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Topological semimetal may have potential applications like topological qubits, spintronics and quantum computations. Efficient heat dissipation is a key factor for the reliability and stability of topological semimetal-based nano-electronics devices, which is closely related to high thermal conductivity. In this work, the elastic properties and lattice thermal conductivity of TaN are investigated by first-principles calculations and the linearized phonon Boltzmann equation within the single-mode relaxation time approximation (RTA). According to the calculated bulk modulus, shear modulus and $C_{44}$, TaN can be regarded as a potential incompressible and hard material. The room-temperature lattice thermal conductivity is predicted to be 838.62 $mathrm{W m^{-1} K^{-1}}$ along a axis and 1080.40 $mathrm{W m^{-1} K^{-1}}$ along c axis, showing very strong anisotropy. It is found that the lattice thermal conductivity of TaN is several tens of times higher than one of other topological semimetal, such as TaAs, MoP and ZrTe, which is due to very longer phonon lifetimes for TaN than other topological semimetal. The very different atomic masses of Ta and N atoms lead to a very large acoustic-optical band gap, and then prohibits the scattering between acoustic and optical phonon modes, which gives rise to very long phonon lifetimes. Based on mass difference factor, the WC and WN can be regarded as potential candidates with ultrahigh lattice thermal conductivity. Calculated results show that isotope scattering has little effect on lattice thermal conductivity, and that phonon with mean free path(MFP) larger than 20 (80) $mathrm{mu m}$ at 300 K has little contribution to the total lattice thermal conductivity. This work implies that TaN-based nano-electronics devices may be more stable and reliable due to efficient heat dissipation.
By means of extensive ab initio calculations, a new two-dimensional (2D) atomic material tin selenide monolayer (coined as tinselenidene) is predicted to be a semiconductor with an indirect gap (1.45 eV) and a high hole mobility (of order 10000 cm2V-
The Weyl semimetal NbP exhibits an extremely large magnetoresistance (MR) and an ultra-high mobility. The large MR originates from a combination of the nearly perfect compensation between electron- and hole-type charge carriers and the high mobility,
Allotropes of carbon, such as diamond and graphene, are among the best conductors of heat. We monitored the evolution of thermal conductivity in thin graphite as a function of temperature and thickness and found an intimate link between high conducti
Bulk gallium oxide (Ga2O3) has been widely used in lasers, dielectric coatings for solar cells, deep-ultraviolet transistor applications due to the large band gap over 4.5 eV. With the miniaturization of electronic devices, atomically thin Ga2O3 mono
Quantifying the correlation between the complex structures of amorphous materials and their physical properties has been a long-standing problem in materials science. In amorphous Si, a representative covalent amorphous solid, the presence of a mediu