Related papers: Asymmetric double quantum dots as a subminiature m…
Parasitic two-level tunneling systems originating from structural material defects affect the functionality of various microfabricated devices by acting as a source of noise. In particular, superconducting quantum bits may be sensitive to…
A theoretical study on electrical current fluctuations in a double quantum dot connected to electronic reservoirs is presented, with the aim of deriving the finite-frequency noise, the Fano factor and the $\Delta T$-noise. We establish a…
We show that, in a system with defects, two-particle states may experience destructive quantum interference, or antiresonance. It prevents an excitation localized on a defect from decaying even where the decay is allowed by energy…
Recent advances in nanotechnology have enabled researchers to manipulate small collections of quantum mechanical objects with unprecedented accuracy. In semiconductor quantum dot qubits, this manipulation requires controlling the dot…
We present a theory of conductance and noise in generic mesoscopic conductors connected in parallel, and we demonstrate that the additivity of conductance and of shot noise arises as a sole property of the junctions connecting the two (or…
A theoretical prediction published in Phys.Rev. B 64, 012505 (2001) is corroborated experimentally. This corroboration of the theoretical result published in Physical Review B was rejected for publication in the same journal. Such…
Quantum dots are nanometer-scale semiconductor particles that exhibit size-dependent quantum mechanical properties. In this work, we investigate the dynamics of quantum correlations, quantified by the concurrence and the quantum coherence,…
We show that a superconducting circuit containing two loops, when treated with Macroscopic Quantum Coherence (MQC) theory, constitutes a complete two-bit quantum computer. The manipulation of the system is easily implemented with…
We present a semiclassical analysis of the instability of an electron shuttle composed of three quantum dots: two are fixed and coupled via leads to electron resevoirs at different chemical potentials, while the central dot is mounted on a…
A mesoscopic oscillator in U-shape has been proposed and studied. Making use of a magnetic flux together with a potential of confinement, the electron contained in the oscillator has been localized initially and an amount of energy has been…
Electrical engineers and physicists are naturally very interested in noise in circuits, amplifiers and detectors. With the advent of quantum computation and other high frequency electronics operating at low temperatures, we have entered a…
The noise properties of pump currents through an open double quantum dot setup with non-adiabatic ac driving are investigated. Driving frequencies close to the internal resonances of the double dot-system mark the optimal working points at…
The dynamics of a quantum anharmonic oscillator whose position is monitored by a Bose-Einstein condensate (BEC) trapped in a symmetric double well potential is studied. The (non-exponential) decoherence induced on the oscillator by the…
Though electrical noise and conduction current are assigned to corpuscle-like electrons drifting in solid matter, this model hardly fits in the Fluctuation-Dissipation framework. However, fluctuations of energy due to displacements of…
Owing to a few unique advantages, double-dot single electron transistor has been proposed as an alternative detector for charge states. In this work, we present a further study for its signal-to-noise property, based on a full analysis of…
A new phenomenon is observed experimentally in a heavily doped asymmetric quantum-size structure in a magnetic field parallel to the quantum-well layers - a transverse magnetoresistance which is asymmetric in the field (there can even be a…
The low-frequency shot-noise power of a normal-metal-superconductor junction is studied for arbitrary normal region. Through a scattering approach, a formula is derived which expresses the shot-noise power in terms of the transmission…
A quantum computer based on an asymmetric coupled dot system has been proposed and shown to operate as the controlled-NOT-gate. The basic idea is (1) the electron is localized in one of the asymmetric coupled dots. (2)The electron transfer…
A brief review of the supersymmetry method and its application to mesoscopic physics and quantum chaos is given. Alghough a non-linear supermatrix $% \sigma $-model in this approach was derived from models with random potential, it is…
The noise in physical qubits is fundamentally asymmetric: in most devices, phase errors are much more probable than bit flips. We propose a quantum error correcting code which takes advantage of this asymmetry and shows good performance at…