Journal articles: 'Phase transition'

1

Tang, Xiaochu, and Yuan Li. "Phase division and transition modeling based on the dominant phase identification for multiphase batch process quality prediction." Transactions of the Institute of Measurement and Control 42, no. 5 (November 4, 2019): 1022–36. http://dx.doi.org/10.1177/0142331219881343.

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Batch processes are carried out from one steady phase to another one, which may have multiphase and transitions. Modeling in transitions besides in the steady phases should also be taken into consideration for quality prediction. In this paper, a quality prediction strategy is proposed for multiphase batch processes. First, a new repeatability factor is introduced to divide batch process into different steady phases and transitions. Then, the different local cumulative models that considered the cumulative effect of process variables on quality are established for steady phases and transitions. Compared with the reported modeling methods in transitions, a novel just-in-time model can be established based on the dominant phase identification. The proposed method can not only consider the dynamic characteristic in the transition but also improve the accuracy and the efficiency of transitional models. Finally, online quality prediction is performed by accumulating the prediction results from different phases and transitions. The effectiveness of the proposed method is demonstrated by penicillin fermentation process.

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Scott, Adam D., Dawn M. King, Stephen W. Ordway, and Sonya Bahar. "Phase transitions in evolutionary dynamics." Chaos: An Interdisciplinary Journal of Nonlinear Science 32, no. 12 (December 2022): 122101. http://dx.doi.org/10.1063/5.0124274.

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Sharp changes in state, such as transitions from survival to extinction, are hallmarks of evolutionary dynamics in biological systems. These transitions can be explored using the techniques of statistical physics and the physics of nonlinear and complex systems. For example, a survival-to-extinction transition can be characterized as a non-equilibrium phase transition to an absorbing state. Here, we review the literature on phase transitions in evolutionary dynamics. We discuss directed percolation transitions in cellular automata and evolutionary models, and models that diverge from the directed percolation universality class. We explore in detail an example of an absorbing phase transition in an agent-based model of evolutionary dynamics, including previously unpublished data demonstrating similarity to, but also divergence from, directed percolation, as well as evidence for phase transition behavior at multiple levels of the model system's evolutionary structure. We discuss phase transition models of the error catastrophe in RNA virus dynamics and phase transition models for transition from chemistry to biochemistry, i.e., the origin of life. We conclude with a review of phase transition dynamics in models of natural selection, discuss the possible role of phase transitions in unraveling fundamental unresolved questions regarding multilevel selection and the major evolutionary transitions, and assess the future outlook for phase transitions in the investigation of evolutionary dynamics.

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SOLLER, H., and D. BREYEL. "SIGNATURES IN THE CONDUCTANCE FOR PHASE TRANSITIONS IN EXCITONIC SYSTEMS." Modern Physics Letters B 27, no. 25 (September 23, 2013): 1350185. http://dx.doi.org/10.1142/s0217984913501856.

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In this paper, we analyze two phase transitions in exciton bilayer systems: a topological phase transition to a phase which hosts Majorana fermions and a phase transition to a Wigner crystal. Using generic simple models for different phases, we discuss the conductance properties of the latter when contacted to metallic leads and demonstrate the possibility to observe the different phase transitions by simple conductance measurements.

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Weidemann, Sebastian, Mark Kremer, Stefano Longhi, and Alexander Szameit. "Topological triple phase transition in non-Hermitian Floquet quasicrystals." Nature 601, no. 7893 (January 19, 2022): 354–59. http://dx.doi.org/10.1038/s41586-021-04253-0.

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AbstractPhase transitions connect different states of matter and are often concomitant with the spontaneous breaking of symmetries. An important category of phase transitions is mobility transitions, among which is the well known Anderson localization1, where increasing the randomness induces a metal–insulator transition. The introduction of topology in condensed-matter physics2–4 lead to the discovery of topological phase transitions and materials as topological insulators5. Phase transitions in the symmetry of non-Hermitian systems describe the transition to on-average conserved energy6 and new topological phases7–9. Bulk conductivity, topology and non-Hermitian symmetry breaking seemingly emerge from different physics and, thus, may appear as separable phenomena. However, in non-Hermitian quasicrystals, such transitions can be mutually interlinked by forming a triple phase transition10. Here we report the experimental observation of a triple phase transition, where changing a single parameter simultaneously gives rise to a localization (metal–insulator), a topological and parity–time symmetry-breaking (energy) phase transition. The physics is manifested in a temporally driven (Floquet) dissipative quasicrystal. We implement our ideas via photonic quantum walks in coupled optical fibre loops11. Our study highlights the intertwinement of topology, symmetry breaking and mobility phase transitions in non-Hermitian quasicrystalline synthetic matter. Our results may be applied in phase-change devices, in which the bulk and edge transport and the energy or particle exchange with the environment can be predicted and controlled.

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Hu, Xi Duo, De Hai Zhu, Zhi Feng Zeng, and Shao Rui Sun. "The Theoretical Study of the Cinnabar-to-Rocksalt Phase Transitions of HgTe and CdTe under High Pressure." Advanced Materials Research 1004-1005 (August 2014): 1608–14. http://dx.doi.org/10.4028/www.scientific.net/amr.1004-1005.1608.

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We performed the first-principle calculation to study the structures of cinnabar phase and the Cinnabar-to-rocksalt Phase transitions of HgTe and CdTe under high pressure. The calculated results show that for HgTe, the zincblende-to-cinnabar phase transition is under 2.2GPa, and the cinnabar-to-rocksalt phase transition is under 5.5 GPa; For CdTe, the two phase transitions occur under 4.0 GPa and 4.9 GPa, respectively, which well agree with the experimental results. The cinnabar-to-rocksalt phase transitions of most compounds, including HgTe and CdTe, except HgS are of first-order, and it is due to that their cinnabar phases are not chain structure as HgS and there are no relaxation process before the phase transition.

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Bauer, Michael, and Wilfrid E. Klee. "The monoclinic-hexagonal phase transition in chlorapatite." European Journal of Mineralogy 5, no. 2 (April 27, 1993): 307–16. http://dx.doi.org/10.1127/ejm/5/2/0307.

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7

Nechaev, V. N., and A. V. Shuba. "The size effects on phase transitions in ferroics." Известия Российской академии наук. Серия физическая 87, no. 9 (September 1, 2023): 1229–36. http://dx.doi.org/10.31857/s0367676523702174.

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The features of phase transitions temperature behavior in nanosized ferroics are discussed in the framework of phenomenological theories. It is shown that in the case of second-order transitions to both the commensurate and incommensurate phases, the critical temperature can shift significantly depending on the characteristic dimensions of the sample and the properties of the surface. In materials with the first-order phase transition, size effects have a significant influence on the nucleation process, leading to the transition temperature shift or even the phase transition type change have been determined.

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8

Krishnamoorthy, Aravind, Lindsay Bassman, Rajiv K. Kalia, Aiichiro Nakano, Fuyuki Shimojo, and Priya Vashishta. "Kinetics and Atomic Mechanisms of Structural Phase Transformations in Photoexcited Monolayer TMDCs." MRS Advances 3, no. 6-7 (2018): 345–50. http://dx.doi.org/10.1557/adv.2018.122.

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ABSTRACTRapid transitions between semiconducting and metallic phases of transition-metal dichalcogenides are of interest for 2D electronics applications. Theoretical investigations have been limited to using thermal energy, lattice strain and charge doping to induce the phase transition, but have not identified mechanisms for rapid phase transition. Here, we use density functional theory to show how optical excitation leads to the formation of a low-energy intermediate crystal structure along the semiconductor-metal phase transition pathway. This metastable crystal structure results in significantly reduced barriers for the semiconducting-metal phase transition pathway leading to rapid transition in optically excited crystals.

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9

Nguyen, Thi Phuong Thuy, Thi Van Anh Nguyen, and Van Thanh Ngo. "Phase transitions of smectic-isotropic phase in liquid crystals." Ministry of Science and Technology, Vietnam 66, no. 1 (January 15, 2024): 1–7. http://dx.doi.org/10.31276/vjst.66(1).01-07.

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Smectic phases formed by rod-like molecules with long axes that are parallel and also arranged in planes. The smectic-isotropic phase transition is a phase change from the liquid crystal to the liquid phase. In this work, we use a mobile 6-state Potts model to study the nature of the smectic-isotropic phase transition. Microscopic interactions between neighbouring molecules in this model are supplemented with the Lennard-Jones potential. This study applies Monte Carlo simulation with the Wang-Landau algorithm to determine the characteristics of smectic-isotropic phase transitions. It is shown clearly that the smectic phase goes to the isotropic phase and undergoes a first-order transition. The results also point out that when the temperature increases, molecules on the surface are orientationally disordered, then the molecules gradually lose their positional order. These results are in agreement with experiments that revealed the coexistence of the smectic and isotropic phasesduring the phase transition process in accordance with experimental studies.

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10

Kuryleva, Yulia N., Olga A. Chalaya, and D. A. Zakharyevich. "Phase Transitions in Perovskite Phases of Strontium Silicoantimonates." Materials Science Forum 845 (March 2016): 34–37. http://dx.doi.org/10.4028/www.scientific.net/msf.845.34.

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The paper presents the results of the study of phase transitions in the system Sr-Sb-Si-O by means of X-ray diffraction, thermal analysis, dielectric spectroscopy. Four effects are observed in the interval from room temperature to 800°C. The first and last are chemical transformations due to dehydration and loss of oxygen, respectively. The second is a transition from tetragonal to cubic perovskite structure, and the third is disordering transition in oxygen sublattice possibly due to the desorption of structural water molecules

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11

Paroli, Ralph M., Nancy T. Kawai, Ian S. Butler, and Denis F. R. Gilson. "Phase transitions in adamantane derivatives: 2-chloroadamantane." Canadian Journal of Chemistry 66, no. 8 (August 1, 1988): 1973–78. http://dx.doi.org/10.1139/v88-318.

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The phase transition behaviour of 2-chloroadamantane, 2-C10H15Cl, has been investigated by differential scanning calorimetry (DSC), and FT-IR and Raman spectroscopy. Two transitions were detected by both DSC and vibrational spectroscopy at 231 and 178 K, on cooling, and at 242 and 227 K, on heating. The measured enthalpies were 8.3 kJ mol−1 for the first transition (phase I → phase II), and 0.47 kJ mol−1 for the second (phase II → phase III). The entropies were 35 and 2.3 J K−1 mol−1, respectively. These are similar to those observed for other 2-substituted adamantanes, but significantly different from those for 1-substituted derivatives. The large hystereses observed for the two transitions are independent of the DSC scanning rate and are characteristic of first-order phase transitions. The dramatic differences observed in the vibrational spectra of phases I and II provide clear evidence of an order–disorder transition at about 235 K.

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12

Rakovan, John. "Phase Transition." Rocks & Minerals 81, no. 6 (January 2006): 467–69. http://dx.doi.org/10.3200/rmin.81.6.467-469.

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13

Rothman, Tony. "Phase Transition." Scientific American 259, no. 3 (September 1988): 30–31. http://dx.doi.org/10.1038/scientificamerican0988-30.

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14

Irfan, Sheheera, Yasir A. Haleem, Muhammad Imran Irshad, Muhammad Farooq Saleem, Muhammad Arshad, and Muhammad Habib. "Tunability of the Optical Properties of Transition-Metal-Based Structural Phase Change Materials." Optics 4, no. 2 (May 24, 2023): 351–63. http://dx.doi.org/10.3390/opt4020026.

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Phase transitions are an intriguing yet poorly understood aspect of transition-metal-based materials; these phase transitions can result in changes to the refractive index, absorption coefficient, and other optical properties of the materials. Transition-metal-based materials exist in a variety of crystalline phases and also have metallic, semi-metallic, and semi-conducting characteristics. In this review, we demonstrate that alloyed W- and Mo-based dichalcogenides enable phase transitions in structures, with phase transition temperatures that are tunable across a wide range using various alloy models and modern DFT-based calculations. We also analyze the tuning the optical bandgap of the metal oxide nanoparticles through doping of the transition metal in a manner that is suitable for optical switching and thermal imaging. After the introduction and a brief illustration of the structures and their exceptional properties, we discuss synthetic methodologies and their application as part of important strategies toward the enhanced performance of transition-metal-based dichalcogenides and oxides. In the end, our conclusion highlights the prospects of 2D materials as phase transition materials due to their advantages in terms of scalability and adaptability.

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15

Zhang, Xinyu, Lidong Dai, Haiying Hu, and Chuang Li. "Pressure-Induced Reverse Structural Transition of Calcite at Temperatures up to 873 K and Pressures up to 19.7 GPa." Minerals 13, no. 2 (January 27, 2023): 188. http://dx.doi.org/10.3390/min13020188.

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In situ Raman scattering and electrical conductivity experiments have been performed to investigate the structural phase transitions of calcite during the compressed and decompressed processes in a diamond anvil cell at temperatures of 298–873 K and pressures up to 19.7 GPa. Upon compression, calcite (CaCO3-I phase) underwent three structural phase transitions from CaCO3-I to CaCO3-II phases at 1.6 GPa, from CaCO3-II to CaCO3-III phases at 2.2 GPa, and from CaCO3-III to CaCO3-VI phases at 16.8 GPa under room temperature conditions, which were evidenced by the evolution of Raman peaks, as well as the discontinuities in the pressure-dependent Raman shifts and electrical conductivity. Upon decompression, the structural phase transitions from CaCO3-VI to CaCO3-III to CaCO3-II to CaCO3-I phases took place at the respective pressures of 5.4, 1.5, and 0.4 GPa, indicating the reversibility of calcite. Furthermore, an obvious ~11 GPa of pressure hysteresis was detected in the CaCO3-VI to CaCO3-III phase transition, whereas other reverse phase transition pressures were very close to those of compressed results. At three given representative pressure conditions (i.e., 10.5, 12.5, and 13.8 GPa), a series of electrical conductivity experiments were performed at temperature ranges of 323–873 K to explore the temperature-dependent relation of CaCO3-III to CaCO3-VI structural phase transition. With increasing pressure, the transition temperature between CaCO3-III and CaCO3-VI phases gradually decreases, which reveals an obviously negative temperature-pressure relation, i.e., P (GPa) = 19.219 (±1.105) − 0.011 (±0.002) T (K). Our acquired phase diagram of calcite can be employed to understand the high-pressure structural transitions and phase stability for carbonate minerals along various subducting slabs in the deep Earth’s interior.

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16

KIM, SANG PYO. "DYNAMICAL THEORY OF PHASE TRANSITIONS AND COSMOLOGICAL EW AND QCD PHASE TRANSITIONS." Modern Physics Letters A 23, no. 17n20 (June 28, 2008): 1325–35. http://dx.doi.org/10.1142/s0217732308027692.

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We critically review the cosmological EW and QCD phase transitions. The EW and QCD phase transitions would have proceeded dynamically since the expansion of the universe determines the quench rate and critical behaviors at the onset of phase transition slow down the phase transition. We introduce a real-time quench model for dynamical phase transitions and describe the evolution using a canonical real-time formalism. We find the correlation function, the correlation length and time and then discuss the cosmological implications of dynamical phase transitions on EW and QCD phase transitions in the early universe.

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17

Comodi, Paola, Francesco Guidoni, Sabrina Nazzareni, Tonci Balić-Žunić, Azzurra Zucchini, Emil Makovicky, and Vitali Prakapenka. "A high-pressure phase transition in chalcostibite, CuSbS2." European Journal of Mineralogy 30, no. 3 (September 1, 2018): 491–505. http://dx.doi.org/10.1127/ejm/2018/0030-2728.

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18

Yurov, V. M., S. A. Guchenko, V. Ch Laurinas, and O. N. Zavatskaya. "Structural phase transition in surface layer of metals." Bulletin of the Karaganda University. "Physics" Series 93, no. 1 (March 29, 2019): 50–60. http://dx.doi.org/10.31489/2019ph1/50-60.

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19

Suhara, Masahiko, and Koichi Mano. "NQR and Phase Transitions in Hexachlorocyclopropane Crystal." Zeitschrift für Naturforschung A 45, no. 3-4 (April 1, 1990): 339–42. http://dx.doi.org/10.1515/zna-1990-3-421.

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Abstract35Cl NQR and DSC studies on phase transitions in hexachlorocyclopropane (HCCP), C3Cl6 , are reported. It is found that HCCP has three solid phases: A high temperature disordered phase (Phase I) above 301 K (no NQR spectrum was observed); a metastable phase (Phase II), which exhibited 6 NQR lines from 77 to 270 K; a low temperature phase (Phase III) in which a 24-multiplet of 35Cl NQR lines at 77 K, the most complex multiplet spectrum ever reported was observed. DSC measurement shows a A-type transition at 301 K and a broad transition of very slow rate at 285 K. The structure and mechanism of phase transitions in HCCP crystal are discussed.

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Babaev A. B. and Murtazaev A. K. "The effect of nonmagnetic disorder on phase transitions of the first-order." Physics of the Solid State 65, no. 4 (2023): 619. http://dx.doi.org/10.21883/pss.2023.04.56004.407.

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Using the Monte Carlo method, weakly dilute magnetic systems described by two-dimensional 5-state Potts model, which in the pure state undergoes a phase transition first-order. Numerical studies have revealed that an insignificant quenched disorder, realized in the form of nonmagnetic impurities, can change the order of phase transition in magnetic systems described by the two-dimensional 5-state Potts model on a square lattice, for which a phase transition of the first-order is observed in a homogeneous state. It is shown that such a phase change the transition is due to the fact that nonmagnetic disorder prevents the coexistence of local phases characteristic of a phase transition of the first-order at T=Tl. Keywords: phase transitions, nonmagnetic disorder, Potts model, Monte Carlo, symmetry.

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Shaginyan, V. R., J. G. Han, and J. Lee. "Fermion condensation quantum phase transition versus conventional quantum phase transitions." Physics Letters A 329, no. 1-2 (August 2004): 108–15. http://dx.doi.org/10.1016/j.physleta.2004.06.065.

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Li, Jia Jie, Armen Sedrakian, and Mark Alford. "Relativistic Hybrid Stars with Sequential First-order Phase Transitions in Light of Multimessenger Constraints." Astrophysical Journal 944, no. 2 (February 1, 2023): 206. http://dx.doi.org/10.3847/1538-4357/acb688.

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Abstract In this work, we consider the properties of compact stars in which quark matter has low- and high-density phases that are separated by a first-order phase transition. Thus, unlike the commonly considered case of a single phase transition from hadronic to quark matter, our models of hybrid stars contain sequential phase transitions from hadronic matter to low- and then to high-density quark matter phases. We extend our previous study of the parameter space of hybrid stars with a single phase transition to those with sequential phase transitions, taking into account the constraints on the mass and radius of neutron stars from the NICER experiment, the experimental inferences of the neutron skin thickness of the lead nucleus by the PREX-II experiment, and constraints on the tidal deformability from the gravitational-wave event GW170817. We determine the range of the masses for which both twin and triplet configurations, i.e., identical-mass stars with two and three different values of radii, arise.

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Загребин, М. А., М. В. Матюнина, А. Б. Кошкин, В. Д. Бучельников, and В. В. Соколовский. "Фазовые превращения в сплавах Fe-=SUB=-100-x-=/SUB=-Si-=SUB=-x-=/SUB=-: исследования ab initio." Физика твердого тела 62, no. 5 (2020): 655. http://dx.doi.org/10.21883/ftt.2020.05.49224.24m.

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In present work, on the basis of structural and magnetic phase transition temperatures estimated theoretically from the first principles, the concentration phase diagram for Fe100-xSix (9.375 ≤ x ≤ 25.0 at.%) was plotted. Structural phase transition temperatures for the experimentally observed crystal structures were obtained from the structural optimization. The Curie temperatures were estimated from mean field approximation using ab initio calculated exchange coupling constants. Both structural and magnetic phase transitions temperatures are found in qualitative agreement with the experiment. For the whole considered concentration range, structural transitions from the ordered cubic to fully disordered through partially disordered one are appeared with temperature increasing. As for magnetic transformations, ferromagnetic-paramagnetic transition is observed for all compositions, however, it happens in different crystal phases.

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Sierant, Piotr, Giuliano Chiriacò, Federica M. Surace, Shraddha Sharma, Xhek Turkeshi, Marcello Dalmonte, Rosario Fazio, and Guido Pagano. "Dissipative Floquet Dynamics: from Steady State to Measurement Induced Criticality in Trapped-ion Chains." Quantum 6 (February 2, 2022): 638. http://dx.doi.org/10.22331/q-2022-02-02-638.

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Quantum systems evolving unitarily and subject to quantum measurements exhibit various types of non-equilibrium phase transitions, arising from the competition between unitary evolution and measurements. Dissipative phase transitions in steady states of time-independent Liouvillians and measurement induced phase transitions at the level of quantum trajectories are two primary examples of such transitions. Investigating a many-body spin system subject to periodic resetting measurements, we argue that many-body dissipative Floquet dynamics provides a natural framework to analyze both types of transitions. We show that a dissipative phase transition between a ferromagnetic ordered phase and a paramagnetic disordered phase emerges for long-range systems as a function of measurement probabilities. A measurement induced transition of the entanglement entropy between volume law scaling and sub-volume law scaling is also present, and is distinct from the ordering transition. The two phases correspond to an error-correcting and a quantum-Zeno regimes, respectively. The ferromagnetic phase is lost for short range interactions, while the volume law phase of the entanglement is enhanced. An analysis of multifractal properties of wave function in Hilbert space provides a common perspective on both types of transitions in the system. Our findings are immediately relevant to trapped ion experiments, for which we detail a blueprint proposal based on currently available platforms.

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Nikolaev, P. N. "Phase transition face-centered cubic crystal — homogeneous phase in helium." Seriya 3: Fizika, Astronomiya, no. 2_2024 (May 2, 2024): 2420102–1. http://dx.doi.org/10.55959/msu0579-9392.79.2420102.

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In this work, the characteristics of the phase transition face-centered cubic crystal — homogeneous phase in helium are calculated based on the correlation cell-cluster expansion. The theoretical data were compared with experimental data and good agreement was obtained. It is discussed the use of data on phase transitions in helium to estimate thermodynamic characteristics phase transition in a quantum system of hard spheres.

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Florêncio, Odila, Paulo Sergio Silva, José Antônio Eiras, Ducinei Garcia, and Eriton Rodrigo Botero. "Study of the Anelastic Behavior of PZT and PLZT Ferroelectric Ceramics." Defect and Diffusion Forum 326-328 (April 2012): 719–24. http://dx.doi.org/10.4028/www.scientific.net/ddf.326-328.719.

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The anelastic behavior of the ferroelectric ceramics (Pb)(Zr/Ti)O3(PZT) and (Pb/La)(Zr/Ti)O3(PLZT), with Zr/Ti = 65/35, La = 5 at.% and 8 at.%, was investigated in the region of the ferroelectric phase transitions. Anelastic spectroscopy experiments were performed in an acoustic elastometer system, operating in a kilohertz bandwidth, at temperatures rising from 300 K to 770 K, at a heating rate of 1 K/min, under pressure of 10-5mbar. Anelastic measurements on PZT showed only one anomaly, associated with the occurrence of a ferroelectric-paraelectric phase transition, while the PLZT data showed two anomalies, which were associated with the following transitions: the ferroelectric-paraelectric phase transition and a ferro-ferroelectric phase transition between distinct rhombohedral ferroelectric phases. The behavior of the relative variation of the elastic moduli with temperature, near the phase transitions, which describes the change in the type of coupling between strain and the order parameter in ferroelectric-paraelectric phase transition, with the increase of lanthanum amount and, linear coupling in the strain and order parameter type to PZT ceramic and linear coupling in the strain but quadratic in order parameter type for PLZT ceramics.

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Dixon, Charlotte A. L., Jason A. McNulty, Steven Huband, Pamela A. Thomas, and Philip Lightfoot. "Unprecedented phase transition sequence in the perovskite Li0.2Na0.8NbO3." IUCrJ 4, no. 3 (March 8, 2017): 215–22. http://dx.doi.org/10.1107/s2052252517002226.

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The perovskite Li0.2Na0.8NbO3is shown, by powder neutron diffraction, to display a unique sequence of phase transitions at elevated temperature. The ambient temperature polar phase (rhombohedral, space groupR3c) transformsviaa first-order transition to a polar tetragonal phase (space groupP42mc) in the region 150–300°C; these two phases correspond to Glazer tilt systemsa−a−a−anda+a+c−, respectively. At 500°C a ferroelectric–paraelectric transition takes place fromP42mctoP42/nmc, retaining thea+a+c−tilt. Transformation to a single-tilt system,a0a0c+(space groupP4/mbm), occurs at 750°C, with the final transition to the aristotype cubic phase at 850°C. TheP42mcandP42/nmcphases have each been seen only once and twice each, respectively, in perovskite crystallography, in each case in compositions prepared at high pressure.

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FENG, HONG-JIAN, XIAOYUN HU, and HUIJUAN CHEN. "STRUCTURAL AND MAGNETIC PHASE TRANSITIONS OF BiFeO3 INDUCED BY PRESSURE." Functional Materials Letters 06, no. 03 (May 28, 2013): 1350026. http://dx.doi.org/10.1142/s1793604713500264.

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First-principles calculations on BiFeO3 under low-pressure region show that the rhombohedral-monoclinic and rhombohedral-orthorhombic phase transitions can be found around the critical pressure value, ~9 GPa.We suggest that the structure involve the combination of these three phases and change to the pure orthorhombic phase gradually as pressure is beyond the critical value. Moreover, it is a first-order structural phase transition, accompanied with antiferromagnetic–ferromagnetic transition.

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Murtazaev, A. K., and Zhavrail G. Ibaev. "The Investigation of Critical Properties of the Transition from Modulated Phase into Paramagnetic Phase." Solid State Phenomena 233-234 (July 2015): 30–33. http://dx.doi.org/10.4028/www.scientific.net/ssp.233-234.30.

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The anisotropic Ising model with competing interactions in the region of transition from a modulated phase into paramagnetic state is investigated by the Monte-Carlo methods. By means of histogram analysis and the finite-size scaling method, the modulated – paramagnetic phase transition is shown to be a second order phase transition. Critical parameters and temperatures of phase transitions in this region are calculated.

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Alert, Ricard, Pietro Tierno, and Jaume Casademunt. "Mixed-order phase transition in a colloidal crystal." Proceedings of the National Academy of Sciences 114, no. 49 (November 20, 2017): 12906–9. http://dx.doi.org/10.1073/pnas.1712584114.

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Mixed-order phase transitions display a discontinuity in the order parameter like first-order transitions yet feature critical behavior like second-order transitions. Such transitions have been predicted for a broad range of equilibrium and nonequilibrium systems, but their experimental observation has remained elusive. Here, we analytically predict and experimentally realize a mixed-order equilibrium phase transition. Specifically, a discontinuous solid–solid transition in a 2D crystal of paramagnetic colloidal particles is induced by a magnetic field H. At the transition field Hs, the energy landscape of the system becomes completely flat, which causes diverging fluctuations and correlation length ξ∝|H2−Hs2|−1/2. Mean-field critical exponents are predicted, since the upper critical dimension of the transition is du=2. Our colloidal system provides an experimental test bed to probe the unconventional properties of mixed-order phase transitions.

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Siegel, D. P., W. J. Green, and Y. Talmon. "Studying the mechanism of Lα/HII and Lα/QII phase transmissions in phospholipid liquid crystals with temperature-jump cryo-TEM." Proceedings, annual meeting, Electron Microscopy Society of America 52 (1994): 432–33. http://dx.doi.org/10.1017/s0424820100169894.

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The transitions between lamellar (Lα), inverted cubic (QII), and inverted hexagonal (HII) liquid crystalline phases can be very rapid, despite drastic changes in system topology. The Lα phase is a stack of flat lipid bilayers, the HII phase is a hexagonal array of inverted rod micelles, and the QII phase is a lipid bilayer labyrinth with the geometry of an infinite periodic minimal surface. The mechanism of the transitions from the Lα a phase are of particular interest: they start with interbilayer events that are related to the process of biomembrane fusion, a ubiquitous and essential process in cellular function. Previous theoretical work suggested two possible mechanisms for these transitions. We have studied these transitions using time-resolved cryo-TEM. Earlier, we used on-the-grid mixing techniques to trigger the transition and observe some of the intermediates that form within seconds. Here we use a novel temperature-jump cryo-TEM technique which triggers the phase transition several milliseconds before vitrification. We extend the initial results obtained with this apparatus and reinterpret them in terms of a new theory of the transition mechanism.

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ALBEVERIO, SERGIO, YURI KONDRATIEV, YURI KOZITSKY, and MICHAEL RÖCKNER. "PHASE TRANSITIONS AND QUANTUM EFFECTS IN ANHARMONIC CRYSTALS." International Journal of Modern Physics B 26, no. 11 (April 30, 2012): 1250063. http://dx.doi.org/10.1142/s0217979212500634.

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The most important recent results in the theory of phase transitions and quantum effects in quantum anharmonic crystals are presented and discussed. In particular, necessary and sufficient conditions for a phase transition to occur at some temperature are given in the form of simple inequalities involving the interaction strength and the parameters describing a single oscillator. The main characteristic feature of the theory is that both mentioned phenomena are described in one and the same setting, in which thermodynamic phases of the model appear as probability measures on path spaces. Then the possibility of a phase transition to occur is related to the existence of multiple phases at the same values of the relevant parameters. Other definitions of phase transitions, based on the nondifferentiability of the free energy density and on the appearance of ordering, are also discussed.

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33

Zarychta, Bartosz, Zbigniew Czapla, Janusz Przesławski, and Przemysław Szklarz. "Structure, ferroelasticity and Goldilocks zone phase transitions in C3H5N2Al(SO4)2·6H2O." Acta Crystallographica Section B Structural Science, Crystal Engineering and Materials 77, no. 2 (March 12, 2021): 225–31. http://dx.doi.org/10.1107/s2052520621001256.

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The single crystal growth and sequence of reversible phase transition are described for C3H5N2Al(SO4)2·6H2O. Thermal and structural analyses combined with dielectric studies and optical observations revealed the structural phase transition at T 1 = 339/340 K (I↔II) and T 2 = 347/348 K (II↔III) on heating and cooling, respectively. Both phase transitions are of the first-order type. The symmetry changes from monoclinic to trigonal phase. At 293 K, the large crystals are usually divided into numerous domains of the ferroelastic type that disappear above T 1 on heating and reappear below T 1 on cooling. The domain structure pattern is characteristic for the transition between trigonal and monoclinic phases. The changes of entropy and clear increase of permittivity at T 1 provide evidence for the order–disorder character of this phase transition. The transition at T 2 seems to be displacive.

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34

Lu, Ping, Jiadong Zhou, Xinling Liu, Zongtao Zhang, Fangfang Xu, Linlin Zhang, Xinliang Mou, Jingwei Feng, Yanfeng Gao, and Jingtai Zhao. "Characterization of phase-transition-induced micro-domain structures in vanadium dioxide." Journal of Applied Crystallography 47, no. 2 (March 28, 2014): 732–38. http://dx.doi.org/10.1107/s1600576714002854.

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The displacive structural phase transition of vanadium dioxide (VO2) from the high-temperature tetragonal rutile (R) phase to the low-temperature monoclinic M1 or M2 phase may induce the formation of a variety of domain structures. Here, all possible types of phase-transition-induced domain structures of the M1 and M2 phases have been theoretically formulated by using a general space group method. The predicted domain structures of the M1 phase, including mirror or rotation twins and antiphase domains, have been confirmed by transmission electron microscopy observation of VO2powders and films, while the antiphase domains have never been involved in previous studies. The changes undergone by domain structures during a thermal or electron-beam-induced phase transition have been investigated. These results may suggest the potential influence of domain structures on the nucleation and progress of phase transitions, which unambiguously affect the hysteresis behavior of the first-order transition of VO2.

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35

Haines, Julian, and D. F. R. Gilson. "Phase transitions in solid cycloheptene." Canadian Journal of Chemistry 68, no. 4 (April 1, 1990): 604–11. http://dx.doi.org/10.1139/v90-093.

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The phase transition behaviour of cycloheptene has been investigated by differential scanning calorimetry, proton spin-lattice relaxation, and vibrational spectroscopy (infrared and Raman). Two solid–solid phase transitions were observed, at 154 and 210 K, with transition enthalpies and entropies of 5.28 and 0.71 kJ mol−1 and 34.3 and 3.4 JK−1, respectively. Cycloheptene melted at 217 K with an entropy of melting of 4.5 JK−1 mol−1. The bands in the vibrational spectra of the two high temperature phases were broad and featureless, characteristic of highly disordered phases. The presence of other conformers, in addition to the chair form, was indicated from bands in the spectra. The ring inversion mode was highly phase dependent and exhibited soft mode type behaviour prior to the transition from the low temperature phase. The low frequency Raman spectra (external modes) of these phases indicated that the molecules are undergoing isotropic reorientation. In the low temperature phase, the vibrational bands were narrow; the splitting of the fundamentals into two components and the presence of nine external modes are consistent with unit cell symmetry of either C2 or Cs with two molecules per primitive unit cell. A glassy state can be produced from the intermediate phase and the vibrational spectra were very similar to those of the high temperature phases, indicating that static disorder was present. The barriers to reorientation, as obtained from proton spin-lattice relaxation measurements, are 9.0 kJ mol−1 in both the high temperature phases, and 15.4 kJ mol−1 in the low temperature, ordered phase. Keywords: cycloheptene, phase transition, differential scanning calorimetry, NMR, vibrational spectroscopy.

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36

Arakawa, Yuki, and Yuto Arai. "Photoinduced Phase Transitions of Imine-Based Liquid Crystal Dimers with Twist–Bend Nematic Phases." Materials 17, no. 13 (July 3, 2024): 3278. http://dx.doi.org/10.3390/ma17133278.

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Photoisomerizable molecules in liquid crystals (LCs) allow for photoinduced phase transitions, facilitating applications in a wide variety of photoresponsive materials. In contrast to the widely investigated azobenzene structure, research on the photoinduced phase-transition behavior of imine-based LCs is considerably limited. We herein report the thermal and photoinduced phase-transition behaviors of photoisomerizable imine-based LC dimers with twist–bend nematic (NTB) phases. We synthesize two homologous series of ester- and thioether-linked N-(4-cyanobenzylidene)aniline-based bent-shaped LC dimers with an even number of carbon atoms (n = 2, 4, 6, 8, and 10) in the central alkylene spacers, namely, CBCOOnSBA(CN) and CBOCOnSBA(CN), possessing oppositely directed ester linkages, C=OO and OC=O, respectively. Their thermal phase-transition behavior is examined using polarizing optical microscopy and differential scanning calorimetry. All dimers form a monotropic NTB phase below the temperature of the conventional nematic (N) phase upon cooling. Remarkably, the NTB phases of CBCOOnSBA(CN) (n = 2, 4, 6, and 8) and CBOCOnSBA(CN) (n = 6 and 8) supercool to room temperature and vitrify without crystallization. In addition, the phase-transition temperatures and entropy changes of CBCOOnSBA(CN) are lower than those of CBOCOnSBA(CN) at the same n. Under UV light irradiation, the NTB and N phases transition to the N and isotropic phases, respectively, and reversibly return to their initial LC phases when the UV light is turned off.

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Chandra, Dhanesh, Renee A. Lynch, Wei Ding, and John J. Tomlinson. "Phase Diagram Studies on Neopentylglycol and Pentaerythritol-Thermal Energy Storage Materials." Advances in X-ray Analysis 33 (1989): 445–52. http://dx.doi.org/10.1154/s037603080001987x.

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AbstractPentaerythritol (PE) and neopentylglycol (NPG) are organic molecular crystals which have hydrogen-bonded lattices with layered- and chain-type structures, respectively. The PE undergoes solid-state phase transitions at 416K, from tetragonal to a cubic (γ’) structure and NPG also undergoes this transition at 317K from a monoclinic to a cubic (γ) structure. The phase transitions in binary PE-NPG solid solutions show more than one solid-solid transition in which the NPG-rich β transforms to γ at a constant temperature but the transition of the PE-rich a phase to γ’ passes through a two-phase field at a temperature that varies as a function of composition. Structural analyses by high-temperature x-ray diffractometry have revealed some new, interesting transitions. A phase diagram has been constructed for 0-30 mol% NPG in the PE-NPG system, using x-ray diffraction and differential scanning calorimetry results, and work is in progress to complete this diagram. The variation of lattice parameters as a function of temperature in the α, γ and γ’ phases for PE+20 mol% NPG are presented here, together with a discussion of phase transitions for certain compositions.

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38

Zhou, Ling. "Nanoparticles-Induced Phase Transitions in A(BC)₃ Miktoarm Star Copolymers." Advanced Materials Research 905 (April 2014): 23–27. http://dx.doi.org/10.4028/www.scientific.net/amr.905.23.

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Phase transitions induced by nanoparticles in A(BC)3 miktoarm star copolymers are investigated by using self-consistent field and density functional theories. With increasing nanoparticle concentration, a variety of phase transitions are observed, including the transition from a hexagonal lattice phase with beads at the interface to a core-shell hexagonal lattice phase, the transition from a core-shell hexagonal lattice phase to a three-color lamellar phase, and the transition from a lamellar phase with beads at the interface to a three-color lamellar phase. The results provide an effective control mechanism for obtaining the desired microstructures and realizing their transitions.

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Zienert, Tilo, and Christos Georgios Aneziris. "Thermal Expansion and Phase Transformation up to 1200 °C of Metastable Aluminas Produced by Flame Spraying." Crystals 13, no. 5 (April 29, 2023): 743. http://dx.doi.org/10.3390/cryst13050743.

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The transition aluminas δ1 and the cubic, non-spinel-type η-Al2O3 were detected in addition to α-Al2O3 in flame-sprayed material. Their transitions from room temperature up to 1200 °C were investigated by high-temperature XRD measurements. Structural changes with time and temperature were observed for all transition aluminas (η-, δ1- and θ-Al2O3). The phases followed the expected transition sequence of η→δ1→θ→α and showed mainly linear, temperature-independent transition rates. Based on the determined thermal expansion of the phases, it is proposed that the metastable transitions are at least partly mechanically induced. In addition, a second-order phase transition from η→θ might be indicated around 1050–1075 °C by the determined trends of density.

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40

Aghamohammadi, Amir. "Constraints and phase transitions: Phase transition in infinite compound Atwood’s machine." Physica A: Statistical Mechanics and its Applications 506 (September 2018): 873–79. http://dx.doi.org/10.1016/j.physa.2018.05.002.

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41

Liu, Wendi, Yan Yang, Qunke Xia, Yu Ye, Zhongping Wang, Peipei Zhang, and Guowu Li. "Water decreases displacive phase transition temperature in alkali feldspar." European Journal of Mineralogy 30, no. 6 (December 20, 2018): 1071–81. http://dx.doi.org/10.1127/ejm/2018/0030-2775.

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42

Ovsyuk, Nikolay N., and Sergei V. Goryainov. "Role of internal pressure in a ferroelastic phase transition." European Journal of Mineralogy 17, no. 2 (April 29, 2005): 215–22. http://dx.doi.org/10.1127/0935-1221/2005/0017-0215.

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43

Matsuyama, Akihiko. "Volume Phase Transitions of Heliconical Cholesteric Gels under an External Field along the Helix Axis." Gels 6, no. 4 (November 16, 2020): 40. http://dx.doi.org/10.3390/gels6040040.

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We present a mean field theory to describe cholesteric elastomers and gels under an external field, such as an electric or a magnetic field, along the helix axis of a cholesteric phase. We study the deformations and volume phase transitions of cholesteric gels as a function of the external field and temperature. Our theory predicts the phase transitions between isotropic (I), nematic (N), and heliconical cholesteric (ChH) phases and the deformations of the elastomers at these phase transition temperatures. We also find volume phase transitions at the I−ChH and the N−ChH phase transitions.

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44

Gagor, Anna, Maciej Wojtaś, Adam Pietraszko, and Ryszard Jakubas. "From six- to five-coordinated SbIII in [(CH3)3PH]3[Sb2Cl9]: transition pathways from single-crystal X-ray diffraction." Acta Crystallographica Section B Structural Science 64, no. 5 (September 16, 2008): 558–66. http://dx.doi.org/10.1107/s0108768108027353.

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[(CH3)3PH]3[Sb2Cl9] experiences four phase transitions which were found by means of calorimetry, thermogravimetry and X-ray diffraction. The crystal structure was solved in the space group P63/mmc at 382 K (phase I), Pnam at 295 K (phase II) and Pna21 at 175 K (phase V). We observed an unusual increase in symmetry from the monoclinic to the orthorhombic form at the IV\rightarrowV transition. The parent hexagonal high-temperature phase I consists of highly disordered [(CH3)3PH]+ cations and [Sb2Cl9]3− anions with an octahedral environment of SbIII. The transition from phases I to II is associated with the ordering of [(CH3)3PH]+ cations. Moreover, the successive transformations from phases I to V are related to the change in the arrangement of Cl atoms in [Sb2Cl9]3− anions from the discrete `face-sharing bioctahedra' (phase I) to two corner-sharing square pyramids. A mechanism for the phase transitions is proposed. It is observed that weak C—H...Cl interactions are responsible for the structure arrangement in low-temperature phases.

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45

Sherrill, Max D., and Walter L. Trikosko. "Josephson phase transition." Physical Review B 32, no. 11 (December 1, 1985): 7590–93. http://dx.doi.org/10.1103/physrevb.32.7590.

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46

Norman, G. E. "Plasma Phase Transition." Contributions to Plasma Physics 41, no. 2-3 (March 2001): 127–30. http://dx.doi.org/10.1002/1521-3986(200103)41:2/3<127::aid-ctpp127>3.0.co;2-8.

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47

Kazama, Takuto, Minoru Maeda, Kouichi Takase, Yoshiki Takano, and Tadataka Watanabe. "Electric and Magnetic Properties of Transition-Metal Carbide Sc₃TC₄ (T=Co, Ru, Os)." Solid State Phenomena 257 (October 2016): 34–37. http://dx.doi.org/10.4028/www.scientific.net/ssp.257.34.

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We investigate electric and magnetic properties of quasi-one-dimensional transition-metal carbides Sc3TC4 (T = Co, Ru, and Os), and their mixed crystals Sc3(Co1-xRux)C4 and Sc3(Ru1-xOsx)C4. Sc3CoC4 exhibits successive phase transitions of charge-density-wave transition at TCDW ~ 140 K, Peierls-like structural transition at Ts ~ 70 K, and superconducting transition at Tc ~ 5 K. Sc3RuC4 and Sc3OsC4 exhibit a phase transition at T* ~ 220 K and 250 K, respectively, which should occur in the low-dimensional electronic structure. For Sc3CoC4, it is revealed by the investigation of the electric and magnetic properties of Sc3(Co1-xRux)C4 that the phase transitions at TCDW, Ts, and Tc exhibit different robustness against Ru doping. For Sc3RuC4 and Sc3OsC4, it is revealed by the investigation of the electric and magnetic properties of Sc3(Ru1-xOsx)C4 that an identical kind of phase transition occurs at T*. Additionally, the present study reveals that the phase transition at T* in Sc3RuC4 and Sc3OsC4 is inherently different from the phase transitions at TCDW, Ts, and Tc in Sc3CoC4.

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48

Yang, X. M., G. Zhang, and Z. Song. "Phase transition in phase transition lines of quantum XY model." Journal of Physics: Condensed Matter 31, no. 24 (April 2, 2019): 245401. http://dx.doi.org/10.1088/1361-648x/ab0f04.

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Zhu, Jing-Min. "Quantum phase transitions in composite matrix product states of one-dimensional spin-1/2 chains." International Journal of Modern Physics B 29, no. 09 (April 7, 2015): 1550071. http://dx.doi.org/10.1142/s021797921550071x.

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For matrix product states of one-dimensional spin-1/2 chains, we investigate the properties of quantum phase transition of the proposed composite system. We find that the system has three different ferromagnetic phases, one line of the two ferromagnetic phases coexisting equally describes the paramagnetic state, and the other two lines of two ferromagnetic phases coexisting equally describe the ferrimagnetic states, while the three phases coexisting equally point describes the ferromagnetic state. Whether on phase transition lines or at the phase transition point, the system is always in an isolated mediate-coupling state, the physical quantities are discontinuous and the system has long-range correlation and has long-range classical correlation and long-range quantum correlation. We believe that our work is helpful for comprehensively and profoundly understanding the quantum phase transitions, and of some certain guidance and enlightening on the classification and measure of quantum correlation of quantum many-body systems.

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Kong, Xiangru, Wei Luo, Linyang Li, Mina Yoon, Tom Berlijn, and Liangbo Liang. "Floquet band engineering and topological phase transitions in 1T’ transition metal dichalcogenides." 2D Materials 9, no. 2 (January 31, 2022): 025005. http://dx.doi.org/10.1088/2053-1583/ac4957.

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Abstract Using ab initio tight-binding approaches, we investigate Floquet band engineering of the 1T’ phase of transition metal dichalcogenides (MX2, M = W, Mo and X = Te, Se, S) monolayers under the irradiation with circularly polarized light. Our first principles calculations demonstrate that light can induce important transitions in the topological phases of this emerging materials family. For example, upon irradiation, Te-based MX2 undergoes a phase transition from quantum spin Hall (QSH) semimetal to time-reversal symmetry broken QSH insulator with a nontrivial band gap of up to 92.5 meV. On the other hand, Se- and S-based MX2 undergoes the topological phase transition from the QSH effect to the quantum anomalous Hall effect and into trivial phases with increasing light intensity. From a general perspective, this theoretical work brings further insight into non-equilibrium topological systems.

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Journal articles on the topic 'Phase transition'

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