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We study within the framework of the Lifshitz theory the long-range Casimir force for in-plane isotropic and anisotropic free-standing transdimensional material slabs. 

First principles simulations are utilized to calculate the electronic and vibrational properties of several metastable structural phases of the CuZn 2 InSe 4 quaternary chalcogenide, including stanite, kesterite, primitive mixed CuAu, wurtzite-stanite, and wurtzite-kesterite lattices. We find that although each phase is formed by nearest cation-chalcogen bonds, the structural diversity due to cation and polyhedral arrangements has direct consequences in the electronic structure. The simulations further indicate that hybrid functionals are needed to account for the s–p and p–d orbital hybridization that is found around the Fermi level, which leads to much enhanced energy band gaps when compared with standard exchange-correlation approaches. We also find that the thermal conductivities for all phases are relatively low, and the main scattering channel comes from a low frequency optical band hybridized with acoustic phonons. Given that CuZn 2 InSe 4 is a material from a larger class of quaternary chalcogenides, other materials may exhibit similar electronic and vibrational properties, which may be useful for electronic and thermal management applications. 

Abstract Thermoelectric (TE) transport in anisotropic materials is investigated based on most general thermodynamical concepts. Currents and power conversion efficiency are studied in SnSe and SnS in different directions. The design of composites whose TE performance along different principles directions is the same is proposed. Although such features do not occur naturally, such man-made anisotropic materials can be constructed using bilayers achieving much broadened working conditions of TE conversion devices. Intricate relationships between the anisotropy and the direction of the electric and heat currents are revealed, which further help us understand how transport occurs in such composites. 

The magnetic proximity effect (MPE) has recently been explored to manipulate interfacial properties of two-dimensional (2D) transition metal dichalcogenide (TMD)/ferromagnet heterostructures for use in spintronics and valleytronics. However, a full understanding of the MPE and its temperature and magnetic field evolution in these systems is lacking. In this study, the MPE has been probed in Pt/WS2/BPIO (biphase iron oxide, Fe3O4 and α-Fe2O3) heterostructures through a comprehensive investigation of their magnetic and transport properties using magnetometry, four-probe resistivity, and anomalous Hall effect (AHE) measurements. Density functional theory (DFT) calculations are performed to complement the experimental findings. We found that the presence of monolayer WS2 flakes reduces the magnetization of BPIO and hence the total magnetization of Pt/WS2/BPIO at T > ~120 K—the Verwey transition temperature of Fe3O4 (TV). However, an enhanced magnetization is achieved at T < TV. In the latter case, a comparative analysis of the transport properties of Pt/WS2/BPIO and Pt/BPIO from AHE measurements reveals ferromagnetic coupling at the WS2/BPIO interface. Our study forms the foundation for understanding MPE-mediated interfacial properties and paves a new pathway for designing 2D TMD/magnet heterostructures for applications in spintronics, opto-spincaloritronics, and valleytronics.