English
Related papers

Related papers: Quantum and Tunnelling Capacitance in Charge and S…

200 papers

Large scale quantum computers will consist of many interacting qubits. In this paper we expand the two flux qubit coupling scheme first devised in [Phys. Rev. B {\bf 70}, 140501 (2004)] and realized in [Science {\bf 314}, 1427 (2006)] to a…

Quantum Physics · Physics 2013-05-29 Peter Groszkowski , Austin G. Fowler , Felix Motzoi , Frank K. Wilhelm

Tunnel-coupled pairs of optically active quantum dots - quantum dot molecules (QDMs) - offer the possibility to combine excellent optical properties such as strong light-matter coupling with two-spin singlet-triplet ($S-T_0$) qubits having…

Without resorting to spin-spin coupling, we propose a scalable spin quantum computing scheme assisted with a semiconductor multiple-quantum-dot structure. The techniques of single electron transitions and the nanostructure of quantum-dot…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 Wei-Min Zhang , Yin-Zhong Wu , Chopin Soo , Mang Feng

We analyze a coupling scheme for qubits in different cavities of circuit-QED architecture. In contrast to the usual scheme where the cavities are coupled by an interface capacitance we employ a bridge qubit connecting cavities to mediate…

Quantum Physics · Physics 2016-01-27 Mun Dae Kim , Jaewan Kim

A quantum dot interacting with two resonant cavity modes is described by a two-mode Jaynes-Cummings model. Depending on the quantum dot energy level scheme, the interaction of a singly doped quantum dot with a cavity photon generates…

Mesoscale and Nanoscale Physics · Physics 2016-08-31 Florian Meier , David D. Awschalom

We investigate the electronic transport through two parallel double quantum dots coupled both capacitively and via a perpendicularly aligned charge qubit. The presence of the qubit leads to a modification of the coherent tunnel amplitudes…

Mesoscale and Nanoscale Physics · Physics 2012-06-19 Christian Nietner , Gernot Schaller , Christina Pöltl , Tobias Brandes

We present time-resolved measurements of spin-flip photon-assisted tunneling and spin-flip relaxation in a doubly occupied double quantum dot. The photon-assisted excitation rate as a function of magnetic field indicates that spin-orbit…

Mesoscale and Nanoscale Physics · Physics 2016-04-18 F. R. Braakman , J. Danon , L. R. Schreiber , W. Wegscheider , L. M. K. Vandersypen

We theoretically investigate electron spin operations driven by applied electric fields in a semiconductor double quantum dot (DQD). Our model describes a DQD formed in semiconductor nanowire with longitudinal potential modulated by local…

The Hamiltonian of a charge qubit, which consists of two Josephson junctions is found within well known quantum mechanical procedure. The inductance of the qubit is included from the very beginning. It allows a selfconsistent derivation of…

Superconductivity · Physics 2007-05-23 Ya. S. Greenberg , W. Krech

The spin degree of freedom of an electron or a nucleus is one of the most basic properties of nature and functions as an excellent qubit, as it provides a natural two-level system that is insensitive to electric fields, leading to long…

Mesoscale and Nanoscale Physics · Physics 2023-07-06 Guido Burkard , Thaddeus D. Ladd , John M. Nichol , Andrew Pan , Jason R. Petta

The coherent conductance and current is calculated through two quantum dots using the Hubbard model for a single level per spin. The occurrence of negative differential conductance is demonstrated. The Ohmic conductance is calculated for…

Condensed Matter · Physics 2009-10-28 P. Pals , A. MacKinnon

Charge noise has been one of the main issues in realizing high fidelity two-qubit quantum gates in semiconductor based qubits. Here, we study the influence of quasistatic noise in quantum dot detuning on the controlled phase gate for spin…

Mesoscale and Nanoscale Physics · Physics 2023-12-21 Yinan Fang

Quantum mechanics postulates that measuring the qubit's wave function results in its collapse, with the recorded discrete outcome designating the particular eigenstate that the qubit collapsed into. We show that this picture breaks down…

The adiabatic topological pumping is proposed by periodically modulating a semiconductor nanowire double-quantum-dot chain. We demonstrate that the quantized charge transport can be achieved by a nontrivial modulation of the quantum-dot…

Mesoscale and Nanoscale Physics · Physics 2021-11-23 Zhi-Hai Liu , H. Q. Xu

One of the key pathways towards scalability of spin-based quantum computing systems lies in achieving long-range interactions between electrons and increasing their inter-connectivity. Coherent spin transport is one of the most promising…

Coupled spin evolution and tunneling together with the relaxation and decoherence effects are studied for the double quantum dot formed in a semiconductor nanowire and driven by the periodic electric field. Such system represents a model of…

Mesoscale and Nanoscale Physics · Physics 2025-02-25 D. V. Khomitsky , M. V. Bastrakova , D. S. Pashin

We propose a device acting as a spin valve which is based on a double quantum dot structure with parallel topology. Using the exact analytical solution for the noninteracting case we argue that, at a certain constellation of system…

Mesoscale and Nanoscale Physics · Physics 2010-03-18 J. P. Dahlhaus , S. Maier , A. Komnik

The rate-equation approach is used to describe sequential tunneling through a molecular junction in the Coulomb blockade regime. Such device is composed of molecular quantum dot (with discrete energy levels) coupled with two metallic…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 Kamil Walczak

We describe an electrodynamic mechanism for coherent, quantum mechanical coupling between spacially separated quantum dots on a microchip. The technique is based on capacitive interactions between the electron charge and a superconducting…

Quantum Physics · Physics 2009-11-10 L. I. Childress , A. S. Sorensen , M. D. Lukin

We present Coulomb Blockade measurements of two few-electron quantum dots in series which are configured such that the electrochemical potential of one of the two dots is aligned with spin-selective leads. The charge transfer through the…

Mesoscale and Nanoscale Physics · Physics 2016-08-16 M. Ciorga , M. Pioro-Ladrière , P. Zawadzki , J. Lapointe , Z. Wasilewski , A. S. Sachrajda