Articles de revues : « Phonon angular momentum »

1

Yu Hang, Xu Xi-Fang, Niu Qian et Zhang Li-Fa. « Phonon angular momentum and chiral phonons ». Acta Physica Sinica 67, n^o 7 (2018) : 076302. http://dx.doi.org/10.7498/aps.67.20172407.

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Zhu, Zhihan, Wei Gao, Chunyuan Mu et Hongwei Li. « Reversible orbital angular momentum photon–phonon conversion ». Optica 3, n^o 2 (19 février 2016) : 212. http://dx.doi.org/10.1364/optica.3.000212.

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Park, Sungjoon, et Bohm-Jung Yang. « Phonon Angular Momentum Hall Effect ». Nano Letters 20, n^o 10 (21 septembre 2020) : 7694–99. http://dx.doi.org/10.1021/acs.nanolett.0c03220.

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Krstovska, Danica, Eun Sang Choi et Eden Steven. « Giant Angular Nernst Effect in the Organic Metal α-(BEDT-TTF)2KHg(SCN)4 ». Magnetochemistry 9, n^o 1 (10 janvier 2023) : 27. http://dx.doi.org/10.3390/magnetochemistry9010027.

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We have detected a large Nernst effect in the charge density wave state of the multiband organic metal α-(BEDT-TTF)2KHg(SCN)4. We find that apart from the phonon drag effect, the energy relaxation processes that govern the electron–phonon interactions and the momentum relaxation processes that determine the mobility of the q1D charge carriers have a significant role in observing the large Nernst signal in the CDW state in this organic metal. The emphasised momentum relaxation dynamics in the low field CDW state (CDW0) is a clear indicator of the presence of a significant carrier mobility that might be the main source for observation of the largest Nernst signal. The momentum relaxation is absent with increasing angle and magnetic field, i.e., in the high-field CDW state (CDWx) as evident from the much smaller Nernst effect amplitude in this state. In this case, only the phonon drag effect and electron–phonon interactions are contributing to the transverse thermoelectric signal. Our findings advance and change previous observations on the complex properties of this organic metal.

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Todorov, Tchavdar N., Daniel Dundas, Anthony T. Paxton et Andrew P. Horsfield. « Nonconservative current-induced forces : A physical interpretation ». Beilstein Journal of Nanotechnology 2 (27 octobre 2011) : 727–33. http://dx.doi.org/10.3762/bjnano.2.79.

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We give a physical interpretation of the recently demonstrated nonconservative nature of interatomic forces in current-carrying nanostructures. We start from the analytical expression for the curl of these forces, and evaluate it for a point defect in a current-carrying system. We obtain a general definition of the capacity of electrical current flow to exert a nonconservative force, and thus do net work around closed paths, by a formal noninvasive test procedure. Second, we show that the gain in atomic kinetic energy over time, generated by nonconservative current-induced forces, is equivalent to the uncompensated stimulated emission of directional phonons. This connection with electron–phonon interactions quantifies explicitly the intuitive notion that nonconservative forces work by angular momentum transfer.

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Leckron, Kai, Alexander Baral et Hans Christian Schneider. « Exchange scattering on ultrafast timescales in a ferromagnetic two-sublattice system ». Applied Physics Letters 120, n^o 10 (7 mars 2022) : 102407. http://dx.doi.org/10.1063/5.0080379.

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We investigate ultrafast spin dynamics due to exchange, electron–phonon and Elliott–Yafet spin-flip scattering in a model with a simple band structure and ferromagnetically coupled electronic sublattices (or more generally, subsystems). We show that this incoherent model of electronic dynamics leads to sublattice magnetization changes in opposite directions after ultrashort-pulse excitation. This prominent feature on an ultrafast timescale is related to a transfer of energy and angular momentum between the subsystems due to exchange scattering. Our calculations illustrate a possible incoherent mechanism that works in addition to the coherent optically induced spin transfer mechanism.

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KOTA, V. K. B. « EIKONAL SCATTERING IN THE sdg INTERACTING BOSON MODEL : ANALYTICAL RESULTS IN THE SUsdg(3) LIMIT AND THEIR GENERALIZATIONS ». Modern Physics Letters A 08, n^o 11 (10 avril 1993) : 987–96. http://dx.doi.org/10.1142/s0217732393002464.

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General expression for the representation matrix elements in the SU sdg(3) limit of the sdg interacting boson model (sdgIBM) is derived that determine the scattering amplitude in the eikonal approximation for medium energy proton-nucleus scattering when the target nucleus is deformed and it is described by the SU sdg(3) limit. The SU sdg(3) result is generalized to two important situations: (i) when the target nucleus ground band states are described as states arising out of angular momentum projection from a general single Kπ = 0+ intrinsic state in sdg space; (ii) for rotational bands built on one-phonon excitations in sdgIBM.

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Chen, Zhanghui, et Lin-Wang Wang. « Role of initial magnetic disorder : A time-dependent ab initio study of ultrafast demagnetization mechanisms ». Science Advances 5, n^o 6 (juin 2019) : eaau8000. http://dx.doi.org/10.1126/sciadv.aau8000.

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Despite more than 20 years of development, the underlying physics of the laser-induced demagnetization process is still debated. We present a fast, real-time time-dependent density functional theory (rt-TDDFT) algorithm together with the phenomenological atomic Landau-Lifshitz-Gilbert model to investigate this problem. Our Hamiltonian considers noncollinear magnetic moment, spin-orbit coupling (SOC), electron-electron, electron-phonon, and electron-light interactions. The algorithm for time evolution achieves hundreds of times of speedup enabling calculation of large systems. Our simulations yield a demagnetization rate similar to experiments. We found that (i) the angular momentum flow from light to the system is not essential and the spin Zeeman effect is negligible. (ii) The phonon can play a role but is not essential. (iii) The initial spin disorder and the self-consistent update of the electron-electron interaction play dominant roles and enhance the demagnetization to the experimentally observed rate. The spin disorder connects the electronic structure theory with the phenomenological three-temperature model.

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Chen, Zhanghui, Jun-Wei Luo et Lin-Wang Wang. « Revealing angular momentum transfer channels and timescales in the ultrafast demagnetization process of ferromagnetic semiconductors ». Proceedings of the National Academy of Sciences 116, n^o 39 (9 septembre 2019) : 19258–63. http://dx.doi.org/10.1073/pnas.1907246116.

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Ultrafast control of magnetic order by light provides a promising realization for spintronic devices beyond Moore’s Law and has stimulated intense research interest in recent years. Yet, despite 2 decades of debates, the key question of how the spin angular momentum flows on the femtosecond timescale remains open. The lack of direct first-principle methods and pictures for such process exacerbates the issue. Here, we unravel the laser-induced demagnetization mechanism of ferromagnetic semiconductor GaMnAs, using an efficient time-dependent density functional theory approach that enables the direct real-time snapshot of the demagnetization process. Our results show a clear spin-transfer trajectory from the localized Mn-d electrons to itinerant carriers within 20 fs, illustrating the dominant role of sp−d interaction. We find that the total spin of localized electrons and itinerant carriers is not conserved in the presence of spin-orbit coupling (SOC). Immediately after laser excitation, a growing percentage of spin-angular momentum is quickly transferred to the electron orbital via SOC in about 1 ps, then slowly to the lattice via electron–phonon coupling in a few picoseconds, responsible for the 2-stage process observed experimentally. The spin-relaxation time via SOC is about 300 fs for itinerant carriers and about 700 fs for Mn-d electrons. These results provide a quantum-mechanical microscopic picture for the long-standing questions regarding the channels and timescales of spin transfer, as well as the roles of different interactions underlying the GaMnAs demagnetization process.

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Miedema, P. S., M. Beye, R. Könnecke, G. Schiwietz et A. Föhlisch. « The angular- and crystal-momentum transfer through electron–phonon coupling in silicon and silicon-carbide : similarities and differences ». New Journal of Physics 16, n^o 9 (30 septembre 2014) : 093056. http://dx.doi.org/10.1088/1367-2630/16/9/093056.

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Yamani, Z., W. J. L. Buyers, R. A. Cowley et D. Prabhakaran. « Magnetic excitations of spin and orbital moments in cobalt oxideSpecial issue on Neutron Scattering in Canada. » Canadian Journal of Physics 88, n^o 10 (octobre 2010) : 729–33. http://dx.doi.org/10.1139/p10-021.

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Magnetic and phonon excitations in the antiferromagnet CoO with an unquenched orbital angular momentum are studied by neutron scattering. Results of energy scans in several Brillouin zones in the (HHL) plane for energy transfers up to 16 THz are presented. The measurements were performed in the antiferromagnetic ordered state at 6 K (well below TN ∼290 K) as well as in the paramagnetic state at 450 K. Several magnetic excitation modes are identified from the dependence of their intensity on wavevector and temperature. Within a Hund’s rule model, the excitations correspond to fluctuations of coupled orbital and spin degrees of freedom, whose bandwidth is controlled by interionic superexchange. The different <111> ordering domains give rise to several magnetic peaks at each wavevector transfer.

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Fähnle, Manfred, Theodoros Tsatsoulis, Christian Illg, Michael Haag, Benedikt Y. Müller et Lifa Zhang. « Ultrafast Demagnetization After Femtosecond Laser Pulses : Transfer of Angular Momentum from the Electronic System to Magnetoelastic Spin-Phonon Modes ». Journal of Superconductivity and Novel Magnetism 30, n^o 5 (23 janvier 2017) : 1381–87. http://dx.doi.org/10.1007/s10948-016-3950-z.

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Celora, T., V. Khomenko, M. Antonelli et B. Haskell. « The effect of non-linear mutual friction on pulsar glitch sizes and rise times ». Monthly Notices of the Royal Astronomical Society 496, n^o 4 (6 juillet 2020) : 5564–74. http://dx.doi.org/10.1093/mnras/staa1930.

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ABSTRACT Observations of pulsar glitches have the potential to provide constraints on the dynamics of the high density interior of neutron stars. However, to do so, realistic glitch models must be constructed and compared to the data. We take a step towards this goal by testing non-linear models for the mutual friction force, which is responsible for the exchange of angular momentum between the neutron superfluid and the observable normal component in a glitch. In particular, we consider a non-linear dependence of the drag force on the relative velocity between superfluid vortices and the normal component, in which the contributions of both kelvin and phonon excitations are included. This non-linear model produces qualitatively new features, and is able to reproduce the observed bimodal distribution of glitch sizes in the pulsar population. The model also suggests that the differences in size distributions in individual pulsars may be due to the glitches being triggered in regions with different pinning strengths, as stronger pinning leads to higher vortex velocities and a qualitatively different mutual friction coupling with respect to the weak pinning case. Glitches in pulsars that appear to glitch quasi-periodically with similar sizes may thus be due to the same mechanisms as smaller events in pulsars that have no preferred glitch size, but simply originate in stronger pinning regions, possibly in the core of the star.

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Qian Wenri, 钱文日, et 张永梅 Zhang Yongmei. « 利用超表面探测光子轨道角动量的研究进展 ». Laser & ; Optoelectronics Progress 59, n^o 23 (2022) : 2300004. http://dx.doi.org/10.3788/lop202259.2300004.

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Sahoo, Pathik, Pushpendra Singh, Jhimli Manna, Ravindra P. Singh, Jonathan P. Hill, Tomonobu Nakayama, Subrata Ghosh et Anirban Bandyopadhyay. « A Third Angular Momentum of Photons ». Symmetry 15, n^o 1 (5 janvier 2023) : 158. http://dx.doi.org/10.3390/sym15010158.

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Photons that acquire orbital angular momentum move in a helical path and are observed as a light ring. During helical motion, if a force is applied perpendicular to the direction of motion, an additional radial angular momentum is introduced, and alternate dark spots appear on the light ring. Here, a third, centrifugal angular momentum has been added by twisting the helical path further according to the three-step hierarchical assembly of helical organic nanowires. Attaining a third angular momentum is the theoretical limit for a photon. The additional angular momentum converts the dimensionless photon to a hollow spherical photon condensate with interactive dark regions. A stream of these photon condensates can interfere like a wave or disintegrate like matter, similar to the behavior of electrons.

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Ayub, M. K., S. Ali et J. T. Mendonca. « Phonons with orbital angular momentum ». Physics of Plasmas 18, n^o 10 (octobre 2011) : 102117. http://dx.doi.org/10.1063/1.3655429.

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Harwit, Martin. « Photon Orbital Angular Momentum in Astrophysics ». Astrophysical Journal 597, n^o 2 (10 novembre 2003) : 1266–70. http://dx.doi.org/10.1086/378623.

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Elias, N. M. « Photon orbital angular momentum in astronomy ». Astronomy & ; Astrophysics 492, n^o 3 (15 octobre 2008) : 883–922. http://dx.doi.org/10.1051/0004-6361:200809791.

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He, Li, Huan Li et Mo Li. « Optomechanical measurement of photon spin angular momentum and optical torque in integrated photonic devices ». Science Advances 2, n^o 9 (septembre 2016) : e1600485. http://dx.doi.org/10.1126/sciadv.1600485.

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Photons carry linear momentum and spin angular momentum when circularly or elliptically polarized. During light-matter interaction, transfer of linear momentum leads to optical forces, whereas transfer of angular momentum induces optical torque. Optical forces including radiation pressure and gradient forces have long been used in optical tweezers and laser cooling. In nanophotonic devices, optical forces can be significantly enhanced, leading to unprecedented optomechanical effects in both classical and quantum regimes. In contrast, to date, the angular momentum of light and the optical torque effect have only been used in optical tweezers but remain unexplored in integrated photonics. We demonstrate the measurement of the spin angular momentum of photons propagating in a birefringent waveguide and the use of optical torque to actuate rotational motion of an optomechanical device. We show that the sign and magnitude of the optical torque are determined by the photon polarization states that are synthesized on the chip. Our study reveals the mechanical effect of photon’s polarization degree of freedom and demonstrates its control in integrated photonic devices. Exploiting optical torque and optomechanical interaction with photon angular momentum can lead to torsional cavity optomechanics and optomechanical photon spin-orbit coupling, as well as applications such as optomechanical gyroscopes and torsional magnetometry.

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Liu, Houquan, Zhenghao Xie, Jiankang Xu et Libo Yuan. « On-Chip Photon Angular Momentum Absolute Measurement Based on Angle Detection ». Nanomaterials 12, n^o 5 (2 mars 2022) : 847. http://dx.doi.org/10.3390/nano12050847.

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Photon angular momentum (AM) has been widely studied due to its unique properties. The accurate detection of photon AM is very important in its wide applications. Though various on-chip AM detectors based on surface plasmon polaritons (SPPs) have been proposed, most of them can only realize relative measurement. For example, most photon orbital angular momentum (OAM) detectors measure the high order OAM via measuring the relative interval between the intensity spots of the SPPs excited by the target order OAM beam and the reference order (usually 0th order) OAM beam. In this paper, we propose a simple on-chip photon AM detector. It can realize absolute measurement of photon OAM via angle detection, whose measurement result does not depend on the measurement of any reference OAM beam. At the same time, it can also recognize photon spin angular momentum (SAM). The proposed detector provides a new way for absolute measurement of photon AM, which may have some potential applications in the field of integrated photonic device.

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Chen, Dong-Xu, Pei Zhang, Rui-Feng Liu, Hong-Rong Li, Hong Gao et Fu-Li Li. « Orbital angular momentum filter of photon based on spin-orbital angular momentum coupling ». Physics Letters A 379, n^o 39 (octobre 2015) : 2530–34. http://dx.doi.org/10.1016/j.physleta.2015.06.022.

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Chi, Cheng, Qiao Jiang, Zhixin Liu, Liheng Zheng, Meiling Jiang, Han Zhang, Feng Lin, Bo Shen et Zheyu Fang. « Selectively steering photon spin angular momentum via electron-induced optical spin Hall effect ». Science Advances 7, n^o 18 (avril 2021) : eabf8011. http://dx.doi.org/10.1126/sciadv.abf8011.

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The development of the optical spin Hall effect (OSHE) realizes the splitting of different spin components, contributing to the manipulation of photon spin angular momentum that acts as the information carrier for quantum technology. However, OSHE with optical excitation lacks active control of photon angular momentum at deep subwavelength scale because of the optical diffraction limit. Here, we experimentally demonstrate a selective manipulation of photon spin angular momentum at a deep subwavelength scale via electron-induced OSHE in Au nanoantennas. The inversion of the OSHE radiation pattern is observed by angle-resolved cathodoluminescence polarimetry with the electron impact position shifting within 80 nm in a single antenna unit. By this selective steering of photon spin, we propose an information encoding with robustness, privacy, and high level of integration at a deep subwavelength scale for the future quantum applications.

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Ballantine, Kyle E., John F. Donegan et Paul R. Eastham. « There are many ways to spin a photon : Half-quantization of a total optical angular momentum ». Science Advances 2, n^o 4 (avril 2016) : e1501748. http://dx.doi.org/10.1126/sciadv.1501748.

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The angular momentum of light plays an important role in many areas, from optical trapping to quantum information. In the usual three-dimensional setting, the angular momentum quantum numbers of the photon are integers, in units of the Planck constantħ. We show that, in reduced dimensions, photons can have a half-integer total angular momentum. We identify a new form of total angular momentum, carried by beams of light, comprising an unequal mixture of spin and orbital contributions. We demonstrate the half-integer quantization of this total angular momentum using noise measurements. We conclude that for light, as is known for electrons, reduced dimensionality allows new forms of quantization.

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Liu, Rui-Xi, et Lei Ma. « Effects of ocean turbulence on photon orbital angular momentum quantum communication ». Acta Physica Sinica 71, n^o 1 (2022) : 010304. http://dx.doi.org/10.7498/aps.71.20211146.

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The effect of the turbulent motion of ocean on the quantum communication based on the orbital angular momentum in an underwater quantum channel is studied in this work. Based on the power spectrum model of ocean turbulence proposed by Elamassie, the quantitative relationships of different ocean turbulence parameters with the single photon detection probability of orbital angular momentum photons, the channel capacity, the key generation rate, the concurrence of two entangled photons are proposed. The maximum entanglement distance of the orbital angular momentum entangled photon-pairs in the ocean turbulence is further studied by the universal entanglement decay of the concurrence of entangled photon-pairs in the ocean turbulence. The results show that the detection probability of single photon, the channel capacity, the key generation rate, and the concurrence of entangled photon-pairs decrease with the increase of the dissipation rate of turbulent kinetic energy and the decrease of the rate of dissipation of mean-squared temperature. The influence of the temperature and salinity balance parameter of ocean turbulence on the performance of underwater quantum communication are significantly different under the condition of whether the stable stratification of seawater is assumed or not. In the ocean turbulent environment, the increasing of the initial orbital angular momentum quantum number of signal photons can improve the key generation rate of quantum key distribution and the resistance of entangled photons to entanglement decay.

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Santamato, E. « Photon orbital angular momentum : problems and perspectives ». Fortschritte der Physik 52, n^o 11-12 (1 novembre 2004) : 1141–53. http://dx.doi.org/10.1002/prop.200410184.

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KIM, Teun-Teun. « Spin-Orbital Angular Momentum of Light and Its Application ». Physics and High Technology 29, n^o 10 (31 octobre 2020) : 28–31. http://dx.doi.org/10.3938/phit.29.037.

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Like the eletron, the photon carries spin and orbital angular momentum caused by the polarization and the spatial phase distribution of light, respectively. Since the first observation of an optical vortex beam with orbital angular momentum (OAM), the use of an optical vortex beam has led to further studies on the light-matter interaction, the quantum nature of light, and a number of applications. In this article, using a metasurface with geometrical phase, we introduce the fundamental origins and some important applications of light with spin-orbit angular momentum as examples, including optical vortex tweezer and quantum entanglement of the spin-orbital angular momentum.

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Kotlyar, V. V., A. A. Kovalev et A. P. Porfirev. « Measurement of the orbital angular momentum of an astigmatic Hermite–Gaussian beam ». Computer Optics 43, n^o 3 (juin 2019) : 356–67. http://dx.doi.org/10.18287/2412-6179-2019-43-3-356-367.

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Here we study three different types of astigmatic Gaussian beams, whose complex amplitude in the Fresnel diffraction zone is described by the complex argument Hermite polynomial of the order (n, 0). The first type is a circularly symmetric Gaussian optical vortex with and a topological charge n after passing through a cylindrical lens. On propagation, the optical vortex "splits" into n first-order optical vortices. Its orbital angular momentum per photon is equal to n. The second type is an elliptical Gaussian optical vortex with a topological charge n after passing through a cylindrical lens. With a special choice of the ellipticity degree (1: 3), such a beam retains its structure upon propagation and the degenerate intensity null on the optical axis does not “split” into n optical vortices. Such a beam has fractional orbital angular momentum not equal to n. The third type is the astigmatic Hermite-Gaussian beam (HG) of order (n, 0), which is generated when a HG beam passes through a cylindrical lens. The cylindrical lens brings the orbital angular momentum into the original HG beam. The orbital angular momentum of such a beam is the sum of the vortex and astigmatic components, and can reach large values (tens and hundreds of thousands per photon). Under certain conditions, the zero intensity lines of the HG beam "merge" into an n-fold degenerate intensity null on the optical axis, and the orbital angular momentum of such a beam is equal to n. Using intensity distributions of the astigmatic HG beam in foci of two cylindrical lenses, we calculate the normalized orbital angular momentum which differs only by 7 % from its theoretical orbital angular momentum value (experimental orbital angular momentum is –13,62, theoretical OAM is –14.76).

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Gordon, D. F., B. Hafizi et A. Ting. « Nonlinear conversion of photon spin to photon orbital angular momentum ». Optics Letters 34, n^o 21 (22 octobre 2009) : 3280. http://dx.doi.org/10.1364/ol.34.003280.

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Tauchert, S. R., M. Volkov, D. Ehberger, D. Kazenwadel, M. Evers, H. Lange, A. Donges et al. « Polarized phonons carry angular momentum in ultrafast demagnetization ». Nature 602, n^o 7895 (2 février 2022) : 73–77. http://dx.doi.org/10.1038/s41586-021-04306-4.

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Keller, Ole, et Gang Wang. « Angular momentum photon drag in a mesoscopic ring ». Optics Communications 138, n^o 1-3 (mai 1997) : 75–80. http://dx.doi.org/10.1016/s0030-4018(97)00018-7.

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LEHNERT, BO. « On angular momentum and rest mass of the photon ». Journal of Plasma Physics 79, n^o 6 (décembre 2013) : 1133–35. http://dx.doi.org/10.1017/s002237781300069x.

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AbstractA reconsideration is made on the basic concepts of the individual photon, including its angular momentum (spin) and a possibly existing very small rest mass. In terms of conventional classical theory, as well as of its quantum mechanical counterpart, the results from a so far established Standard Model of an empty vacuum state are not found to be reconcilable with an experimentally relevant photon model. The main properties of such a model would on the other hand become compatible with the results of a recently established revised quantum electrodynamic theory based on a non-zero electric field divergence in the vacuum and a corresponding symmetry breaking of the electromagnetic field.

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BINI, DONATO, et ANDREA GERALICO. « EQUILIBRIUM ORBITS OF PARTICLES UNDERGOING POYNTING-ROBERTSON EFFECT IN SCHWARZSCHILD SPACETIME ». International Journal of Modern Physics : Conference Series 12 (janvier 2012) : 247–55. http://dx.doi.org/10.1142/s2010194512006447.

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Equilibrium orbits of particles moving on the equatorial plane of a Schwarzschild spacetime are investigated when a test radiation field is superposed to the background gravitational field. The radiation flux is endowed with a fixed but arbitrary (non-zero) angular momentum. It is found that multiple equilibrium circular orbit exist provided that the photon angular momentum is sufficiently high. The stability of such orbits is also analyzed.

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Hofbrucker, Jiri, Latifeh Eiri, Andrey V. Volotka et Stephan Fritzsche. « Photoelectron Angular Distributions of Nonresonant Two-Photon Atomic Ionization Near Nonlinear Cooper Minima ». Atoms 8, n^o 3 (3 septembre 2020) : 54. http://dx.doi.org/10.3390/atoms8030054.

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Photoelectron angular distributions of the two-photon ionization of neutral atoms are theoretically investigated. Numerical calculations of two-photon ionization cross sections and asymmetry parameters are carried out within the independent-particle approximation and relativistic second-order perturbation theory. The dependence of the asymmetry parameters on the polarization and energy of the incident light as well as on the angular momentum properties of the ionized electron are investigated. While dynamic variations of the angular distributions at photon energies near intermediate level resonances are expected, we demonstrate that equally strong variations occur near the nonlinear Cooper minimum. The described phenomena is demonstrated on the example of two-photon ionization of magnesium atom.

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Leader, Elliot. « A proposed measurement of optical orbital and spin angular momentum and its implications for photon angular momentum ». Physics Letters B 779 (avril 2018) : 385–87. http://dx.doi.org/10.1016/j.physletb.2018.02.029.

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Fickler, Robert, Geoff Campbell, Ben Buchler, Ping Koy Lam et Anton Zeilinger. « Quantum entanglement of angular momentum states with quantum numbers up to 10,010 ». Proceedings of the National Academy of Sciences 113, n^o 48 (15 novembre 2016) : 13642–47. http://dx.doi.org/10.1073/pnas.1616889113.

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Photons with a twisted phase front carry a quantized amount of orbital angular momentum (OAM) and have become important in various fields of optics, such as quantum and classical information science or optical tweezers. Because no upper limit on the OAM content per photon is known, they are also interesting systems to experimentally challenge quantum mechanical prediction for high quantum numbers. Here, we take advantage of a recently developed technique to imprint unprecedented high values of OAM, namely spiral phase mirrors, to generate photons with more than 10,000 quanta of OAM. Moreover, we demonstrate quantum entanglement between these large OAM quanta of one photon and the polarization of its partner photon. To our knowledge, this corresponds to entanglement with the largest quantum number that has been demonstrated in an experiment. The results may also open novel ways to couple single photons to massive objects, enhance angular resolution, and highlight OAM as a promising way to increase the information capacity of a single photon.

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Grinter, Roger. « Photon angular momentum : selection rules and multipolar transition moments ». Journal of Physics B : Atomic, Molecular and Optical Physics 41, n^o 9 (22 avril 2008) : 095001. http://dx.doi.org/10.1088/0953-4075/41/9/095001.

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Kristensen, M., et J. P. Woerdman. « Is photon angular momentum conserved in a dielectric medium ? » Physical Review Letters 72, n^o 14 (4 avril 1994) : 2171–74. http://dx.doi.org/10.1103/physrevlett.72.2171.

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Turaykhanov, D. A., D. O. Akat’ev, A. V. Shkalikov, V. S. Romanov et A. A. Kalachev. « Heralded single-photon states generated via spontaneous parametric down-conversion with an orbital angular momentum controlled by the pump field ». EPJ Web of Conferences 220 (2019) : 02018. http://dx.doi.org/10.1051/epjconf/201922002018.

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AFANASEV, ANDREI, CARL E. CARLSON et ASMITA MUKHERJEE. « ORBITAL ANGULAR MOMENTUM OF GAUGE FIELDS : EXCITATION OF AN ATOM BY TWISTED PHOTONS ». International Journal of Modern Physics : Conference Series 25 (janvier 2014) : 1460048. http://dx.doi.org/10.1142/s2010194514600489.

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Twisted photon states, or photon states with large (> ℏ) angular momentum projection in the direction of motion, can photoexcite atomic final states of differing quantum numbers. If the photon symmetry axis coincides with the center of an atom, there are known selection rules that require exact matching between the quantum numbers of the photon and the photoexcited states. The more general case of arbitrarily positioned beams relaxes the selection rules but produces a distribution of quantum numbers of the final atomic states that is novel and distinct from final states produced by plane-wave photons. Numerical calculations are presented using a hydrogen atom as an example.

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Yu, Qian, Chuan Xu, Sixin Chen, Pengcheng Chen, Saiwei Nie, Shijie Ke, Dunzhao Wei, Min Xiao et Yong Zhang. « Manipulating Orbital Angular Momentum Entanglement in Three-Dimensional Spiral Nonlinear Photonic Crystals ». Photonics 9, n^o 7 (21 juillet 2022) : 504. http://dx.doi.org/10.3390/photonics9070504.

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We propose and theoretically investigate two-photon orbital angular momentum (OAM) correlation through spontaneous parameter down-conversion (SPDC) processes in three-dimensional (3D) spiral nonlinear photonic crystals (NPCs). By properly designing the NPC structure, one can feasibly modulate the OAM-correlated photon pair, which provides a potential platform to realize high-dimensional entanglement for quantum information processing and quantum communications.

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Pecoraro, Adriana, Filippo Cardano, Lorenzo Marrucci et Alberto Porzio. « Continuous Variable Entanglement in Non-Zero Orbital Angular Momentum States ». Proceedings 12, n^o 1 (11 octobre 2019) : 7. http://dx.doi.org/10.3390/proceedings2019012007.

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Orbital angular momentum is a discrete degree of freedom that can access an infinite dimensional Hilbert space, thus enhancing the information capacity of a single optical beam. Continuous variables field quadratures allow achieving some quantum tasks in a more advantageous way with respect to the use of photon-number states. Here, we use a hybrid approach realizing bipartite continuous-variable Gaussian entangled state made up of two electromagnetic modes carrying orbital angular momentum. A q-plate is used for endowing a pair of entangled beams with such a degree of freedom. This quantum state is then completely characterized thanks to a novel design of a homodyne detector in which also the local oscillator is an orbital angular momentum-carrying beams so allowing the direct detection of vortex modes quadratures.

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Wang, Yuanxiang, ShuZhen Li, Youyou Hu, Mingming Zhang et Jun Liu. « Improvement of angular rotation measurement resolution and sensitivity based on an SU(1,1) interferometer with intensity sum detection ». Journal of Physics Communications 6, n^o 3 (1 mars 2022) : 035004. http://dx.doi.org/10.1088/2399-6528/ac5da9.

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Abstract In order to realize the enhancement of angular rotation measurement sensitivity, a new scheme based on an SU(1,1) interferometer with intensity sum detection has been proposed. A coherent beam carrying orbital angular momentum (OAM) enters into the SU(1,1) interferometer where the Dove prisms are inserted. By taking full advantage of the two outports and employing intensity sum detection, the angular rotation measurement sensitivity can be enhanced by higher gain, photon number and OAM. Meanwhile, resolution can be improved while the pump beam carries OAM. The angular rotation measurement sensitivity of the SU(1,1) interferometer can beat standard quantum limit 1 / ( 2 l N ), and it still can be optimal when photon depletion inside this interferometer is the same.

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Ke Xi-Zheng, Nu Ning et Yang Qin-Ling. « Research of transmission characteristics of single-photon orbital angular momentum ». Acta Physica Sinica 59, n^o 9 (2010) : 6159. http://dx.doi.org/10.7498/aps.59.6159.

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Zadernovsky, A. A. « Excitation of nuclei by photon beams carrying orbital angular momentum ». Laser Physics 16, n^o 4 (avril 2006) : 571–75. http://dx.doi.org/10.1134/s1054660x06040062.

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Jassemnejad, Baha. « Mode sorter and detector based on photon orbital angular momentum ». Optical Engineering 47, n^o 5 (1 mai 2008) : 053001. http://dx.doi.org/10.1117/1.2931686.

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Wang, Fang-Xiang, Juan Wu, Wei Chen, Zhen-Qiang Yin, Shuang Wang, Guang-Can Guo et Zheng-Fu Han. « Controlled-phase manipulation module for orbital-angular-momentum photon states ». Optics Letters 43, n^o 2 (12 janvier 2018) : 349. http://dx.doi.org/10.1364/ol.43.000349.

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Piccirillo, B., C. Toscano, F. Vetrano et E. Santamato. « Orbital and Spin Photon Angular Momentum Transfer in Liquid Crystals ». Physical Review Letters 86, n^o 11 (12 mars 2001) : 2285–88. http://dx.doi.org/10.1103/physrevlett.86.2285.

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Tamburini, F., A. Sponselli, B. Thidé et J. T. Mendonça. « Photon orbital angular momentum and mass in a plasma vortex ». EPL (Europhysics Letters) 90, n^o 4 (1 mai 2010) : 45001. http://dx.doi.org/10.1209/0295-5075/90/45001.

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Sasaki, R., Y. Nii et Y. Onose. « Magnetization control by angular momentum transfer from surface acoustic wave to ferromagnetic spin moments ». Nature Communications 12, n^o 1 (10 mai 2021). http://dx.doi.org/10.1038/s41467-021-22728-6.

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AbstractInterconversion between electron spin and other forms of angular momentum is useful for spin-based information processing. Well-studied examples of this are the conversion of photon angular momentum and rotation into ferromagnetic moment. Recently, several theoretical studies have suggested that the circular vibration of atoms work as phonon angular momentum; however, conversion between phonon angular momentum and spin-moment has yet to be demonstrated. Here, we demonstrate that the phonon angular momentum of surface acoustic wave can control the magnetization of a ferromagnetic Ni film by means of the phononic-to-electronic conversion of angular momentum in a Ni/LiNbO3 hybrid device. The result clearly shows that the phonon angular momentum is useful for increasing the functionality of spintronic devices.

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Garanin, D. A., et E. M. Chudnovsky. « Angular momentum in spin-phonon processes ». Physical Review B 92, n^o 2 (20 juillet 2015). http://dx.doi.org/10.1103/physrevb.92.024421.

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