Related papers: Bi-stable tunneling current through a molecular qu…
We discover that quantum dynamical tunneling, occurring between phase space regions in a classically forbidden way, can break conserved quantities in pseudointegrable systems. We rigorously prove that a conserved quantity in a class of…
We show that the energy splitting between the bonding and antibonding molecular states of holes in vertically stacked quantum dots can be tuned using longitudinal magnetic fields. With increasing field, the energy splitting first decreases…
Magnetotunneling spectroscopy was employed to probe the confinement in vertical Si/Ge double-barrier resonant tunneling diodes with regularly distributed Ge quantum dots. Their current-voltage characteristics reveal a step-like behavior in…
We investigate quantum tunneling in the theory of a complex scalar field with a global $U(1)$ symmetry when the charge density of the initial configuration does not vanish. We discuss the possible final configurations and set up the…
A quantum dot weakly coupled to two normal metal leads exhibits resonant transmission when one of the dot energy levels lies within the applied bias window. But when the quantum dot is sidecoupled to the transport channel, transmission in…
We investigate quantum photovoltaic effect in double quantum dots by applying nonequilibrium quantum master equation. The drastic suppression of the photovoltaic current is observed near the open circuit voltage, which leads to the large…
Recently observed Aharonov-Bohm quantum interference of period h/2e in charge density wave rings strongly suggest that correlated density wave electron transport is a cooperative quantum phenomenon. The picture discussed here posits that…
A gate electric field has a small but non-negligible effect on the phase of the valley-orbit coupling in Si quantum dots. Finite interdot tunneling between valley eigenstates in a double quantum dot is enabled by a small difference in the…
We fabricated a quantum dot coupled laterally to a two-dimensional electron gas and vertically to a three-dimensional electron gas in order to investigate the eigenstate dependence of tunneling rate to these gases. We observed a…
In Coulomb drag, a current flowing in one conductor can induce a voltage across an adjacent conductor via the Coulomb interaction. The mechanisms yielding drag effects are not always understood, even though drag effects are sufficiently…
The quasi-energy spectrum recently measured in experiments with a squeeze-driven superconducting Kerr oscillator showed good agreement with the energy spectrum of its corresponding static effective Hamiltonian. The experiments also…
We present results of molecular dynamics simulations for two-dimensional repulsively interacting colloids driven by a one dimensional asymmetric and commensurate ratchet potential, switching on and off stochastically. This drives a…
Quantum tunneling from a thin wire or a thin film through a static potential barrier in a zero magnetic field is studied. The wire or the film should satisfy a condition of transverse quantization of levels and be inhomogeneous. Depending…
We analyze a quantum spin Hall (QSH) device with a point contact connecting two of its edges. The contact supports a net spin tunneling current that can be probed experimentally via a two-terminal resistance measurement. We find that the…
Two-dimensional superconductors offer an excellent platform for the study of vortex matter due to their low superfluid stiffness and inability to effectively screen applied magnetic fields. Here we explore vortices in a two-dimensional…
We calculate non-perturbatively the inelastic effects on the conductance through a conjugated molecular wire-metal heterojunction, including realistic electron-phonon coupling. We show that at sub-band-gap energies the current is dominated…
The possibility of using single molecule junctions as electron pumps for energy conversion and storage is considered. It is argued that the small dimensions of these systems enable to make use of unique intra-molecular quantum coherences in…
We report on a quantum dot device design that combines the low disorder properties of undoped SiGe heterostructure materials with an overlapping gate stack in which each electrostatic gate has a dominant and unique function -- control of…
We present measurements of transport through two tunnel-coupled quantum dots of different sizes connected in series in a strong, variable, perpendicular magnetic field. Double dot conductance was measured both as a function of magnetic…
We investigate the transport of electrons through a double-barrier resonant-tunneling structure in the regime where the current-voltage characteristics exhibit bistability. In this regime one of the states is metastable, and the system…