Related papers: Charge State Hysteresis in Semiconductor Quantum D…
The states of two electrons in tunnel-coupled semiconductor quantum dots can be effectively described in terms of a two-spin Hamiltonian with an isotropic Heisenberg interaction. A similar description needs to be generalized in the case of…
We report charge detection studies of a lateral double quantum dot with controllable charge states and tunable tunnel coupling. Using an integrated electrometer, we characterize the equilibrium state of a single electron trapped in the…
We report charge detection in degenerately phosphorus-doped silicon double quantum dots (DQD) electrically connected to an electron reservoir. The sensing device is a single electron transistor (SET) patterned in close proximity to the DQD.…
It is shown that the noise-limited charge sensitivity of a single-electron transistor using superconductors (of either $SISIS$ or $NISIN$ type) operating near the threshold of quasiparticle tunneling, can be considerably higher than that of…
We study theoretically the quantum dynamics of an electron in the singly-ionized double-donor structure in the semiconductor host under the influence of two strongly detuned laser pulses. This structure can be used as a charge qubit where…
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…
We present a theory of electronic properties and the spin blockade phenomena in a gated linear triple quantum dot. Quadruple points where four different charge configurations are on resonance, particularly involving (1,1,1) configuration,…
We perform quantum Hall measurements on three types of commercially available modulation doped Si/SiGe heterostructures to determine their suitability for depletion gate defined quantum dot devices. By adjusting the growth parameters, we…
Achieving controllable coupling of dopants in silicon is crucial for operating donor-based qubit devices, but it is difficult because of the small size of donor-bound electron wavefunctions. Here we report the characterization of a quantum…
Memristors are resistive elements retaining information of their past dynamics. They have garnered substantial interest due to their potential for representing a paradigm change in electronics, information processing and unconventional…
We report on the realization of a single-electron source, where current is transported through a single-level quantum dot (Q), tunnel-coupled to two superconducting leads (S). When driven with an ac gate voltage, the experiment demonstrates…
We report electrical transport measurements through a semiconducting single-walled carbon nanotube (SWNT) with three additional top-gates. At low temperatures the system acts as a double quantum dot with large inter-dot tunnel coupling…
It is shown that superconducting charge and phase qubits are quantum versions of memory capacitive and inductive systems, respectively. We demonstrate that such quantum memcapacitive and meminductive devices offer remarkable and rich…
We report on single-electron shuttling experiments with a silicon metal-oxide-semiconductor quantum dot at 300 mK. Our system consists of an accumulated electron layer at the Si/SiO_2 interface below an aluminum top gate with two additional…
There has been a recent surge of interest in understanding charge transport at atomic scales. The motivations are myriad, including understanding the conductance properties of peptides measured experimentally. In this study, we propose a…
Charge noise in semiconducting quantum dots has been observed to have a 1/f spectrum. We propose a model in which a pair of quantum dots are coupled to a 2D bath of fluctuating two level systems (TLS) that have electric dipole moments and…
Quantum dots are artificial atoms used for a multitude of purposes. Charge defects are commonly present and can significantly perturb the designed energy spectrum and purpose of the dots. Voltage controlled exchange energy in silicon double…
We show how two qubits encoded in the orbital states of two quantum dots can be entangled or disentangled in a controlled way through their interaction with a weak electron current. The transmission/reflection spectrum of each scattered…
Hole spins in Ge/SiGe heterostructure quantum dots have emerged as promising qubits for quantum computation. The strong spin-orbit coupling (SOC), characteristic of heavy-hole states in Ge, enables fast and all-electrical qubit control.…
The nonlinear conductance of semiconductor heterostructures and single molecule devices exhibiting Kondo physics has recently attracted attention. We address the observed sample dependence of the measured steady state transport coefficients…