Related papers: Strong interlayer charge transfer due to exciton c…
Hybrid systems represent one of the frontiers in the study of unconventional superconductivity and are a promising platform to realize topological superconducting states. Owing to their mesoscopic dimensions, these materials are challenging…
We present measurements of Coulomb drag in an ambipolar GaAs/AlGaAs double quantum well structure that can be configured as both an electron-hole bilayer and a hole-hole bilayer, with an insulating barrier of only 10 nm between the two…
Tunneling spectroscopy reveals evidence for interlayer electron-hole correlations in quantum Hall bilayer two-dimensional electron systems at layer separations near, but above, the transition to the incompressible exciton condensate at…
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…
XY* transitions represent one of the simplest examples of unconventional quantum criticality, in which fractionally charged excitations condense into a superfluid, and display novel features that combine quantum criticality and…
We consider various exchange-driven electronic instabilities in semiconductor double-layer systems in the absence of any external magnetic field. We establish that there is no exchange-driven bilayer to monolayer charge transfer instability…
We investigate charge transport through the junction between a niobium superconductor and the edge of a two-dimensional electron-hole bilayer, realized in an InAs/GaSb double quantum well. For the transparent interface with a…
A recent Letter by Zhu et al [Phys. Rev. Lett. 127, 247702 (2021)] claimed a unified mechanism for quantum oscillations (QOs) in graphite-gated 2D devices based on studies of three cases (WTe2, MoTe$_2$/WSe$_2$ heterobilayers and bilayer…
We present transport measurements through an electrostatically defined bilayer graphene double quantum dot in the single electron regime. With the help of a back gate, two split gates and two finger gates we are able to control the number…
Two-dimensional (2D) device structures have recently attracted considerable attention. Here, we show that most 2D device structures, regardless vertical or lateral, act as a lateral monolayer-bilayer-monolayer junction in their operation.…
We study the influence of quantizing perpendicular magnetic fields on the ground state of a bilayer with electron and hole fluids separated by an opaque tunnel barrier. In the absence of a field, the ground state at low carrier densities is…
We have investigated the tunneling properties of an electron double quantum well system where the lowest Landau level of each quantum well is half filled. This system is expected to be a Bose condensate of excitons. Our four-terminal dc…
Quantum well (QW) structures are widely used in lasers, semiconductor optical amplifiers, modulators, enabling their monolithic integration on the same substrate. As optoelectronic systems evolve to meet the growing bandwidth demands in the…
A microscopic model of a heterostructure with a quantum well (QW) is proposed to study the exciton behavior in an external electric field. The effect of an electric field ranging from 0 to 6 kV/cm applied to the GaAs/AlGaAs QW structure in…
We present a theory of bilayer two-dimensional electron systems that host a spatially indirect exciton condensate when in thermal equilibrium. Equilibrium bilayer exciton condensates (BXCs) are expected to form when two nearby semiconductor…
The bilayer systems exhibit the Bose-Einstein condensation of excitons that emerge due to Coulomb pairing of electrons belonging to one layer with the holes belonging to the other layer. Here we present the microscopic derivation of the…
We present a controlled mechanical exfoliation technique for bulk 3D topological insulators that yields atomically clean ultrathin flakes, enabling quantum well states (QWS) of Dirac electrons to be clearly resolved. Achieving reliable…
Quantum spin Hall insulators, recently realized in HgTe/(Hg,Cd)Te quantum wells, support topologically protected, linearly dispersing edge states with spin-momentum locking. A local magnetic exchange field can open a gap for the edge…
Quantum wells constitute one of the most important classes of devices in the study of 2D systems. In a double layer QW, the additional "which-layer" degree of freedom gives rise to celebrated phenomena such as Coulomb drag, Hall drag and…
We investigate the quasiparticle excitation of the bilayer quantum Hall (QH) system at total filling factor $\nu_{\mathrm{T}} = 1$ in the limit of negligible interlayer tunneling under tilted magnetic field. We show that the intrinsic…