Article
Physics, Applied
Robert A. Robinson, Lujin Min, Seng Huat Lee, Peigang Li, Yu Wang, Jinguo Li, Zhiqiang Mao
Summary: In this study, researchers found a temperature-dependent violation of the WF law in the Heusler, ferromagnetic, Weyl semimetal Co2MnAl. The extreme magnitude and temperature dependence of the violation in Co2MnAl suggest that there may be multiple effects contributing to the violation in this system.
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2021)
Article
Physics, Nuclear
Kshitish Kumar Pradhan, Dushmanta Sahu, Ronald Scaria, Raghunath Sahoo
Summary: In this study, a hadron resonance gas with van der Waals interactions is investigated. Transport properties such as electrical and thermal conductivities are estimated by solving the Boltzmann transport equation, considering both attractive and repulsive interactions. The effects of baryochemical potential and temperature on these observables are explored, and comparisons are made with other theoretical models. Violation of the Wiedemann-Franz law is observed in the high-temperature regime of the hadron resonance gas, and diffusivities provide further insights into the system.
Article
Nanoscience & Nanotechnology
Jonah Waissman, Laurel E. Anderson, Artem Talanov, Zhongying Yan, Young J. Shin, Danial H. Najafabadi, Mehdi Rezaee, Xiaowen Feng, Daniel G. Nocera, Takashi Taniguchi, Kenji Watanabe, Brian Skinner, Konstantin A. Matveev, Philip Kim
Summary: The combination of reduced dimensionality, strong interactions, and topology in low-dimensional systems leads to many-body quantum phenomena. Thermal transport serves as a discriminating probe in quantum materials and devices, with the need for experimental methods to isolate electronic contributions. Measurements using noise thermometers and linear and nonlinear thermal transport reveal signatures of energy transport mediated by long-range interactions in one-dimensional electron systems.
NATURE NANOTECHNOLOGY
(2022)
Article
Materials Science, Multidisciplinary
Pardeep Kumar Tanwar, Md Shahin Alam, Mujeeb Ahmad, Dariusz Kaczorowski, Marcin Matusiak
Summary: The thermal conductivity (??) of the Weyl semimetal NbP was studied with the thermal gradient and magnetic field applied parallel to the [0 0 1] direction. At low temperatures, ??(B) exhibits large quantum oscillations with frequencies matching two determined from the Shubnikov???de Haas effect. These frequencies originate from the electron pocket enclosing a pair of Weyl nodes. The amplitude of the oscillatory component of the thermal conductivity is significantly larger than the corresponding value calculated from the electrical conductivity using the Wiedemann-Franz law, possibly due to the chiral zero sound effect.
Article
Chemistry, Multidisciplinary
Danial Majidi, Martin Josefsson, Mukesh Kumar, Martin Leijnse, Lars Samuelson, Herve Courtois, Clemens B. Winkelmann, Ville F. Maisi
Summary: The Wiedemann-Franz law states that charge conductance and the electronic contribution to heat conductance are proportional. However, our experiments show that the heat conduction can be significantly lower than the predicted value due to quantum confinement and energy-selective transport properties in a semiconductor nanostructure. This opens up new possibilities for independently tailoring the thermal and electrical conduction properties.
Article
Physics, Multidisciplinary
Xuebo Zhou, Ping Zheng, Wei Wu, Yu Sui, Jianlin Luo
Summary: CrP has unique physical properties due to the nonsymmorphic symmetry of the space group, resulting in a four-fold degenerate band crossing at the Y point of the Brillouin zone. We conducted various measurements on CrP, including heat capacity, electrical and thermal transport, and extracted the electron thermal conductivity. The normalized Lorentz number decreases below 160 K due to differences in energy and momentum relaxation time during electron-phonon inelastic scattering, but begins to recover below 25.6 K due to the dominance of elastic scattering between electrons and defects at low temperatures.
Article
Chemistry, Physical
Adam Rycerz
Summary: The 2016 experiment by Crossno et al. found that the thermal conductivity of graphene violates the WF law at low temperatures, attributed to interactions between particles. Even at temperatures of few- or sub-kelvin, significantly enhanced thermal conductivity should appear, even when neglecting the role of interactions. Numerical results obtained within the Landauer-Buttiker formalism also support this finding.
Article
Astronomy & Astrophysics
Wei-Han Hsiao
Summary: The study investigates the thermoelectric properties of mixed-dimensional quantum electrodynamics of relativistic Dirac fermions and Wilson-Fisher bosons, revealing their self-dual nature and ability to form nontrivial many-body phases under different parameter values. Using particle-vortex duality, a variety of thermoelectric relations for strongly interacting phases were derived, showing dependencies on the Seebeck tensor determinant and the Hall angle theta(H), among other parameters, at the self-dual point. The dual fermion description sheds light on how the Seebeck tensor of the bosonic theory varies according to the dynamic regime characterized by theta(H).
Article
Materials Science, Multidisciplinary
Erik D. Kountz, Jiecheng Zhang, Joshua A. W. Straquadine, Anisha G. Singh, Maja D. Bachmann, Ian R. Fisher, Steven A. Kivelson, Aharon Kapitulnik
Summary: ErTe3 serves as a model system to study thermal transport in layered charge density wave materials. Thermal diffusivity, resistivity, and specific-heat data show a sharp decrease in thermal conductivity at the CDW transition temperature, while resistivity changes more gradually. In the critical regime, the behavior corresponds to a strongly coupled electron-phonon critical soup where traditional description is not possible.
Article
Nanoscience & Nanotechnology
Zhihui Lei, Wendong Liu, Wenkui Xing, Yingyue Zhang, Yongjia Liu, Peng Tao, Wen Shang, Benwei Fu, Chengyi Song, Tao Deng
Summary: In this work, we observed the size-dependent behavior of filler on the thermal and electrical conductivities of nacre-like graphene-conjugated conducting polymer films and demonstrated the tunability of the Lorenz constant in such films. These films showed high thermal and electrical conductivities, as well as good electromagnetic interference shielding performance. The findings provide new insights for designing flexible graphene-conjugated polymers with customizable thermal and electrical properties.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Editorial Material
Chemistry, Physical
Xiao-Lei Shi, Zhi-Gang Chen
Summary: In a recent article published in Science Bulletin, Dong et al. reported a quasi-one-dimensional TlCu3Te2 bulk material with a high application-level room temperature ZT value of 1.3. This is attributed to the presence of a pancake-like Fermi pocket with a quasi-one-dimensional dispersion at the narrow band-gap edge, as well as a large, anharmonic quasi-one-dimensional lattice structure formed by heavy Tl+ ions and weakly bonded Cu+ ions.
Article
Chemistry, Inorganic & Nuclear
Long Chen, Linlin Zhao, Xiaole Qiu, Qinghua Zhang, Kai Liu, Qisheng Lin, Gang Wang
Summary: The new manganese-based quasi-one-dimensional material RbMn6Bi5 exhibits unique crystal structure and physical properties, including antiferromagnetism. It shows significant resistivity anisotropy and is confirmed to be a quasi-one-dimensional metal with possible helical antiferromagnetic configuration.
INORGANIC CHEMISTRY
(2021)
Article
Materials Science, Multidisciplinary
Maher Yazback, Jie-Xiang Yu, Shuanglong Liu, Long Zhang, Neil S. Sullivan, Hai-Ping Cheng
Summary: Using density functional theory, the study focused on the structural, magnetic, and electronic properties of the organometallic quantum magnet NiCl2-4SC(NH2)(2) (DTN). The research confirmed the quasi one-dimensional nature of the molecular crystal, quantum phase transitions, magnetic anisotropy, intermolecular exchange coupling, and magnetoelectric effect observed in experiments. Further analysis of the electronic structure provided insights into the underlying magnetic interactions and potential mechanisms causing the observed effects.
Article
Materials Science, Multidisciplinary
Li Liu, Lirong Liang, Liang Deng, Hanfu Wang, Guangming Chen
Summary: Organic thermoelectric materials have attracted attention due to their advantages of flexibility, light weight, processability, and adjustable molecular structure. However, the current trend of pursuing high electrical conductivity and power factor is misleading. This study discusses the existence of a constant Lorentz number for organic thermoelectric materials based on the Wiedemann-Franz law and an empirical relation, and proposes a modified figure of merit equation that includes the electronic contribution to thermal conductivity.
APPLIED MATERIALS TODAY
(2022)
Article
Chemistry, Physical
Miho Itoi, Toshikazu Nakamura, Yoshiya Uwatoko
Summary: We investigated the superconductivity of (TMTTF)(2)TaF6 under high pressure and discovered a superconducting state in a narrower pressure range compared to other salts. The unique pressure characteristics of (TMTTF)(2)TaF6 in the T-P phase diagram of (TMTTF)(2)PF6 were observed.
