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We propose an algebraic form for the density of states of quarks and gluons in a Quark-Gluon Plasma (QGP) fireball in quasi-equilibrium with a hadronic medium as $\rho(k)= \frac {\alpha}{k} + {\beta}k + {\delta}k^{2}$, and determine the…

High Energy Physics - Phenomenology · Physics 2011-03-28 R. Ramanathan , Agam K. Jha , S. S. Singh

We present the vibrational properties and phonon dispersion for quasi-2D hybrid organic-inorganic perovskites (BA)$_2$CsPb$_2$I$_7$, (HA)$_2$CsPb$_2$I$_7$, (BA)$_2$(MA)Pb$_2$I$_7$, and (HA)$_2$(MA)Pb$_2$I$_7$ calculated from first…

Materials Science · Physics 2024-01-23 Emily Y. Chen , Bartomeu Monserrat

We present an \textit{ab initio} framework to calculate anharmonic phonon frequency and phonon lifetime that is applicable to severely anharmonic systems. We employ self-consistent phonon (SCPH) theory with microscopic anharmonic force…

Materials Science · Physics 2015-08-20 Terumasa Tadano , Shinji Tsuneyuki

The massively parallel computation of absolute binding free energy with a well-equilibrated system (MP-CAFEE) has been developed [H. Fujitani, Y. Tanida, M. Ito, G. Jayachandran, C. D. Snow, M. R. Shirts, E. J. Sorin, and V. S. Pande, J.…

Soft Condensed Matter · Physics 2009-11-13 Yoshiaki Tanida , Masakatsu Ito , Hideaki Fujitani

Harnessing the power of low-dimensional materials in thermal applications calls for a solid understanding of the anomalous thermal properties of such systems. We analyze thermal conduction in one-dimensional systems by determining the…

Computational Physics · Physics 2015-12-21 K. Sääskilahti , J. Oksanen , S. Volz , J. Tulkki

Recently, nanofluidics experiments have been used to characterize the behavior of single DNA molecules confined to narrow slits etched with arrays of nanopits. Analysis of the experimental data relies on analytical estimates of the…

Soft Condensed Matter · Physics 2024-09-09 James M. Polson , Matthew Kozma

We performed density functional calculations to estimate the formation energies of intermetallic alloys. We used two semilocal approximations, the generalized gradient approximation (GGA) by Perdew-Burke-Ernzerhof (PBE) and the strongly…

Materials Science · Physics 2020-11-25 Niraj K. Nepal , Santosh Adhikari , Bimal Neupane , Adrienn Ruzsinszky

Obtaining the free energy of large molecules from quantum mechanical energy functions is a longstanding challenge. We describe a method that allows us to estimate, at the quantum mechanical level, the harmonic contributions to the…

Chemical Physics · Physics 2023-03-07 Alec F. White , Chenghan Li , Xing Zhang , Garnet Kin-Lic Chan

Magnetic layered materials have emerged recently as promising systems to introduce magnetism in structures based on two-dimensional (2D) materials and to investigate exotic magnetic ground states in the 2D limit. In this work, we apply high…

One of the most powerful strategies to address properties of real many-body systems is to incorporate data obtained for models, for example, to use data of the homogeneous electron gas in order to build the Local Density Approximation for…

Materials Science · Physics 2026-05-05 Muhammed Hüseyin Güneş , Ayoub Aouina , Vitaly Gorelov , Matteo Gatti , Lucia Reining

In this work we study a completely degenerated fermion gas at zero temperature within a semiclassical approximation for the Hamiltonian arising in polymer quantum mechanics. Polymer quantum systems are quantum mechanical models quantized in…

Solar and Stellar Astrophysics · Physics 2015-06-22 Guillermo Chacon-Acosta , Hector Hernandez-Hernandez

Previous analysis of AstroSat observations of the black hole system MAXI J1535-571, have revealed the presence of a strong Quasi-Periodic Oscillation (QPO) whose frequency is correlated with the high energy spectral index. Here, we fit the…

High Energy Astrophysical Phenomena · Physics 2022-06-15 Akash Garg , Ranjeev Misra , Somasri Sen

Phonon drag may be harnessed for thermoelectric generators and devices. Here, we demonstrate the geometric control of the phonon-drag contribution to the thermopower. In nanometer-thin electrically conducting $\beta$-Ga$_2$O$_3$ films…

Mesoscale and Nanoscale Physics · Physics 2025-08-26 J. Boy , R. Mitdank , A. Popp , Z. Galazka , S. F. Fischer

We present an implementation of alchemical free energy simulations at the quantum mechanical level by directly interpolating the electronic Hamiltonian. The method is compatible with any level of electronic structure theory and requires…

Chemical Physics · Physics 2024-09-02 Chenghan Li , Xing Zhang , Garnet Kin-Lic Chan

A method for performing variable-width (thawed) Gaussian wavepacket (GWP) variational dynamics on machine-learned potentials is presented. Instead of fitting the potential energy surface (PES), the anharmonic correction to the global…

Chemical Physics · Physics 2024-12-17 Rami Gherib , Ilya G. Ryabinkin , Scott N. Genin

We examine a hot pion gas by including medium modifications of the two-body scattering amplitude as well as mean-field effects selfconsistently. In contrast to earlier calculations, the in-medium T-matrix is rather close to the free one…

Nuclear Theory · Physics 2009-10-22 R. Rapp , J. Wambach

We present a fast and accurate method to calculate vibrational properties for mechanically unstable high temperature phases that suffer from imaginary frequencies at zero temperature. The method is based on standard finite-difference…

Materials Science · Physics 2015-06-03 Nikolas Antolin , Oscar D. Restrepo , Wolfgang Windl

The General Spectral Modeling (GSM) code employs the quasi-static approximation, a standard, low-density methodology that assumes the ionization balance is separable from a determination of the excited-state populations that give rise to…

Atomic Physics · Physics 2008-11-26 Justin Oelgoetz , Christopher J. Fontes , Hong Lin Zhang , Anil K. Pradhan

The topological effects of phonons have been extensively studied in various materials, particularly in the wide-bandgap semiconductor GaN, which has the potential to improve heat dissipation in power electronics due to its intrinsic,…

Materials Science · Physics 2023-10-17 Daosheng Tang

In this paper, an improved quasi-particle model is presented. Unlike the previous approach of establishing quasi-particle model, we introduce a classical background field (it is allowed to depend on the temperature) to deal with the…

High Energy Physics - Phenomenology · Physics 2015-06-04 Jing Cao , Yu Jiang , Wei-min Sun , Hong-shi Zong