English
Related papers

Related papers: Many-Body Effects in a Molecular Quantum NAND Tree

200 papers

Quantum computers comprise elementary logic gates that initialize, control and measure delicate quantum states. One of the most important gates is the controlled-NOT, which is widely used to prepare two-qubit entangled states. The…

Quantum Physics · Physics 2024-01-04 Robert J. Chapman , Samuel Häusler , Giovanni Finco , Fabian Kaufmann , Rachel Grange

We study thermal conductance and thermopower of a metallic single-electron transistor beyond the limit of weak tunnel coupling. Employing both a systematic second-order perturbation expansion and a non-perturbative approximation scheme, we…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Björn Kubala , Jürgen König

The formalism for a linear-response many-body treatment of the electronic contributions to thermal transport is developed for multilayered nanostructures. By properly determining the local heat-current operator, it is possible to show that…

Strongly Correlated Electrons · Physics 2007-05-23 J. K. Freericks , V. Zlatic , A. M. Shvaika

In this Letter we study thermoelectric effects in ultra small quantum dots. We study the behaviour of the thermopower, Peltier coefficient and thermal conductance both in the sequencial tunneling regime and in the regime where Kondo…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 Daniel Boese , Rosario Fazio

We consider quantum computer architectures where interactions are mediated between hot qubits that are not in their mechanical ground state. Such situations occur, e.g., when not cooling ideally, or when moving ions or atoms around. We…

Quantum Physics · Physics 2024-07-26 Ferran Riera-Sàbat , Pavel Sekatski , Wolfgang Dür

Theoretical research into many-body quantum systems has mostly focused on regular structures which have a small, simple unit cell and where a vanishingly small number of pairs of the constituents directly interact. Motivated by advances in…

Quantum Physics · Physics 2022-12-06 Joseph Tindall , Amy Searle , Abdulla Alhajri , Dieter Jaksch

We theoretically show how structural modifications and controlling quantum coherency can enhance linear and nonlinear thermoelectric performance in graphene nanostructure heat engines. Although graphene has emerged as a promising material…

Mesoscale and Nanoscale Physics · Physics 2024-05-24 Yuga Kodama , Nobuhiko Taniguchi

Understanding thermal transport in nanoscale systems presents important challenges to both theory and experiment. In particular, the concept of local temperature at the nanoscale appears difficult to justify. Here, we propose a novel…

Mesoscale and Nanoscale Physics · Physics 2015-08-05 Robert Biele , Roberto D'Agosta , Angel Rubio

During the last decades, quantum dots within the Coulomb blockade regime of transport have been proposed as essential building blocks for a wide variety of nanomachines. This includes thermoelectric devices, quantum shuttles, quantum pumps,…

Mesoscale and Nanoscale Physics · Physics 2021-05-03 Federico D. Ribetto , Raúl A. Bustos-Marún , Hernan L. Calvo

A set of stacked two-dimensional electron systems in a perpendicular magnetic field exhibits a three-dimensional version of the quantum Hall effect if interlayer tunneling is not too strong. When such a sample is in a quantum Hall plateau,…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 J. W. Tomlinson , J. -S. Caux , J. T. Chalker

We study transport through multiply coupled carbon nano-tubes (quantum wires) and compute the conductances through the two wires as a function of the two gate voltages $g_1$ and $g_2$ controlling the chemical potential of the electrons in…

Mesoscale and Nanoscale Physics · Physics 2007-12-03 Sourin Das , Sumathi Rao

The effect of electric field, applied on systems in the nanoscale regime has attracted a lot of research in recent times. We highlight some of the recent results in the field of single molecule electronics and then move on to focus on some…

Materials Science · Physics 2008-10-11 S. Lakshmi , Sudipta Dutta , Swapan K. Pati

The key to explaining a wide range of quantum phenomena is understanding how entanglement propagates around many-body systems. Furthermore, the controlled distribution of entanglement is of fundamental importance for quantum communication…

Quantum Physics · Physics 2014-07-16 P. Jurcevic , B. P. Lanyon , P. Hauke , C. Hempel , P. Zoller , R. Blatt , C. F. Roos

In this paper we study the thermopower of a quantum dot connected to two leads in the presence of Kondo correlation by employing a modified second-order perturbation scheme at nonequilibrium. A simple scheme, Ng's ansatz [Phys. Rev. Lett.…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 Bing Dong , X. L. Lei

Three terminal tunnelling experiments on quantum dots in the Coulomb blockade regime allow a quantitative determination of the coupling strength of individual quantum states to the leads. Exploiting this insight we have observed independent…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 R. Leturcq , D. Graf , T. Ihn , K. Ensslin , D. D. Driscoll , A. C. Gossard

The correspondence principle bridges the quantum and classical worlds by establishing a direct link between their dynamics. This well-accepted tenant of quantum physics has been explored in quantum systems wherein the number of particles is…

We analyze the problem of directed quantum transport induced by external exponentially correlated telegraphic noise. In addition to quantum nature of the heat bath, nonlinearity of the periodic system potential brings in quantum…

Statistical Mechanics · Physics 2007-05-23 Pulak Kumar Ghosh , Debashis Barik , Deb Shankar Ray

The energy efficiency and power of a three-terminal thermoelectric nanodevice are studied by considering elastic tunneling through a single quantum dot. Facilitated by the three-terminal geometry, the nanodevice is able to generate…

Mesoscale and Nanoscale Physics · Physics 2017-08-22 Jincheng Lu , Rongqian Wang , Yefeng Liu , Jian-Hua Jiang

Classical thermodynamics is unrivalled in its range of applications and relevance to everyday life. It enables a description of complex systems, made up of microscopic particles, in terms of a small number of macroscopic quantities, such as…

Quantum Physics · Physics 2016-01-13 James Millen , André Xuereb

Energy transport is of central importance in understanding a wide variety of transitions of physical states in nature. Recently, the coherence and noise have been identified for their existence and key roles in energy transport processes,…