Related papers: Electrically Controlled Two-Dimensional Electron-H…
We obtain the numerical ground state of a one-dimensional ladder model with the upper and lower chains occupied by spatially-separated electrons and holes, respectively. Under charge neutrality, we find that the excitonic bound states are…
We measure the frequency dependent capacitance of a gate covering the edge and part of a two-dimensional electron gas in the quantum Hall regime. In applying a positive gate bias, we create a metallic puddle under the gate surrounded by an…
Most self-assembled quantum dot molecules are intrinsically asymmetric with inequivalent dots resulting from imperfect control of crystal growth. We have grown vertically-aligned pairs of InAs/GaAs quantum dots by molecular beam epitaxy,…
Recently, Dial et al. presented measurements of the tunneling density of states into the bulk of a two dimensional electron gas under strong magnetic fields. Several high energy features appear in the measured spectrum showing a distinct…
A time-dependent electromagnetic field creates electron-hole excitations in a Fermi sea at low temperature. We show that the electron-hole pairs can be generated in a controlled way using harmonic and biharmonic time-dependent voltages…
Tellurium (Te) is a narrow bandgap semiconductor with a unique chiral crystal structure. The topological nature of electrons in the Te conduction band can be studied by realizing n-type doping using atomic layer deposition (ALD) technique…
The bound electron-hole pairs known as excitons govern the optical properties of insulating solids. While their behavior in equilibrium is well-understood theoretically, the nonequilibrium regime at high excitation densities-where phenomena…
We use interlayer tunneling to study bilayer 2D electron systems at $\nu_T = 1$ over a wide range of charge density imbalance, $\Delta \nu =\nu_1-\nu_2$, between the two layers. We find that the strongly enhanced tunneling associated with…
A theory of transport in the quantum Hall regime is developed for separately contacted double-layer electron systems. Inter-layer tunneling provides a channel for equilibration of the distribution functions in the two layers and influences…
Quasi-static transport measurements are employed on a laterally defined tunnel-coupled double quantum dot. A nearby quantum point contact allows us to track the charge as added to the device. If charged with only up to one electron, the…
In the last few years, interest in monomolecular layers of transition metal dichalcogenides (TMDs) has been driven by their unusual electronic and optical properties, which are very attractive for designing functional elements of new…
We study the properties of an electron on a catenoid surface. The catenoid is understood as a realization of a bridge connecting two graphene layer by a smooth surface. The curvature induces a symmetrical reflectionless potential well…
In high-quality solid-state systems at low temperatures, the hydrodynamic or the ballistic regimes of heat and charge transport are realized in the electron and the phonon systems. In these regimes, the thermal and the electric conductance…
Band-inverted electron-hole bilayers support quantum spin Hall insulator and exciton condensate phases. We investigate such a bilayer in an external magnetic field. We show that the interlayer correlations lead to formation of a helical…
Superfluidity has recently been reported in double electron-hole bilayer graphene. The multiband nature of the bilayers is important because of the very small band gaps between conduction and valence bands. The long range nature of the…
Band structure determines the motion of electrons in a solid, giving rise to exotic phenomena when properly engineered. Drawing an analogy between electrons and photons, artificially designed optical lattices indicate the possibility of a…
Excitonic insulators represent a unique quantum phase of matter, providing a rich ground for studying exotic quantum bosonic states. Strongly coupled electron-hole bilayers, which host stable dipolar exciton fluids with an exciton density…
Bilayer electron-hole systems, where carriers in one layer are electrons and carriers in the other are holes, have been actively investigated in recent years with the focus on Bose-Einstein condensation of excitons. This condensation is…
The condensation of excitons, bound electron-hole pairs in a solid, into a coherent collective electronic state was predicted over 50 years ago. Perhaps surprisingly, the phenomenon was first observed in a system consisting of two…
We report a combined analytic and Molecular Dynamics analysis of the collective mode spectrum of an electron-hole (bipolar) bilayer in the strong coupling quasi-classical limit. A robust, isotropic energy gap is identified in the…