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Related papers: Noise in a Superconducting Quantum Point Contact

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We measure the noise added by an atomic point contact operated as a displacement detector. With a microwave technique, we increase the measurement speed of atomic point contacts by a factor of 500. The measurement is then fast enough to…

Mesoscale and Nanoscale Physics · Physics 2008-11-08 N. E. Flowers-Jacobs , D. R. Schmidt , K. W. Lehnert

We have calculated the finite-frequency current noise of a superconductor-ferromagnet quantum point contact (SF QPC). This signal is qualitatively affected by the spin-dependence of interfacial phase shifts (SDIPS) acquired by electrons…

Mesoscale and Nanoscale Physics · Physics 2009-02-23 Audrey Cottet , Benoit Doucot , Wolfgang Belzig

We report on direct measurements of the electronic shot noise of a quantum point contact at frequencies nu in the range 4-8 GHz. The very small energy scale used ensures energy independent transmissions of the few transmitted electronic…

Mesoscale and Nanoscale Physics · Physics 2008-04-22 Eva Zakka-Bajjani , Julien Segala , Fabien Portier , Patrice Roche , Christian Glattli , Antonella Cavanna , Yong Jin

We study the conductance and current noise of a superconductor/ferromagnet (S/F) single channel Quantum Point Contact (QPC) as a function of the QPC bias voltage, using a scattering approach. We show that the Spin-Dependence of Interfacial…

Superconductivity · Physics 2009-11-13 Audrey Cottet , Wolfgang Belzig

This paper has been withdrawn by the author and replaced by arXiv:0809.4751

Mesoscale and Nanoscale Physics · Physics 2008-10-22 M. Q. Weng

We comment on some aspects of the paper entitled "Evanescent-wave Johnson noise in small devices" recently posted by V. N. Premakumar, M. G. Vavilov and R. Joynt.

Mesoscale and Nanoscale Physics · Physics 2017-07-17 Rémi Carminati , Boris Shapiro

The principal aim of this Comment is to correct those entropic uncertainty relations that are presented in a paper by Massar [arXiv:quant-ph/0703036v2 (current version)], concerning two approaches to a study of the noise produced by POVM's.…

Quantum Physics · Physics 2009-02-18 Alexey E. Rastegin

I. Introduction II. Electrons at the Fermi level III. Conductance quantization of a quantum point contact IV. Optical analogue of the conductance quantization V. Classical electron focusing VI. Electron focusing as a transmission problem…

Mesoscale and Nanoscale Physics · Physics 2013-04-08 H. van Houten , C. W. J. Beenakker

Critical comments on the recent papers supporting the idea of resilient quantum computations are presented.

Quantum Physics · Physics 2007-05-23 Robert Alicki

We consider a superconducting quantum point contact in a circuit quantum electrodynamics setup. We study three different configurations, attainable with current technology, where a quantum point contact is coupled galvanically to a coplanar…

Superconductivity · Physics 2012-05-25 G. Romero , I. Lizuain , V. S. Shumeiko , E. Solano , F. S. Bergeret

We present a semiclassical theory of shot noise in diffusive superconductor - normal metal contacts. At subgap voltages, we reproduce the doubling of shot noise with respect to conventional normal-metal contacts, which is interpreted in…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 K. E. Nagaev , M. Buttiker

We present a theoretical analysis of the shot noise in d-wave/d-wave contacts with arbitrary transparency, including the contribution of multiple Andreev reflections. The multiple charge quanta transferred in these processes are revealed as…

Superconductivity · Physics 2009-11-07 J. C. Cuevas , M. Fogelstrom

We reply to a comment by Averin and Korotkov http://uk.arxiv.org/abs/cond-mat/0404549 on Stace and Barrett, PRL 92, 136802 (2004) http://link.aps.org/abstract/PRL/v92/e136802, showing that their specific criticisms are unfounded, and…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 T. M. Stace , S. D. Barrett

A theory is developed for the emission noise at frequency $\nu$ in a quantum dot in the presence of Coulomb interactions and asymmetric couplings to the reservoirs. We give an analytical expression for the noise in terms of the various…

Mesoscale and Nanoscale Physics · Physics 2018-03-15 A. Crépieux , S. Sahoo , T. Q. Duong , R. Zamoum , M. Lavagna

Lecture Notes for the Les Houches Summer School LXIII on Quantum Fluctuations in July 1995 to appear in Elsevier Science Publishers B.V. 1997, edited by E. Giacobino and S. Reynaud.

Quantum Physics · Physics 2007-05-23 Peter Zoller , C. W. Gardiner

In the literature, the study of electron transport in quantum devices is mainly devoted to DC properties. The fluctuations of the electrical current around these DC values, the so-called quantum noise, are much less analyzed. The…

Quantum Physics · Physics 2015-03-11 Damiano Marian , Enrique Colomés , Zhen Zhan , Xavier Oriols

Meaningful quantum computing is currently bottlenecked by the error rates of current generation Noisy Intermediate Scale Quantum (NISQ) devices. To improve the fidelity of the quantum logic gates, it is essential to recognize the…

Current quantum technologies are at the cusp of becoming useful, but still face formidable obstacles such as noise. Noise severely limits the ability to scale quantum devices to the point that they would offer an advantage over classical…

Charge detection utilizing a highly biased quantum point contact has become the most effective probe for studying few electron quantum dot circuits. Measurements on double and triple quantum dot circuits is performed to clarify a back…

Mesoscale and Nanoscale Physics · Physics 2008-05-04 D. Taubert , M. Pioro-Ladrière , D. Schröer , D. Harbusch , A. S. Sachrajda , S. Ludwig

The quantum degeneracy point approach [D. Vion et al., Science 296, 886 (2002)] effectively protects superconducting qubits from low-frequency noise that couples with the qubits as transverse noise. However, low-frequency noise in…

Quantum Physics · Physics 2014-11-19 Xiu-Hao Deng , Yong Hu , Lin Tian