Related papers: Dipole-Allowed Direct Band Gap Silicon Superlattic…
We present the first observations of zero-n bandgaps in photonic crystal superlattices consisting of alternating stacks of negative index photonic crystals and positive index dielectric materials in the near-infrared. Guided by ab initio…
A topological insulator possesses a bulk energy gap splitting the lowest empty band from the highest occupied electronic band. The electronic states at the surface (or edge in two dimensions), on the other hand, of a topological insulator…
Before assessing the suitability of a semiconductor for specific applications, the first question to ask is whether it possesses a direct or indirect band gap. This distinction is fundamental, as the operation of devices such as…
Two-dimensional atomic crystals can radically change their properties in response to external influences such as substrate orientation or strain, resulting in essentially new materials in terms of the electronic structure. A striking…
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, unconventional superconductivity having a zero-bias conductance peak is reported in doped topological Dirac semimetal (DSM) with lattice distortion. Motivated by the experiments, we theoretically study the possible…
We present a combined experimental and theoretical analysis of the evolution of the near-band gap electronic and optical properties of Si$_{x}$Ge$_{1-x-y}$Sn$_{y}$ alloys lattice-matched to Ge and GaAs substrates. We perform…
Employing density functional theory based calculations, we investigate structural, vibrational and strain-dependent electronic properties of an ultra-thin CdTe crystal structure that can be de- rived from its bulk counterpart. It is found…
Geometry, whether on the atomic or nanoscale, is a key factor for the electronic band structure of materials. Some specific geometries give rise to novel and potentially useful electronic bands. For example, a honeycomb lattice leads to…
The moir\'e superlattice of misaligned atomic bilayers paves the way for designing a new class of materials with wide tunability. In this work, we propose a photonic analog of the moir\'e superlattice based on dielectric resonator…
It is difficult to intuit how electronic structure features$-$such as band gap magnitude, location of band extrema, effective masses, etc.$-$arise from the underlying crystal chemistry of a material. Here we present a strategy to distill…
Epitaxial bilayer silicon oxide is a transferable two-dimensional material predicted to be a wide band gap semiconductor, with potential applications for deep UV optoelectronics, or as a building block of van der Waals heterostructures. The…
We investigate graphene superlattices of nitrogen and boron substitutional defects and by using symmetry arguments and electronic structure calculations we show how such superlattices can be used to modify graphene band structure.…
Bandgap engineering and quantum confinement in semiconductor heterostructures provide the means to fine-tune material response to electromagnetic fields and light in a wide range of the spectrum. Nonetheless, forming semiconductor…
Based on first-principles calculations we showed that superlattices of periodically repeated junctions of hydrogen saturated silicon nanowire segments having different lengths and diameters form multiple quantum well structures. The band…
Superlattice engineering in van der Waals heterostructures (e.\,g.\ by moir\'e engineering) provides a powerful platform for designing electronic bands and realising correlated and topological quantum phenomena. Here, we pioneer a scheme to…
Lateral superlattices have attracted major interest as this may allow one to modify spectra of two dimensional electron systems and, ultimately, create materials with tailored electronic properties. Previously, it proved difficult to…
According to the Bardeen-Cooper-Schrieffer (BCS) theory, superconductivity usually needs well defined Fermi surface(s) with strong electron-phonon coupling and moderate quasiparticle density of states (DOS). A kagome lattice can host flat…
Silicon can be heavily doped with phosphorus in a single atomic layer (a $\delta$ layer), significantly altering the electronic structure of the conduction bands within the material. Recent progress has also made it possible to further dope…
The remarkable properties of graphene stem from its two-dimensional (2D) structure, with a linear dispersion of the electronic states at the corners of the Brillouin zone (BZ) forming a Dirac cone. Since then, other 2D materials have been…