Related papers: Error detection in a tunable-barrier electron pump
Nanostructures defined in high-mobility two-dimensional electron systems offer a unique way of controlling the microscopic details of the investigated device. Quantum point contacts play a key role in these investigations, since they are…
Quantum detector properties of the quantum point contact (QPC) are analyzed for arbitrary electron transparency and coupling strength to the measured system and are shown to be determined by the electron counting statistics. Conditions of…
We report a theoretical analysis of parametric electron pump through a quantum dot in the Kondo regime. In the adiabatic regime, we have derived the expression for pumped current in the Kondo regime using non-equilibrium Green's function.…
We propose a quantum charging scheme fueled by measurements on ancillary qubits serving as disposable chargers. A stream of identical qubits are sequentially coupled to a quantum battery of $N+1$ levels and measured by projective operations…
We report electronic control and measurement of an imbalance between spin-up and spin-down electrons in micron-scale open quantum dots. Spin injection and detection was achieved with quantum point contacts tuned to have spin-selective…
Quasi-static transport measurements are employed to characterize a few electron quantum dot electrostatically defined in a GaAs/AlGaAs heterostructure. The gate geometry allows observations on one and the same electron droplet within a wide…
We present finite bias measurements on a quantum dot coupled capacitively to a quantum point contact used as a charge detector. The transconductance signal measured in the quantum point contact at finite dot bias shows structure which…
We obtain the finite-temperature unconditional master equation of the density matrix for two coupled quantum dots (CQD) when one dot is subjected to a measurement of its electron occupation number using a point contact (PC). To determine…
Compressibility measurements, sensitive to charge rearrangements, are performed on a quantum point contact (QPC). Screening due to mobile charges in the QPC is quantitatively measured, using a second point contact to detect the screened…
Recent demonstrations using electron spins stored in quantum dots array as qubits are promising for developing a scalable quantum computing platform. An ongoing effort is therefore aiming at the precise control of the quantum dots…
We address a foundational question in quantum mechanics: Can a particle be directly found in a classically forbidden virtual state? We instantiate this conceptual question by investigating the traversal of electrons through a tunnel…
We have measured the full counting statistics (FCS) of current fluctuations in a semiconductor quantum dot (QD) by real-time detection of single electron tunneling with a quantum point contact (QPC). This method gives direct access to the…
We study the effects of inter-electron interactions on the charge pumped through an adiabatic quantum electron pump. The pumping is through a system of barriers, whose heights are deformed adiabatically. (Weak) interaction effects are…
We study the dynamics of a single electron spin in a double quantum dot (DQD) and its readout via a quantum point contact (QPC). We model the system microscopically and derive rate equations for the reduced electron density matrix of the…
We investigate magneto-transport through a 1.6 \mu m wide quantum dot (QD) with adjacent charge detector, for different integer filling factors in the QD and constrictions. When this system is operated as a Fabry-P\'erot interferometer,…
The quantum efficiency, which characterizes the quality of information gain against information loss, is an important figure of merit for any realistic quantum detectors in the gradual process of collapsing the state being measured. In this…
The detection of the quantum dot charge state using a quantum point contact charge detector has opened a new exciting route for the investigation of quantum dot devices in recent years. In particular, time-resolved charge detection allowed…
Solid-state devices can be fabricated at the atomic scale, with applications ranging from classical logic to current standards and quantum technologies. While it is very desirable to probe these devices and the quantum states they host at…
We study the current noise through an unbiased quantum electron pump and its mesoscopic fluctuations for arbitrary temperatures and beyond the bilinear response. In the bilinear regime, we find the full distributions of the noise power and…
In this study, we address challenges in designing quantum information processors based on electron spin qubits in electrostatically-defined quantum dots (QDs). Numerical calculations of charge stability diagrams are presented for a…