Vo Van Tai , Truong Van Tuan , Tran Trong Tai , Le Tri Dat , Nguyen Duy Vy
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引用次数: 0
Abstract
We theoretically study the thermoelectric transport in a double-layer bilayer graphene (BLG-GaAs-BLG) system on dielectric substrates (h-BN, AlO, HfO). Electrons interact with GaAs acoustic phonons via both the deformation potential (acDP) and piezoelectric (acPE) scattering. Results show that piezoelectric scattering dominates the total transport, especially at low carrier density and high dielectric constant. Substrate dielectric constant significantly influences thermopower , and the thermopower of the materials is in the order of HfO AlO h-BN. When densities on two BLG layers are unequal, the contribution from acDP scattering decreases (increases) at low (high) densities versus equal densities, while acPE scattering remains stable, making largely -dependent. Increasing interlayer distance enhances , while higher temperature boosts (notably at low densities) with minimal effect on . These insights and substrate-dependent trends demonstrate substrate engineering as a key parameter for optimizing BLG thermoelectric devices.
期刊介绍:
Physica E: Low-dimensional systems and nanostructures contains papers and invited review articles on the fundamental and applied aspects of physics in low-dimensional electron systems, in semiconductor heterostructures, oxide interfaces, quantum wells and superlattices, quantum wires and dots, novel quantum states of matter such as topological insulators, and Weyl semimetals.
Both theoretical and experimental contributions are invited. Topics suitable for publication in this journal include spin related phenomena, optical and transport properties, many-body effects, integer and fractional quantum Hall effects, quantum spin Hall effect, single electron effects and devices, Majorana fermions, and other novel phenomena.
Keywords:
• topological insulators/superconductors, majorana fermions, Wyel semimetals;
• quantum and neuromorphic computing/quantum information physics and devices based on low dimensional systems;
• layered superconductivity, low dimensional systems with superconducting proximity effect;
• 2D materials such as transition metal dichalcogenides;
• oxide heterostructures including ZnO, SrTiO3 etc;
• carbon nanostructures (graphene, carbon nanotubes, diamond NV center, etc.)
• quantum wells and superlattices;
• quantum Hall effect, quantum spin Hall effect, quantum anomalous Hall effect;
• optical- and phonons-related phenomena;
• magnetic-semiconductor structures;
• charge/spin-, magnon-, skyrmion-, Cooper pair- and majorana fermion- transport and tunneling;
• ultra-fast nonlinear optical phenomena;
• novel devices and applications (such as high performance sensor, solar cell, etc);
• novel growth and fabrication techniques for nanostructures