相关论文: Temperature-dependent elastic constants of thorium…
We report resonant ultrasound spectroscopy (RUS), dilatometry/magnetostriction, magnetotransport, magnetization, specific heat, and $^{119}$Sn M\"ossbauer spectroscopy measurements on SnTe and Sn$_{0.995}$Cr$_{0.005}$Te. Hall measurements…
Brillouin spectroscopic measurements have been carried out on relaxor ferroelectric Pb(Zn1/3Nb2/3)0.85Ti0.15O3 (PZN-PT) single crystal over the temperature range 300-585 K. The longitudinal acoustic phonon begins to soften below 650 K,…
Understanding and simulating the thermodynamic and dynamical properties of materials affected by strong ionic anharmonicity is a central challenge in material science. Much interest is in material displaying critical displacive behaviour,…
A theory has been developed to interpret time-domain Brillouin scattering (TDBS) experiments involving coherent acoustic pulse (CAP) and light pulse beams propagating at an angle to each other. It predicts the influence of the directivity…
We review our recent development of a first-principles lattice dynamics method that can treat anharmonic effects nonperturbatively. The method is based on the self-consistent phonon theory and temperature-dependent phonon frequencies can be…
The sound velocity in selected liquid alloys of the isomorphous Bi-Sb system was measured as a function of temperature to a high accuracy of 0.2%. The sound velocity temperature coefficient, dlnc/dT, at the liquidus is found to vary…
Understanding and manipulating nanoscale energy transport and conversion processes are essential for diverse applications, ranging from thermoelectrics and energy harvesting to thermal management of microelectronics. While it has long been…
Elastic constants are central material properties, frequently reported in experimental and theoretical studies. While their computation is straightforward in the absence of thermal fluctuations, finite--temperature methods often suffer from…
Examining the physical properties of materials - particularly of toxic liquids - under a wide range of thermodynamic states is a challenging problem due to the extreme conditions the material has to be exposed to. Such temperature and…
The elastic moduli of vortex crystals in anisotropic superconductors are frequently involved in the investigation of their phase diagram and transport properties. We provide a detailed analysis of the harmonic eigenvalues (normal modes) of…
Single-crystal diffuse scattering data have been collected at room temperature on synthetic titanite using both neutrons and high-energy X-rays. A simple ball-and-springs model reproduces the observed diffuse scattering well, confirming its…
We present calculations of the millielectronvolt-scale x-ray scattering spectra of multilayered dynamic-compression targets comprising an unstructured ablator layer and a crystalline, textured sample layer. Our model builds on the classic…
Contactless, laser-based resonant ultrasound spectroscopy was utilized to monitor changes in elastic properties in single-crystalline NiTi shape memory alloy. It was observed that the elastic behavior of the temperature-induced B19$^\prime$…
The structural, dielectric and ferroelectric properties of lead-free (Na0.5-xKxBi0.5-xLax)TiO3 powders synthesized by sol-gel self-combustion method were investigated. Rietveld refinement of Synchrotron x-ray diffraction data confirms pure…
The pure CsPbBr$_3$ perovskite is an archetypal example of a strongly anharmonic crystal that poses a major challenge for computational methods to describe its thermodynamic properties. Its lattice dynamics exhibits characteristics of a…
In crystals, molecules thermally vibrate around the periodic lattice sites. Vibrational motions are well understood in terms of phonons, which carry heat and control heat transport. The situation is notably different in disordered solids,…
Two-dimensional (2D) ZrS2 monolayer (ML) has emerged as a promising candidate for thermoelectric (TE) device applications due to its high TE figure of merit, which is mainly contributed by its inherently low lattice thermal conductivity.…
We present the ab-initio thermoelastic properties of body-centered cubic molybdenum under extreme conditions obtained within the quasi-harmonic approximation including both the vibrational and the electronic thermal excitations…
Lead-free Ba0.9Sr0.1Ti0.9Sn0.1O3 (BSTSn) ceramic was prepared by the sol gel method. X-ray diffraction measurement at room temperature reveals the single-phase formation with tetragonal structure refined in the P4mm space group. Raman…
Single-crystal elastic moduli, Cij, and the B1-B2 phase transition of NaCl were investigated experimentally, using time-domain Brillouin scattering (TDBS), and theoretically, via density-functional-theory (DFT), to 41 GPa. Thus, we largely…