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ABX₃-type nitride perovskites offer promising avenues for the future electronic industry, renowned for exceptional ferro- and piezo-electric properties with facile integration into prevalent nitride semiconductors. However, the paucity of in-depth investigations of thermal transport of nitride perovskites poses a substantial impediment to the practical implementation. Here, we experimentally investigate the thermal conductivity of orthorhombic polar LaWN₃, synthesized by high-pressure high-temperature technique. The observed thermal conductivity exhibits drastic reduction with decreasing temperature, reminiscent of the behavior in amorphous silica. We postulate the anomalous glass-like thermal conductivity to a synergistic interplay of potential Ferron–phonon interactions, lattice disorders from octahedral distortions, and wave-like atomic tunneling. This study represents a pioneering exploration of thermal transport within nitride perovskites, paving the way for future advancements in nitride-based electronics.

We study the thermal transport through a quantum spin-$\frac{1}{2}$ heterojunction, which consists of a finite-size chain with two-site anisotropic XY interaction and three-site XZX+YZY interaction coupled at its ends to two semi-infinite isotropic XY chains. By performing the Jordan–Wigner transformation, the original spin Hamiltonian is mapped onto a fermionic Hamiltonian. Then, the fermionic structure is discussed, and the heat current as a function of structural parameters is evaluated. It is found that the magnetic fields applied at respective chains play different roles in adjusting the heat current in this heterojunction. Moreover, the interplay between the anisotropy of the XY interaction and the three-site spin interaction assists to further control the thermal transport. In view of the numerical results, we propose this heterojunction to be an alternate candidate for manipulating the heat current in one-dimensional (1D) systems.

Skyrmions are topological solitons that emerge in many physical contexts. In magnetism, they appear as textures of the spin-density field stabilized by different competing interactions and characterized by a topological charge that counts the number of times the order parameter wraps the sphere. They behave as classical objects when the spin texture varies slowly on the scale of the microscopic lattice of the magnet. However, the fast development of experimental tools to create and stabilize skyrmions in thin magnetic films has led to a rich variety of textures, sometimes of atomistic sizes. In this paper, we discuss, in a pedagogical manner, how to introduce quantum interference in the translational dynamics of skyrmion textures, starting from the micromagnetic equations of motion for a classical soliton. We study how the nontrivial topology of the spin texture manifests in the semiclassical regime, when the microscopic lattice potential is treated quantum-mechanically, but the external driving forces are taken as smooth classical perturbations. We highlight close relations to the fields of noncommutative quantum mechanics, Chern–Simons theories, and the quantum Hall effect.

This study is conducted to discuss the thermal transport of second grade nanofluid flowing through a vertical channel. The nanoparticles, alumina (Al₂O₃), and titanium (TiO₂), are dispersed into the second grade base fluid to form a hybrid nanofluid. The governing equation prescribed model is constructed by applying the laws of conservation of mass and energy. It can be modified by converting the non-dimensional classical model to the fractional derivative model using Fick’s and Fourier’s laws. With the help of the Laplace transforms, the resulting dimensionless form of the governing equations and the closed form relations of temperature, concentration, and velocity are obtained. The physical behavior of the obtained result is judged graphically. The nanoparticle’s volume percentage increases the concentration and temperature distribution, but it has the opposite impact on the velocity profile.

The primary purpose of this study is to provide more information on the stable and incompressible stream of a hybrid nanofluid over a poignant tiny needle in two dimensions under slip boundary conditions. In the hybrid nanofluid flow, Al₂O₃ and Fe₃O₄ are nanoparticles, water and ethylene glycol (50:50) are considered as the base fluids. Furthermore, the impacts of Joule heating and inclined magnetic fields are considered. The PDE’s governing equations are converted into ODEs by using similarity transformations and solved by a numerical technique based on Runge–Kutta fourth-order method. The results illustrate that the crucial parameters such as the magnetic parameter, Eckert number, nanoparticles of solid volume fractions, inclined angle parameter, and Prandtl numbers significantly affect the momentum and thermal profiles. The heat transfer rate and skin friction factors are used to calculate the numerical values of various parameters, which are displayed in a table. These analyses manifest that raising the magnetic parameter results in a decrease in the hybrid nanofluid velocity under slip and no-slip circumstances. The Nusselt number has also grown as a result of the volumetric fractions of nanoparticles and the intensification of the angle parameter. This analysis might include areas such as microfluidics, biomedical devices, heat exchangers, and other engineering applications where precise control over fluid behavior and temperature distribution is important.

This paper presents a review on our recent work on carbon nanotube field effect transistors, including the development of ohmic contacts, high-κ gate dielectric integration, chemical functionalization for conformal dielectric deposition and pushing the performance limit of nanotube FETs by channel length scaling. Due to the importance of high current operations of electronic devices, we also review the high field electrical transport properties of nanotubes on substrates and in freely suspended forms. Owing to their unique properties originating from their crystalline 1D structure and the strong covalent carbon–carbon bonding configuration, carbon nanotubes are highly promising as building blocks for future electronics. They are found to perform favorably in terms of ON-state current density as compared to the existing silicon technology, owing to their superb electron transport properties and compatibility with high-κ gate dielectrics. Future directions and challenges for carbon nanotube-based electronics are also discussed.

We studied the thermal rectification effect in one-dimensional chains using the non-equilibrium Green's function method. Thermal rectification effect is observed in the presence of structure asymmetry and nonlinear interactions. We found that phonons with higher frequencies play a major role in thermal rectification. By controlling the phonon frequency band in the junction region, we are able to obtain rectification rate up to four percent. The results are comparable to experiment, and provide a clear interpretation of the physical processes involved.