相关论文: Measurement of the variable surface charge concent…
We present first-principles calculations of the interface between GaN and strained AlN, using a slab model in which polarization is compensated via surface fractional-charge pseudo-hydrogen atoms. We show that an interface two-dimensional…
Van der Waals heterostructures have emerged as a versatile platform to study correlated and topological electron physics. Spectroscopy experiments in the THz regime are crucial, since the energy of THz photons matches that of relevant…
Understanding defects in atomically thin van der Waals (vdW) semiconductors is essential for advancing their use in next-generation optoelectronic and photovoltaic devices. Here, we apply a combination of various impedance spectroscopy…
Van der Waals structures formed by aligning monolayer graphene with insulating layers of hexagonal boron nitride exhibit a moir\'e superlattice that is expected to break sublattice symmetry. Despite an energy gap of several tens of…
Recently the graphene/SiC interface has emerged as a versatile platform for the epitaxy of otherwise unstable, monoelemental, two-dimensional (2D) layers via intercalation. Intrinsically capped into a van der Waals heterostructure with…
The semiconducting behaviour and optoelectronic response of gallium nitride is governed by point defect processes, which, despite many years of research, remain poorly understood. The key difficulty in the description of the dominant…
Stability and electronic properties of atomic layers of GaN are investigated in the framework of the van der Waals-density functional theory. We find that the ground state of the layered GaN is a planar graphene-like configuration rather…
GaN based high electron mobility transistors show promise in numerous device applications which elicits the need for accurate models of bulk, surface, and interface electronic properties. We detail here a hybrid density functional theory…
Molecular-scale manipulation of electronic/ionic charge accumulation in materials is a preeminent challenge, particularly in electrochemical energy storage. Layered van der Waals (vdW) crystals exemplify a diverse family of materials that…
In this paper we study the electrostatic interaction of a heterogeneously charged wall with a neutral semipermeable membrane. The wall consists of periodic stripes, where the charge density varies in one direction. The membrane is in a…
Over the last decade, progress in wide bandgap, III-V materials systems based on gallium nitride (GaN) has been a major driver in the realization of high power and high frequency electronic devices. Since the highly conductive,…
We report on our investigation of the electrical properties of metal/Al2O3/GaN metal-insulator-semiconductor (MIS) capacitors. We determined the conduction band offset and interface charge density of the alumina/GaN interface by analyzing…
We have addressed the existing ambiguity regarding the effect of process-induced strain in the underlying GaN layer on AlGaN/GaN heterostructure properties. The bandgaps and offsets for AlGaN on strained GaN are first computed using a cubic…
Surface reconstruction plays a vital role in determining the surface electronic structure and chemistry of semiconductors and metal oxides. However, it has been commonly believed that surface reconstruction does not occur in van der Waals…
Studies of the structural, electronic, and optical characteristics of the interfaces between graphene and ZnO polar surfaces is carried out using first-principles simulations. At the interface, a strong van der Waals force is present, and…
III-nitride wide bandgap semiconductors exhibit large exciton binding energies, preserving strong excitonic effects at room temperature. On the other hand, semiconducting two-dimensional (2D) materials, including MoS$_2$, also exhibit…
Trapping of charge at surface states is a longstanding problem in GaN that hinders a full realization of its potential as a semiconductor for microelectronics. At least part of this charge originates in molecules adsorbed on the GaN…
We investigate electron and ion surface states of a negatively charged dust particle in a gas discharge and identify the charge of the particle with the electron surface density bound in the polarization-induced short-range part of the…
The interaction between an electric field and the electric charges in a material is described by electrostatic screening, which in metallic systems is commonly thought to be confined within a distance of the order of the Thomas-Fermi…
We present a universal approach for determining the spontaneous polarization Psp of a wurtzite semiconductor from the emission energies of excitons bound to the different types of stacking faults in these crystals. Employing…