English
Related papers

Related papers: Non-symmetrized quantum noise in a Kondo quantum d…

200 papers

Single quantum dots are solid-state emitters which mimic two-level atoms but with a highly enhanced spontaneous emission rate. A single quantum dot is the basis for a potentially excellent single photon source. One outstanding problem is…

Solid-state systems which mimic two-level atoms are being actively developed. Improving the quantum coherence of these systems, for instance spin qubits or single photon emitters using semiconductor quantum dots, involves dealing with…

The probabilistic character of the measurement process is one of the most puzzling and fascinating aspects of quantum mechanics. In many-body systems quantum mechanical noise reveals non-local correlations of the underlying many-body…

Other Condensed Matter · Physics 2016-02-02 S. Hofferberth , I. Lesanovsky , T. Schumm , A. Imambekov , V. Gritsev , E. Demler , J. Schmiedmayer

We investigate background charge fluctuation in a GaAs quantum dot device by measuring 1/f noise in the single-electron tunneling current through the dot. The current noise is understood as fluctuations of the confinement potential and…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 S. W. Jung , T. Fujisawa , Y. H. Jeong , Y. Hirayama

We measure the current and shot noise in a quantum dot (QD) in the Kondo regime to address the non-equilibrium properties of the Kondo effect. By systematically tuning the temperature and gate voltages to define the level positions in the…

We employ a non-linear sigma model defined on a Keldysh contour to study the current and the current noise in a diffusive micro-bridge in the presence of electron-electron interactions. Out of equilibrium the fluctuation-dissipation theorem…

Mesoscale and Nanoscale Physics · Physics 2009-03-29 D. B. Gutman , Yuval Gefen

Instabilities due to extrinsic interference are routinely faced in systems engineering, and a common solution is to rely on a broad class of $\textit{filtering}$ techniques in order to afford stability to intrinsically unstable systems. For…

Quantum Physics · Physics 2015-06-19 A. Soare , H. Ball , D. Hayes , J. Sastrawan , M. C. Jarratt , J. J. McLoughlin , X. Zhen , T. J. Green , M. J. Biercuk

We calculate the radiation noise level associated with the spontaneous emission of a coherently driven medium. The significant field-induced modification of relation between the noise power and damping constant in a thermal reservoir is…

Quantum Physics · Physics 2016-04-13 Maria Erukhimova , Mikhail Tokman

In this paper, we carry out a theoretical analysis of the zero-frequency and finite-frequency shot noise in electron tunneling through a two-level interacting system connected to two leads, when a coherent coupling between the two levels is…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Ivana Djuric , Bing Dong , H. L. Cui

An approach to the problem of 1/f voltage noise in conductors is developed based on an uncertainty relation for the Fourier-transformed signal. The quantum indeterminacy caused by non-commutativity of the observables at different times…

Quantum Physics · Physics 2020-06-23 Kirill A. Kazakov

Quantum shot noise probes the dynamics of charge transfers through a quantum conductor, reflecting whether quasiparticles flow across the conductor in a steady stream, or in syncopated bursts. We have performed high-sensitivity shot noise…

We theoretically investigate a quantum dot coupled to fermionic (electronic) leads and show how zero-point quantum fluctuations stemming from bosonic environments permit the rectification of the current. The bosonic baths are either…

Mesoscale and Nanoscale Physics · Physics 2015-09-30 Loïc Henriet , Andrew N. Jordan , Karyn Le Hur

Spectral density of current fluctuations in a short ballistic superconducting quantum point contact is calculated for arbitrary bias voltages $V$. Contrary to a common opinion that the supercurrent flow in Josephson junctions is coherent…

Condensed Matter · Physics 2009-10-28 D. Averin , H. Imam

Correlation effects in the transport properties of a single quantum level coupled to electron reservoirs are discussed theoretically using a non-equilibrium Green functions approach. Our method is based on the introduction of a second-order…

Condensed Matter · Physics 2016-08-14 A. Levy Yeyati , A. Martín-Rodero , F. Flores

Having accurate tools to describe non-classical, non-Gaussian environmental fluctuations is crucial for designing effective quantum control protocols and understanding the physics of underlying quantum dissipative environments. We show how…

Quantum Physics · Physics 2020-08-14 Yu-Xin Wang , A. A. Clerk

We present a quantum calculation based on scattering theory of the frequency dependent noise of current in an interacting chaotic cavity. We include interactions of the electron system via long range Coulomb forces between the conductor and…

Mesoscale and Nanoscale Physics · Physics 2015-06-25 F. W. J. Hekking , J. P. Pekola

We calculate the frequency-dependent equilibrium noise of a mesoscopic capacitor in time-dependent density functional theory (TDDFT). The capacitor is modeled as a single-level quantum dot with on-site Coulomb interaction and tunnel…

Mesoscale and Nanoscale Physics · Physics 2018-04-23 Niklas Dittmann , Janine Splettstoesser , Nicole Helbig

Using a Fermi liquid approach, we provide a comprehensive treatment of the current and current noise through a quantum dot whose low-energy behaviour corresponds to an SU($N$) Kondo model, focusing on the case N=4 relevant to carbon…

Mesoscale and Nanoscale Physics · Physics 2009-11-23 Christophe Mora , Pavel Vitushinsky , Xavier Leyronas , Aashish A. Clerk , Karyn Le Hur

A non-equilibrium theory describing the charge qubit dynamics measured by a quantum point contact is developed based on Schwinger-Keldysh's approach. Using the real-time diagram technique, we derive the master equation to all orders in…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 Ming-Tsung Lee , Wei-Min Zhang

The theory of quantum transport through a dot under a finite bias voltage is developed using perturbation theory in the Keldysh formalism. It is found that the Kondo resonance splits into double peaks when the voltage exceeds the Kondo…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 Tatsuya Fujii , Kazuo Ueda