Related papers: Counterflow of electrons in two isolated quantum p…
We briefly overview our recent results on nonequilibrium interactions between neighboring electrically isolated nanostructures. One of the nanostructures is represented by an externally biased quantum point contact (drive-QPC), which is…
We develop a master equation approach to study the backaction of quantum point contact (QPC) on a double quantum dot (DQD) at zero bias voltage. We reveal why electrons can pass through the zero-bias DQD only when the bias voltage across…
Quantum backflow is a counterintuitive effect in which the probability density of a free particle moves in the direction opposite to the particle's momentum. If the particle is electrically charged, then the effect can be viewed as the…
Electron charge transport through a quantum point contact (QPC) driven by an asymmetric spin bias is studied. A large charge current is induced when the transmission coefficient of the QPC jumps from one integer plateau to the next.…
We study a double quantum dot (DQD) coupled to a strongly biased quantum point contact (QPC), each embedded in independent electric circuits. For weak interdot tunnelling we observe a finite current flowing through the unbiased Coulomb…
We observe individual tunnel events of a single electron between a quantum dot and a reservoir, using a nearby quantum point contact (QPC) as a charge meter. The QPC is capacitively coupled to the dot, and the QPC conductance changes by…
Entanglement between particle and detector is known to be inherent in the measurement process. Gurvitz recently analyzed the coupling of an electron in a double dot (DD) to a quantum point contact (QPC) detector. In this paper we examine…
We consider two one-dimensional quantum $XX$ magnets linked by a periodically driven quantum point contact (QPC). If magnets are initially polarized in opposite directions, one expects that a spin current through the QPC will establish. It…
Quantum point contacts (QPCs) are commonly employed to capacitively detect the charge state of coupled quantum dots (QD). An indirect back-action of a biased QPC onto a double QD laterally defined in a GaAs/AlGaAs heterostructure is…
We measure the resistance oscillation of quantum point contact (QPC) under microwave (MW) radiation. What is different from the common resistance oscillation induced by edge magnetoplasmon (EMP) is that at lower magnetic field…
Small differential conductance oscillations as a function of source-drain bias were observed and systematically studied in an asymmetric quantum point contact (QPC). These oscillations become significantly suppressed in a small in-plane…
We use time-resolved charge detection techniques to investigate single-electron tunneling in semiconductor quantum dots. The ability to detect individual charges in real-time makes it possible to count electrons one-by-one as they pass…
Quantum Hall phases are gapped in the bulk but support chiral edge modes, both charged and neutral. Here we consider a circuit where the path from the source of electric current to the drain necessarily passes through a segment consisting…
We solve the master equations of two charged qubits measured by two serially coupled quantum point contacts (QPCs). We describe two-qubit dynamics by comparing entangled states with product states, and show that the QPC current can be used…
We study a voltage-driven quantum point contact (QPC) strongly coupled to a qubit. We predict pronounced observable features in the QPC current that can be interpreted in terms of half-integer charge transfers. Our analysis is based on the…
We study the dynamics of a charge qubit, consisting of a single electron in a double well potential, coupled to a point-contact (PC) electrometer using the quantum trajectories formalism. In contrast with previous work, our analysis is…
We study the phenomenon of quantum backflow in tight-binding systems with complex couplings, considering different boundary conditions and lattice sizes. Backflow is an intrinsically non-classical effect where the density flux associated…
The electron and current density distributions in the close proximity of quantum point contacts (QPCs) are investigated. A three dimensional Poisson equation is solved self-consistently to obtain the electron density and potential profile…
It was proposed that a double quantum dot can be used to be a detector of spin bias. Electron transport through a double quantum dot is investigated theoretically when a pure spin bias is applied on two conducting leads contacted to the…
When two superconductors become electrically connected by a weak link a zero-resistance supercurrent can flow. This supercurrent is carried by Cooper pairs of electrons with a combined charge of twice the elementary charge, e. The 2e charge…