相关论文: Noise at a Fermi-edge singularity

In the presence of spatial variation of the magnetization direction, electric current noise causes a fluctuating spin-transfer torque that increases the fluctuations of the ferromagnetic order parameter. By the fluctuation-dissipation…

Faraday rotation is one way to realize quantum non-demolition measurement of electron spin in quantum dots. To describe Faraday rotation, semiclassical models are typically used, based on quantized electron spin states and classical…

We review a number of recent experiments which are probing ground state and excitations of few-electron systems in self-assembled InAs quantum dots. Far-infrared spectroscopy, together with local as well as large-scale capacitive probing…

The performance of a quantum computation system is investigated, with qubits represented by magnetic impurities in coupled quantum dots filled with two electrons. Magnetic impurities are electrically manipulated by electrons. The dominant…

We calculate the electronic polarizability in the superconducting state near extremum vectors ${\vec Q}_0$ of the Fermi surface. A pole appears in the polarizability at frequencies $\omega$ near the superconducting gap $2\Delta$ which leads…

We study the Kondo effect in a quantum dot which is coupled to ferromagnetic leads and analyse its properties as a function of the spin polarization of the leads. Based on a scaling approach we predict that for parallel alignment of the…

An applied magnetic field affects a superconductor in two ways -- by promoting pairing fluctuations, and by inducing topological defects called vortices that carry quantized magnetic flux. A quantitative characterization of the resultant…

We study decoherence of an electron spin qubit in a quantum dot due to charge noise. We find that at the lowest order, the pure dephasing channel is suppressed for both $1/f$ charge noise and Johnson noise, so that charge noise leads to a…

Charge noise is one of the main sources of environmental decoherence for spin qubits in silicon, presenting a major obstacle in the path towards highly scalable and reproducible qubit fabrication. Here we demonstrate in-depth…

We investigate theoretically shot noise in an artificial Single Molecule Magnet based upon a CdTe quantum dot doped with a single S=5/2 Mn spin and gated in the hole sector. Mn-hole exchange anisotropy is shown to lead to profound…

We determine the shot noise asymmetry of a quantum dot under reversal of an external magnetic field. The dot is coupled to edge states which invert their chirality when the field is reversed, leading to a magnetoasymmetric electrochemical…

We study spatial correlations in the ground state of a one-dimensional electron gas coupled to a dynamic quantum impurity. The system displays a non-trivial many-body effect known as the Fermi edge singularity: transitions between discrete…

We consider charge transport through a nanoscopic object, e.g. single molecules, short nanotubes, or quantum dots, that is weakly coupled to metallic electrodes. We account for several levels of the molecule/quantum dot with level-dependent…

The chiral edge modes of a topological superconductor support two types of excitations: fermionic quasiparticles known as Majorana fermions and $\pi$-phase domain walls known as edge vortices. Edge vortices are injected pairwise into…

We investigate theoretically the V-I characteristics and voltage noise of superconducting tunnel junctions with small critical current via the matrix-continued-fraction method. Special attention is paid to the large hysteresis in the V-I…

Shot noise of quantum ring (QR) excitons in a p-i-n junction surrounded by a microcavity is investigated theoretically. Some radiative decay properties of a QR exciton in a microcavity can be obtained from the observation of the current…

We review results on evaluation of loss of information in quantum registers due to their interactions with the environment. It is demonstrated that an optimal measure of the level of quantum noise effects can be introduced via the maximal…

Magnetic flux noise is a dominant source of dephasing and energy relaxation in superconducting qubits. The noise power spectral density varies with frequency as $1/f^\alpha$ with $\alpha \sim 1$ and spans 13 orders of magnitude. Recent work…

We analyze the shot noise in a voltage biased superconducting quantum point-contact. Results are presented for the single channel case with arbitrary transmission. In the limit of very low transmission it is found that the effective charge,…

We have studied the distribution of equilibrium edge current density in 2D system in a strong (quantizing) magnetic field. The case of half plane in normal magnetic field has been considered. The transition from classical strong magnetic…