The isolation of the two-dimensional semiconductor molybdenum disulphide introduced a new optically active material possessing a band gap that can be facilely tuned via elastic strain. As an atomically thin membrane with exceptional strength, monolayer molybdenum disulphide subjected to biaxial strain can embed wide band gap variations overlapping the visible light spectrum, with calculations s...

The combination of semiconductor quantum well structures and strongly piezoelectric crystals leads to a system in which surface acoustic waves with very large amplitudes can interact with charge carriers in the well. The surface acoustic wave induces a dynamic lateral superlattice potential in the plane of the quantum well which is strong enough to spatially break up a two-dimensional electron ...

We demonstrate optical switching of electrically resonant terahertz planar metamaterials fabricated on ErAs/GaAs nanoisland superlattice substrates. Photoexcited charge carriers in the superlattice shunt the capacitive regions of the constituent elements, thereby modulating the resonant response of the metamaterials. A switching recovery time of 20 ps results from fast carrier recombination in ...

In this study, we made the heterojunction solar cells on Si substrate by fabricating a nanocrystalline Si/SiO2 superlattice emitter structure. Amorphous silicon and silicon dioxide superlattice were prepared by rf Si sputtering and plasma oxidation, respectively. The deposited amorphous silicon was crystallized at high temperature. Microstructure studies by TEM show that amorphous silicon was c...

While Fabry-Pérot (FP) resonances and Moiré superlattices are intensively studied in graphene on hexagonal boron nitride (hBN), the two effects have not been discussed in their coexistence. Here we investigate the FP oscillations in a ballistic pnp-junctions in the presence and absence of a Moiré superlattice. First, we address the effect of the smoothness of the confining potential on the visi...

Alkyl chains dynamics in monolayer protected metal cluster (MPC) systems of gold and silver have been studied by the quasielastic neutron scattering (QENS) technique. Isolated MPCs investigated are 6, 12 and 18 carbon n-alkyl chain thiolate protected 4 nm diameter gold clusters while the superlattices are their silver analogues. Evolution of dynamics with temperature is found to be very differe...

Heat conduction of single-walled carbon nanotubes (SWNTs) isotope-superlattice is investigated by means of classical molecular dynamics simulations. Superlattice structures were formed by alternately connecting SWNTs with different masses. On varying the superlattice period, the critical value with minimum effective thermal conductivity was identified, where dominant physics switches from zone-...

Improvement of ferroelectric property by LaNiO3 (LNO) electrode on superlattice films was shown in this study. High quality asymmetric multiferroic 5 at% La-doped BiFeO3 (BFO) and paraelectric SrTiO3 confirmed by clear main feature and satellite features around (0 0 2) STO substrate Bragg peak shown in (0 0 2) radial scan spectrum. The results of in-pane crystal truncation rod (CTR) spectrum an...

We have developed a general X-ray diffraction model which enables to investigate interfacial disorder in crystalline/amorphous and crystalline/ crystalline multilayers. Using classical structure factor calculations, we simulate the evolution of the diffracted X-ray intensities as a function of the fluctuation amplitude, the superlattice wavelength and the interatomic distances. From experimenta...

Weakly coupled semiconductor superlattices under dc voltage bias are excitable systems with many degrees of freedom that may exhibit spontaneous chaos at room temperature and act as fast physical random number generator devices. Superlattices identical periods current self-oscillations due to the dynamics charge dipole waves but chaotic oscillations exist on narrow intervals. They disappear eas...