English
Related papers

Related papers: Effect of interactions on quantum-limited detector…

200 papers

We study a quantum system composed of three interacting qubits, each coupled to a different thermal reservoir. We show how to engineer it in order to build a quantum device that is analogous to an electronic bipolar transistor. We outline…

Quantum Physics · Physics 2021-09-22 Antonio Mandarino , Karl Joulain , Melisa Domínguez Gómez , Bruno Bellomo

Quantum interference effects and decoherence mechanisms in single-molecule junctions are analyzed employing a nonequilibrium Green's function approach. Electrons tunneling through quasi-degenerate states of a nanoscale molecular junction…

Mesoscale and Nanoscale Physics · Physics 2011-07-25 R. Härtle , M. Butzin , O. Rubio-Pons , M. Thoss

We study the low temperature properties of the differential response of the current to a temperature gradient at finite voltage in a single level quantum dot including electron-electron interaction, non-symmetric couplings to the leads and…

Strongly Correlated Electrons · Physics 2018-05-04 Diego Pérez Daroca , Pablo Roura-Bas , Armando A. Aligia

We analyze quantum interference and decoherence effects in single-molecule junctions both experimentally and theoretically by means of the mechanically controlled break junction technique and density-functional theory. We consider the case…

Mesoscale and Nanoscale Physics · Physics 2012-09-26 Stefan Ballmann , Rainer Härtle , Pedro B. Coto , Marcel Mayor , Mark Elbing , Martin R. Bryce , Michael Thoss , Heiko B. Weber

We present theoretical calculations and experimental measurements which reveal the Luttinger-liquid (LL) nature of elementary excitations in a system consisting of two quantum wires connected by a long narrow tunnel junction at the edge of…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 Yaroslav Tserkovnyak , Bertrand I. Halperin , Ophir M. Auslaender , Amir Yacoby

Although interesting per se, decoherence and relaxation of single-electron excitations induced by strong effective screened Coulomb interactions in Quantum Hall edge channels are an important challenge for the applications of electron…

Mesoscale and Nanoscale Physics · Physics 2018-10-10 C. Cabart , B. Roussel , G. Fève , P. Degiovanni

We investigate the extent to which ``interaction-free'' measurements perturb the state of quantum systems. We show that the absence of energy exchange during the measurement is not a sufficient criterion to preserve that state, as the…

Quantum Physics · Physics 2009-11-06 S. Potting , E. S. Lee , W. Schmitt , I. Rumyantsev , B. Mohring , P. Meystre

The tip of a low-temperature scanning tunneling microscope is brought into contact with individual Kondo impurities (cobalt atoms) adsorbed on a Cu(100) surface. A smooth transition from the tunneling regime to a point contact with a…

Strongly Correlated Electrons · Physics 2007-05-23 N. Neel , J. Kroeger , L. Limot , K. Palotas , W. A. Hofer , R. Berndt

We develop a new unified theoretical approach enabling us to non-perturbatively study the effect of electron-electron interactions on weak localization in arbitrary arrays of quantum dots. Our model embraces (i) weakly disordered conductors…

Mesoscale and Nanoscale Physics · Physics 2008-07-22 D. Golubev , A. Zaikin

We develope a theory of a fundamental effect of the interaction-induced decoherence of the electron wave function in a disordered metal. With the aid of the Keldysh technique and the path integral formalism we derive a formally exact…

Condensed Matter · Physics 2007-05-23 Dmitrii S. Golubev , Andrei D. Zaikin

We quantify the quantum correlations between two accelerated detectors coupled to a scalar field in a cavity. It has been realized that an accelerated detector will experience a thermal bath, which is termed the Unruh effect. We examine the…

Quantum Physics · Physics 2021-12-22 He Wang , Jin Wang

The dephasing of a qubit coupled with a point-contact detector is theoretically studied. We calculate the time evolution of the reduced density matrix of qubit by using the perturbation expansion. We show that the dephasing rate is…

We study the conductance of a quantum T-junction coupled to two electron reservoirs and a quantum dot. In the absence of electron-electron interactions, the conductance $g$ is sensitive to interference between trajectories which enter the…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 A. A. Clerk , P. W. Brouwer , V. Ambegaokar

We formulate general conditions necessary for a linear-response detector to reach the quantum limit of measurement efficiency, where the measurement-induced dephasing rate takes on its minimum possible value. These conditions are applicable…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 A. A. Clerk , S. M. Girvin , A. D. Stone

We study electron-electron interaction effects in the thermodynamic properties of quantum-dot systems. We obtain the direct and exchange contributions to the specific heat C_v in the self-consistent Hartree-Fock approximation at finite…

Mesoscale and Nanoscale Physics · Physics 2009-01-23 Luis G. Dias da Silva , Nelson Studart

In this work, we investigate the thermal quantum correlations in two coupled double semiconductor charge qubits. This is carried out by deriving analytical expressions for both the thermal concurrence and the correlated coherence. We study,…

Quantum Physics · Physics 2023-07-19 Cleverson Filgueiras , Onofre Rojas , Moises Rojas

Recently, a logarithmic decrease of conductivity has been observed in topological insulators at low temperatures, implying a tendency of localization of surface electrons. Here, we report quantum transport experiments on the topological…

Mesoscale and Nanoscale Physics · Physics 2014-10-09 Hong-Chao Liu , Hai-Zhou Lu , Hong-Tao He , Baikui Li , Shi-Guang Liu , Qing Lin He , Gan Wang , Iam Keong Sou , Shun-Qing Shen , Jiannong Wang

We consider a transmission of electrons through a two-dimensional ballistic point contact in the low-conductance regime below the 0.7-anomaly. The scattering of electrons by Friedel oscillations of charge density results in a contribution…

Mesoscale and Nanoscale Physics · Physics 2013-01-10 Tatiana Krishtop , Kirill Nagaev

We review mechanisms of low-temperature electronic transport through a quantum dot weakly coupled to two conducting leads. Transport in this case is dominated by electron-electron interaction. At temperatures moderately lower than the…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 M. Pustilnik , L. I. Glazman

Properties of the "electron gas" - in which conduction electrons interact by means of Coulomb forces but ionic potentials are neglected - change dramatically depending on the balance between kinetic energy and Coulomb repulsion. The limits…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Amit Ghosal , A. D. Guclu , C. J. Umrigar , Denis Ullmo , Harold U. Baranger