peralta, and D. Kouris. "Surface Steps: From Atomistics to Continuum." Journal of Applied Mechanics 69, no. 4 (June 20, 2002): 443–50. http://dx.doi.org/10.1115/1.1468999.

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The elastic interaction between surface steps biases growth and can have a dominant influence on growth modes of thin films. A new continuum solution is presented that takes into account the actual geometry of the steps. It is shown that even in the absence of external stress, the interaction energy contains a logarithmic dependence not previously reported in the literature. This additional term is of the same order of magnitude as the ones contained in the solution of Marchenko and Parshin that has been generally used during the past twenty years. Opposite and similar steps are investigated and closed-form expressions for the relevant elastic fields and interaction energies are derived. Results compare favorably with the ones obtained from embedded atom method (EAM) simulations and a recent elastic lattice model.

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Deng, Shikai, Ran Li, Jeong-Eun Park, Jun Guan, Priscilla Choo, Jingtian Hu, Paul J. M. Smeets, and Teri W. Odom. "Ultranarrow plasmon resonances from annealed nanoparticle lattices." Proceedings of the National Academy of Sciences 117, no. 38 (September 8, 2020): 23380–84. http://dx.doi.org/10.1073/pnas.2008818117.

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This paper reports how the spectral linewidths of plasmon resonances can be narrowed down to a few nanometers by optimizing the morphology, surface roughness, and crystallinity of metal nanoparticles (NPs) in two-dimensional (2D) lattices. We developed thermal annealing procedures to achieve ultranarrow surface lattice resonances (SLRs) with full-width at half-maxima linewidths as narrow as 4 nm from arrays of Au, Ag, Al, and Cu NPs. Besides annealing, we developed a chemical vapor deposition process to use Cu NPs as catalytic substrates for graphene growth. Graphene-encapsulated Cu NPs showed the narrowest SLR linewidths (2 nm) and were stable for months. These ultranarrow SLR nanocavity modes supported even narrower lasing emission spectra and high nonlinearity in the input–output light–light curves.

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Wang, Xiaowei, Leonard C. Kogos, and Roberto Paiella. "Giant distributed optical-field enhancements from Mie-resonant lattice surface modes in dielectric metasurfaces." OSA Continuum 2, no. 1 (December 17, 2018): 32. http://dx.doi.org/10.1364/osac.2.000032.

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Shams Mousavi, S. Hamed, Robert Lemasters, Feng Wang, Ali Eshaghian Dorche, Hossein Taheri, Ali A. Eftekhar, Hayk Harutyunyan, and Ali Adibi. "Phase-matched nonlinear second-harmonic generation in plasmonic metasurfaces." Nanophotonics 8, no. 4 (February 7, 2019): 607–12. http://dx.doi.org/10.1515/nanoph-2018-0181.

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AbstractThe phase matching between the propagating fundamental and nonlinearly generated waves plays an important role in the efficiency of the nonlinear frequency conversion in macroscopic crystals. However, in nanoscale samples, such as nanoplasmonic structures, the phase-matching condition is often ignored due to the sub-wavelength nature of the materials. Here, we first show that the phase matching of the lattice plasmon modes at the fundamental and second-harmonic frequencies in a plasmonic nanoantenna array can effectively enhance the surface-enhanced second-harmonic generation. Additionally, a significant enhancement of the second-harmonic generation is demonstrated using stationary band-edge lattice plasmon modes with zero phase.

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Huang, Yu-Hsun, Zi-Xian Yang, Su-Ling Cheng, Chien-Hung Lin, Gray Lin, Kien-Wen Sun, and Chien-Ping Lee. "Effect of Hole Shift on Threshold Characteristics of GaSb-Based Double-Hole Photonic-Crystal Surface-Emitting Lasers." Micromachines 12, no. 5 (April 21, 2021): 468. http://dx.doi.org/10.3390/mi12050468.

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Photonic-crystal (PC) surface-emitting lasers (SELs) with double-hole structure in the square-lattice unit cell were fabricated on GaSb-based type-I InGaAsSb/AlGaAsSb heterostructures. The relative shift of two holes was varied within one half of the lattice period. We measured the lasing wavelengths and threshold pumping densities of 16 PC-SELs and investigated their dependence on the double-hole shift. The experimental results were compared to the simulated wavelengths and threshold gains of four band-edge modes. The measured lasing wavelength did not exhibit switching of band-edge mode; however, the calculated lowest threshold mode switched as the double-hole shift exceeded one quarter of the lattice period. The identification of band-edge lasing mode revealed that modal gain discrimination was dominated over by its mode wavelength separation.

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Li, Zong-Lin, Shen-Chieh Lin, Gray Lin, Hui-Wen Cheng, Kien-Wen Sun, and Chien-Ping Lee. "Effect of Etching Depth on Threshold Characteristics of GaSb-Based Middle Infrared Photonic-Crystal Surface-Emitting Lasers." Micromachines 10, no. 3 (March 14, 2019): 188. http://dx.doi.org/10.3390/mi10030188.

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We study the effect of etching depth on the threshold characteristics of GaSb-based middle infrared (Mid-IR) photonic-crystal surface-emitting lasers (PCSELs) with different lattice periods. The below-threshold emission spectra are measured to identify the bandgap as well as band-edge modes. Moreover, the bandgap separation widens with increasing etching depth as a result of enhanced diffraction feedback coupling. However, the coupling is nearly independent of lattice period. The relationship between threshold gain and Bragg detuning is also experimentally determined for PCSELs and is similar to that calculated theoretically for one-dimensional distributed feedback lasers.

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Liu, Jianxi, Weijia Wang, Danqing Wang, Jingtian Hu, Wendu Ding, Richard D. Schaller, George C. Schatz, and Teri W. Odom. "Spatially defined molecular emitters coupled to plasmonic nanoparticle arrays." Proceedings of the National Academy of Sciences 116, no. 13 (March 8, 2019): 5925–30. http://dx.doi.org/10.1073/pnas.1818902116.

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This paper describes how metal–organic frameworks (MOFs) conformally coated on plasmonic nanoparticle arrays can support exciton–plasmon modes with features resembling strong coupling but that are better understood by a weak coupling model. Thin films of Zn-porphyrin MOFs were assembled by dip coating on arrays of silver nanoparticles (NP@MOF) that sustain surface lattice resonances (SLRs). Coupling of excitons with these lattice plasmons led to an SLR-like mixed mode in both transmission and transient absorption spectra. The spectral position of the mixed mode could be tailored by detuning the SLR in different refractive index environments and by changing the periodicity of the nanoparticle array. Photoluminescence showed mode splitting that can be interpreted as modulation of the exciton line shape by the Fano profile of the surface lattice mode, without requiring Rabi splitting. Compared with pristine Zn-porphyrin, hybrid NP@MOF structures achieved a 16-fold enhancement in emission intensity. Our results establish MOFs as a crystalline molecular emitter material that can couple with plasmonic structures for energy exchange and transfer.

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31

Hull, R., J. Gray, C. C. Wu, S. Atha, and J. A. Floro. "Interaction between surface morphology and misfit dislocations as strain relaxation modes in lattice-mismatched heteroepitaxy." Journal of Physics: Condensed Matter 14, no. 48 (November 22, 2002): 12829–41. http://dx.doi.org/10.1088/0953-8984/14/48/323.

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32

Shapiro, M. A., K. R. Samokhvalova, J. R. Sirigiri, R. J. Temkin, and G. Shvets. "Simulation of the bulk and surface modes supported by a diamond lattice of metal wires." Journal of Applied Physics 104, no. 10 (November 15, 2008): 103107. http://dx.doi.org/10.1063/1.3021310.

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33

Luo, Xiaoqing, Xiaoxiang Dong, Xinlong Xu, Fangrong Hu, and Guangyuan Li. "Narrowband terahertz metasurface circular polarization beam splitter with large spectral tunability based on lattice-induced chirality." Journal of Physics D: Applied Physics 55, no. 10 (December 9, 2021): 105109. http://dx.doi.org/10.1088/1361-6463/ac3e2b.

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Abstract We propose a terahertz metasurface with chirality induced by surface lattice resonance to create a narrowband circular polarization beam splitter (PBS) with large spectral tunability in both transmission and reflection modes. Results show that strong circular dichroism effects can be observed in two spectrally narrow bands, and thus a dual-band circular PBS can be achieved. We show that surface lattice resonance induces much narrower and stronger circular dichroism effects than localized resonance, resulting in higher polarization extinction ratios, higher quality factors, and more circular polarization states. The narrowband operation frequency of lattice-induced PBS with extinction ratio larger than 10 dB can be tuned over a large spectral range, from 1.6 THz to 2.3 THz, by varying the incidence angle. We expect the proposed strong, narrowband, and spectrally tunable circular PBS will find applications in polarization-dependent systems including imaging, spectroscopy, sensing and telecommunication in the terahertz regime.

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Yang, Quanxin, Bin Zhang, Yuanbo Li, Xuping Wang, Feng Chen, Pengfei Wu, and Hongliang Liu. "Femtosecond Laser Induced Lattice Deformation in KTN Crystal." Micromachines 13, no. 12 (November 30, 2022): 2120. http://dx.doi.org/10.3390/mi13122120.

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In recent years, many novel optical phenomena have been discovered based on perovskite materials, but the practical applications are limited because of the difficulties of device fabrication. Here, we propose a method to directly induce localized lattice modification inside the potassium tantalate niobate crystal by using the femtosecond laser. This selective modification at the processed regions and the surrounding areas is characterized by two-dimensional Raman spectrum mapping. The spectrum variations corresponding to specific lattice vibration modes demonstrate the lattice structure deformation. In this way, the lattice expansion at the femtosecond laser irradiated regions and the lattice compression at the surrounding areas are revealed. Furthermore, surface morphology measurement confirms this lattice expansion and suggests the extension of lattice structure along the space diagonal direction. Moreover, the existence of an amorphization core is revealed. These modifications on the sample lattice can induce localized changes in physicochemical properties; therefore, this method can realize the fabrication of both linear diffraction and nonlinear frequency conversion devices by utilizing the novel optical responses of perovskite materials.

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Hu, Jinyong, Chuxuan Tan, Wangdi Bai, Yiming Li, Qi Lin, and Lingling Wang. "Dielectric nanocavity-coupled surface lattice resonances for high-efficiency plasmonic sensing." Journal of Physics D: Applied Physics 55, no. 7 (November 9, 2021): 075105. http://dx.doi.org/10.1088/1361-6463/ac31f2.

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Abstract Surface lattice resonances (SLRs) arising in metal nanostructure arrays have shown tremendous application prospects in the field of plasmonic biosensing. However, these SLRs still suffer from poor optical properties, such as broad linewidth or weak resonance intensity that is especially excited under normal incidence and asymmetric environments, which hinder further practical applications. Herein, we theoretically propose an effective strategy to tailor the SLRs performance of metal nanostructure arrays by introducing a dielectric nanocavity. Originating from the strong interference between the in-plane lattice resonance mode and plasmonic gap cavity modes, the dielectric nanocavity-mediated gold nanostructure arrays exhibit both narrow spectral features with a linewidth of ∼8.2 nm and strong resonance intensity with absorbance amplitude exceeding 95%, even though under normal incidence and asymmetric environment excitation. The simulation results then show that the sensitivity and the figure of merit can reach up to 527.5 nm RIU−1 and 64.3, respectively, as for plasmonic refractive index sensing. This work not only paves the way toward the achievement of effective control of in-plane SLRs, but also provides a potentially attractive candidate for the development of high-efficiency plasmonic sensors.

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Johnson, S. L., P. Beaud, E. Vorobeva, C. J. Milne, É. D. Murray, S. Fahy, and G. Ingold. "Non-equilibrium phonon dynamics studied by grazing-incidence femtosecond X-ray crystallography." Acta Crystallographica Section A Foundations of Crystallography 66, no. 2 (February 9, 2010): 157–67. http://dx.doi.org/10.1107/s0108767309053859.

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The timescales for structural changes in a single crystal of bismuth after excitation with an intense near-infrared laser pulse are studied with femtosecond pump-probe X-ray diffraction. Changes in the intensity and reciprocal-lattice vector of several reflections give quantitative information on the structure factor and lattice strain as a function of time, with a resolution of 200 fs. The results indicate that the majority of excess carrier energy that remains near the surface is transferred to vibrational modes on a timescale of about 10 ps, and that the resultant increase in the variance of the atomic positions at these times is consistent with the overall magnitude of lattice strain that develops.

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Proscia, Nicholas V., Robert J. Collison, Carlos A. Meriles, and Vinod M. Menon. "Coupling of deterministically activated quantum emitters in hexagonal boron nitride to plasmonic surface lattice resonances." Nanophotonics 8, no. 11 (September 17, 2019): 2057–64. http://dx.doi.org/10.1515/nanoph-2019-0136.

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AbstractThe cooperative phenomena stemming from the radiation field-mediated coupling between individual quantum emitters are presently attracting broad interest for applications related to on-chip photonic quantum memories and long-range entanglement. Common to these applications is the generation of electro-magnetic modes over macroscopic distances. Much research, however, is still needed before such systems can be deployed in the form of practical devices, starting with the investigation of alternate physical platforms. Quantum emitters in two-dimensional (2D) systems provide an intriguing route because these materials can be adapted to arbitrarily shaped substrates to form hybrid systems wherein emitters are near-field-coupled to suitable optical modes. Here, we report a scalable coupling method allowing color center ensembles in a van der Waals material (hexagonal boron nitride) to couple to a delocalized high-quality plasmonic surface lattice resonance. This type of architecture is promising for photonic applications, especially given the ability of the hexagonal boron nitride emitters to operate as single-photon sources at room temperature.

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BELHADI, MEHAND, and ANTOINE KHATER. "SPIN WAVE MODES AND MAGNON SCATTERING AT SURFACE NANOSTRUCTURE ON 2D HEISENBERG FERROMAGNETS." Surface Review and Letters 11, no. 01 (February 2004): 99–109. http://dx.doi.org/10.1142/s0218625x04005962.

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We investigate the spin fluctuation dynamics and the scattering phenomena at adsorbed magnetic nanostructure on the surface of two-dimensional Heisenberg ferromagnets. The surface is considered as an infinite slab of two coupled atomic layers, and the nanostructure as an isolated monatomic chain on the surface of a cubic lattice. No electronic effects are considered but local changes in exchange fields between the localized spins of the nanostructure and the magnetically ordered substrate are assumed to be dominant. The mathematical framework of the matching method is used to analyze both the localization and the scattering phenomena at the nanostructure boundaries. The energy of spin wave localized modes arising from the absence of magnetic translation symmetry is determined. The transmission and reflection probabilities as well as the spin wave average transmittance across the nanostructure are calculated and numerical results are presented in a large range of scattering energies. It is shown that there are several localized spin wave modes associated with the nanostructure which may be either optical or acoustical modes (depending on the system parameters), and the coherent coupling between these localized spin modes and the propagating spin modes of the system leads to Fano resonances in the scattering spectra.

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Wahab, Hilal S., and Andreas D. Koutselos. "Comparative Study of the Adsorption of Aromatic Pollutants onto TiO2 (100) Surface via Molecular Simulation." Australian Journal of Chemistry 64, no. 12 (2011): 1611. http://dx.doi.org/10.1071/ch10288.

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The adsorption mode of benzoic acid onto the anatase TiO2 (100) surface has been studied through the semi-empirical self-consistent field molecular orbital method MSINDO and is compared with previously determined modes of four aromatic compounds: chlorobenzene, aniline, p-chlorophenol and nitrobenzene. The simulation results reveal that aniline and p-chlorophenol molecules are adsorbed with their aromatic ring positioned parallel to the surface although they are linked to a surface lattice titanium atom via the amino nitrogen and phenolic oxygen respectively. In contrast, chlorobenzene, nitrobenzene and benzoic acid are found in perpendicular configurations and they are attached to the surface via the chlorine and oxygen atoms of the NO2 and COOH groups respectively. The calculated substrate–surface interaction energy is influenced by the degree of basicity of the lone pair of the donating atoms, the number of linkages between the substrate and the surface and, further, the hydrogen bonding between the acidic hydrogen and lattice oxygen atom. The computed vibrational density of states for these adsorbed organic pollutants is in reasonably good agreement with available experimental data and previous theoretical results.

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Rodríguez-Álvarez, Javier, Lorenzo Gnoatto, Marc Martínez-Castells, Albert Guerrero, Xavier Borrisé, Arantxa Fraile Rodríguez, Xavier Batlle, and Amílcar Labarta. "An Inverted Honeycomb Plasmonic Lattice as an Efficient Refractive Index Sensor." Nanomaterials 11, no. 5 (May 4, 2021): 1217. http://dx.doi.org/10.3390/nano11051217.

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We present an efficient refractive index sensor consisting of a heterostructure that contains an Au inverted honeycomb lattice as a main sensing element. Our design aims at maximizing the out-of-plane near-field distributions of the collective modes of the lattice mapping the sensor surroundings. These modes are further enhanced by a patterned SiO2 layer with the same inverted honeycomb lattice, an SiO2 spacer, and an Au mirror underneath the Au sensing layer that contribute to achieving a high performance. The optical response of the heterostructure was studied by numerical simulation. The results corresponding to one of the collective modes showed high sensitivity values ranging from 99 to 395 nm/RIU for relatively thin layers of test materials within 50 and 200 nm. In addition, the figure of merit of the sensor detecting slight changes of the refractive index of a water medium at a fixed wavelength was as high as 199 RIU−1. As an experimental proof of concept, the heterostructure was manufactured by a simple method based on electron beam lithography and the measured optical response reproduces the simulations. This work paves the way for improving both the sensitivity of plasmonic sensors and the signal of some enhanced surface spectroscopies.

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Fei, Tianhao, Tao Cheng, Lei Zhang, Jingyi Zhang, Jia-Yue Yang, and Linhua Liu. "Temperature-dependent infrared dielectric functions and hybrid phonon-polaritons in wurtzite GaN: A spectroscopic ellipsometry and multiscale simulation study." Journal of Applied Physics 131, no. 9 (March 7, 2022): 093102. http://dx.doi.org/10.1063/5.0084447.

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Polar wurtzite GaN can host surface phonon-polaritons (SPHPs) along its bulk surface and achieve sub-diffraction confinement with an ultralow optical loss and has emerged as a relevant technological material for infrared nanophotonics. Yet, few studies have reported on the temperature-dependent infrared dielectric functions, lattice vibration's influence on the hybrid phonon-polaritons, and the underlying physics that are largely unexplored. Herein, we perform the infrared spectroscopic ellipsometry (SE) measurements and multiscale simulations including first-principles and finite-difference time-domain (FDTD) to systematically study the infrared dielectric function at varying temperatures, phonon dynamics, and SPHPs in wurtzite GaN. SE experiments identify the reststrahlen band where the amplitude of ordinary dielectric function reduces significantly by a factor of 3.5 and the propagation length of SPHPs decreases by a factor of 4.18 as temperature increases from 250 to 800 K, suggesting the strong influence of lattice vibration on SPHPs. First-principles calculations confirm that the reststrahlen band for the ordinary dielectric function lies between the transverse and longitudinal E1 phonon modes, while that of extraordinary dielectric function lies between the transverse and longitudinal A1 phonon modes. FDTD simulations observe the localized surface phonon resonances in the nano-porous GaN thin films deposited on the sapphire substrate only for the transverse magnetic wave mode, which is consistent with the observation of extra dip in the measured pp-polarized reflection spectroscopy. This work provides a deep insight into lattice vibration influence on phonon dynamics and SPHPs in wurtzite GaN and helps engineer them in nanophotonic devices toward achieving better performance.

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Wang, Ben-Xin, Qin Xie, Guangxi Dong, and Wei-Qing Huang. "Broadband terahertz perfect light absorber based on the modes of fundamental response and surface lattice resonance." OSA Continuum 1, no. 1 (September 12, 2018): 213. http://dx.doi.org/10.1364/osac.1.000213.

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Wu, Feng, Meibao Qin, and Shuyuan Xiao. "Quasi-bound state in the continuum supported by a compound grating waveguide structure for high-figure-of-merit refractive-index sensing." Journal of Applied Physics 132, no. 19 (November 21, 2022): 193101. http://dx.doi.org/10.1063/5.0120626.

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Herein, we realize quasi-bound states in the continuum (quasi-BICs) in a compound grating waveguide structure with a complex lattice. The first layer of the structure is a grating layer composed of two dielectric ridges with different heights and the same width, while the second layer of the structure is a dielectric waveguide layer supporting the guided mode. As the height difference in two dielectric ridges changes from a non-zero value to zero, the lattice of the structure turns from a complex lattice with the period [Formula: see text] to a simple lattice with the half of the previous period [Formula: see text]. Therefore, the previous excitable odd-order resonant guided modes cannot be excited and become BICs. Assisted by the ultra-high Q factor of the quasi-BIC, we achieve high-performance refractive-index sensing at near-infrared wavelengths. Under the proper design, the optimum sensitivity and figure of merit (FoM) reach 676.8 nm/RIU and 9543 RIU−1, respectively. Compared with the reported refractive-index sensors based on surface plasmon polaritons, localized surface plasmon resonances, and Bloch surface waves, the optimum sensitivity achieved in this work reaches the same order of magnitude, while the optimum FoM achieved in this work is one or two orders of magnitude higher. Our work reveals that quasi-BICs would become a powerful competitive mechanism to achieve high-performance refractive-index sensing.

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Xiong, Lei, Hong-Wei Ding, and Guang-Yuan Li. "Quadrupolar lattice plasmon modes induced by diffraction of high-quality factors in silver nanoparticle arrays." Acta Physica Sinica 71, no. 4 (2022): 047802. http://dx.doi.org/10.7498/aps.71.20211629.

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Periodic nanoparticle arrays with lower loss or high-quality (Q) factor resonances have made great advances in numerous applications. Such arrays can support narrow resonance modes by the hybridization of plasmonic-photonic modes, known as lattice plasmon modes (LPMs). The LPMs arise from the diffraction-induced coupling between localized surface plasmon resonances (LSPRs) of nanoparticles in symmetric or quasi-symmetric refractive index environment. To date, the great majority of researches have focused on the coupling of dipolar modes to in-plane orthogonal diffraction waves in nanoparticle arrays, resulting in dipolar lattice plasmon modes (DLPMs). However, there are few studies about quadrupolar lattice plasmon modes (QLPMs) for parallel coupling in symmetric environment, especially for high Q-factor QLPMs. In this work, we explore the sharp QLPMs of the silver nanodisk arrays by x-polarized light at normal incidence. In the first place, the scattering cross-section and near-field electric field distribution of single silver nanodisk indicate the existence of dipolar and quadrupolar LSPRs, thus, the optical responses of silver nanodisk arrays exhibit the peak-and-dip profiles of DLPMs and QLPMs at different wavelengths. Also, the electromagnetic field distributions confirm that the parallel propagating electric field introduces QLPM and results in electric field delocalization, while DLPM is existent in another way in periodic silver nanodisk arrays. Moreover, the position, linewidth and lineshape of the QLPM strongly depend on the role of lattice period. We enable these resonance modes to be selectively accessed and individually optimized by tuning lattice periods in the x- or y-direction. By changing the lattice period in the x-direction from 300 to 550 nm in steps of 50 nm, the dip of transmission intensity increases gradually, and when periods in the two directions are equal, the transmission dip exhibits a narrow-band QLPM resonance with a linewidth of 0.4 nm, corresponding quality factor is as high as Q = 1815 under the x-polarized light. In particular, by varying periods in the y-direction, the QLPM can also be manipulated in a range from an asymmetric Fano-like lineshape peak to a dip. The acquisition of these results may provide a design strategy for high-Q factor resonance in nanolaser, sensing, and nonlinear optics.

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R. Dadadzhanov, Daler, Tigran A. Vartanyan, and Alina Karabchevsky. "Lattice Rayleigh Anomaly Associated Enhancement of NH and CH Stretching Modes on Gold Metasurfaces for Overtone Detection." Nanomaterials 10, no. 7 (June 29, 2020): 1265. http://dx.doi.org/10.3390/nano10071265.

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Molecular overtones stretching modes that occupy the near-infrared (NIR) are weak compared to the fundamental vibrations. Here we report on the enhancement of absorption by molecular vibrations overtones via electromagnetic field enhancement of plasmonic nanoparallelepipeds comprising a square lattice. We explore numerically, using finite element method (FEM), gold metasurfaces on a transparent dielectric substrate covered by weakly absorbing analyte supporting N-H and C-H overtone absorption bands around 1.5 μ m and around 1.67 μ m, respectively. We found that the absorption enhancement in N-H overtone transition can be increased up to the factor of 22.5 due to the combination of localized surface plasmon resonance in prolonged nanoparticles and lattice Rayleigh anomaly. Our approach may be extended for sensitive identification of other functional group overtone transitions in the near-infrared spectral range.

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Lee, Umin, T. J. B. Collins, H. M. Van Horn, and R. I. Epstein. "Effects of Superfluidity on Spheroidal Oscillations of Neutron Stars." International Astronomical Union Colloquium 147 (1994): 586–90. http://dx.doi.org/10.1017/s0252921100026658.

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AbstractIn the limit of short wavelengths, it has been shown that superfluidity significantly affects wave propagation in neutron stars. Here we abandon the short-wavelength restriction and extend these calculations to global oscillation modes. In the present analysis, the solid crust of the neutron star is divided into an outer crust and an inner crust, and a superfluid of neutrons coexists with the solid lattice in the inner crust. We have computed several low-order global spheroidal modes for l = 2 both with and without superfluidity. We find that superfluidity in the inner crust affects the frequency spectra of acoustic (p-) modes, shear (s-) modes, and interfacial (i-) modes, although the surface gravity (g-) modes are not affected at all.

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Ondič, Lukáš, Marian Varga, Ivan Pelant, Alexander Kromka, Karel Hruška, and Robert G. Elliman. "Two-dimensional photonic crystals increasing vertical light emission from Si nanocrystal-rich thin layers." Beilstein Journal of Nanotechnology 9 (August 24, 2018): 2287–96. http://dx.doi.org/10.3762/bjnano.9.213.

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We have fabricated two-dimensional photonic crystals (PhCs) on the surface of Si nanocrystal-rich SiO2 layers with the goal to maximize the photoluminescence extraction efficiency in the normal direction. The fabricated periodic structures consist of columns ordered into square and hexagonal pattern with lattice constants computed such that the red photoluminescence of Si nanocrystals (SiNCs) could couple to leaky modes of the PhCs and could be efficiently extracted to surrounding air. Samples having different lattice constants and heights of columns were investigated in order to find the configuration with the best performance. Spectral overlap of the leaky modes with the luminescence spectrum of SiNCs was verified experimentally by measuring photonic band diagrams of the leaky modes employing angle-resolved spectroscopy and also theoretically by computing the reflectance spectra. The extraction enhancement within different spatial angles was evaluated by means of micro-photoluminescence spectroscopy. More than 18-fold extraction enhancement was achieved for light propagating in the normal direction and up to 22% increase in overall intensity was obtained at the spatial collection angle of 14°.

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Fradkin, Ilia M., Andrey A. Demenev, Vladimir D. Kulakovskii, Vladimir N. Antonov, and Nikolay A. Gippius. "Plasmonic grating for circularly polarized outcoupling of waveguide-enhanced spontaneous emission." Applied Physics Letters 120, no. 17 (April 25, 2022): 171702. http://dx.doi.org/10.1063/5.0085786.

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Plasmonic metasurfaces form a convenient platform for light manipulation at the nanoscale due to their specific localized surface plasmons. Even despite high intrinsic Joule losses, plasmonic nanoparticles are very effective for light manipulation. Here, we show the lattice of plasmonic nanoparticles onto a dielectric waveguide that efficiently couples oppositely propagating guided modes to circularly polarized light beams of different handedness. We demonstrate 80% degree of circular polarization for the out-coupled emission of GaAs-waveguide-embedded quantum dots. The results allow us to consider the lattice as a circular-polarization-controlled grating coupler and make this structure prospective for further implementation as an efficient coupling interface for integrated devices.

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Fradkin, Ilia M., Andrey A. Demenev, Vladimir D. Kulakovskii, Vladimir N. Antonov, and Nikolay A. Gippius. "Plasmonic grating for circularly polarized outcoupling of waveguide-enhanced spontaneous emission." Applied Physics Letters 120, no. 17 (April 25, 2022): 171702. http://dx.doi.org/10.1063/5.0085786.

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Plasmonic metasurfaces form a convenient platform for light manipulation at the nanoscale due to their specific localized surface plasmons. Even despite high intrinsic Joule losses, plasmonic nanoparticles are very effective for light manipulation. Here, we show the lattice of plasmonic nanoparticles onto a dielectric waveguide that efficiently couples oppositely propagating guided modes to circularly polarized light beams of different handedness. We demonstrate 80% degree of circular polarization for the out-coupled emission of GaAs-waveguide-embedded quantum dots. The results allow us to consider the lattice as a circular-polarization-controlled grating coupler and make this structure prospective for further implementation as an efficient coupling interface for integrated devices.

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Suresh Kumar, V., and J. Kumar. "Growth, Surface Morphology and Optical Properties of Gallium Nitride Nanowires." Advanced Materials Research 31 (November 2007): 42–52. http://dx.doi.org/10.4028/www.scientific.net/amr.31.42.

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We report on the growth mechanism, structural and optical characterstics of Gallium nitride nanowires prepared on sapphire substrates (0001) by reacting metal gallium with Gallium nitride powder and ammonia in the temperature range of 800 to 1050°C. GaN nanowires samples were characterized by using X-ray diffraction technique which shows wurtzite structure of GaN nanowires and the lattice parameters are calculated. Scanning electron microscopy images reveals that the dimension of the nanowires are around 60 – 80 nm and the length of 1 - 2 millimeters. Three Raman modes of GaN have been observed at frequencies 530, 554 and 564 cm-1. Photoluminescence spectrum reveals the band edge at 3.4 eV and gives yellow luminescence.

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Journal articles on the topic 'Surface lattice modes'

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