English
Related papers

Related papers: Dissipation and quantum noise in chiral circuitry

200 papers

Quantum spin Hall effect is characterized by topologically protected helical edge states. Here we study the thermal dissipation of helical edge states by considering two types of dissipation sources. The results show that the helical edge…

Mesoscale and Nanoscale Physics · Physics 2024-10-31 Jing-Yun Fang , Yu-Chen Zhuang , Ai-Min Guo , Qing-Feng Sun

Where, and how, does energy dissipation of electrical energy take place in a ballistic wire? Fully two decades after the advent of the transmissive phenomenology of electrical conductance, this deceptively simple query remains unanswered.…

Mesoscale and Nanoscale Physics · Physics 2009-01-06 Mukunda P. Das , Frederick Green

We demonstrate that persistent current in meso- and nanorings may fluctuate down to zero temperature provided the current operator does not commute with the total Hamiltonian of the system. For a model of a quantum particle on a ring we…

Mesoscale and Nanoscale Physics · Physics 2010-12-23 Andrew G. Semenov , Andrei D. Zaikin

Small differential conductance oscillations as a function of source-drain bias were observed and systematically studied in an asymmetric quantum point contact (QPC). These oscillations become significantly suppressed in a small in-plane…

Mesoscale and Nanoscale Physics · Physics 2015-06-03 Hao Zhang , Phillip M. Wu , Albert M. Chang

We present a new scheme to detect the quantum shot noise in coupled mesoscopic systems. By applying the noise thermometry to the capacitively coupled quantum point contacts (QPCs) we prove that the noise temperature of one QPC is in perfect…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 Masayuki Hashisaka , Yoshiaki Yamauchi , Shuji Nakamura , Shinya Kasai , Teruo Ono , Kensuke Kobayashi

The behavior of total purely quantum correlation (discord) in dimers consisting of dipolar-coupled spins 1/2 is studied. We found that the discord Q=0 at the absolute zero temperature. With increasing the temperature $T$, at first the…

Quantum Physics · Physics 2013-01-24 E. I. Kuznetsova , M. A. Yurishchev

Studies of energy flow in quantum systems complement the information provided by common conductance measurements. The quantum limit of heat flow in one dimensional (1D) ballistic modes was predicted, and experimentally demonstrated, to have…

Mesoscale and Nanoscale Physics · Physics 2021-02-02 Amir Rosenblatt , Sofia Konyzheva , Fabien Lafont , Noam Schiller , Jinhong Park , Kyrylo Snizhko , Moty Heiblum , Yuval Oreg , Vladimir Umansky

We consider the effect of dephasing on a quantum dot which injects single electrons on a chiral edge channel of the quantum Hall effect. Dephasing is described by the coupling of the dot to a bosonic bath which represents the…

Mesoscale and Nanoscale Physics · Physics 2014-06-02 Eiki Iyoda , Takeo Kato , Kazuki Koshino , Thierry Martin

We consider dephasing by interactions in a one-dimensional chiral fermion system (e.g. a Quantum Hall edge state). For finite-range interactions, we calculate the spatial decay of the Green's function at fixed energy, which sets the…

Mesoscale and Nanoscale Physics · Physics 2009-03-17 Clemens Neuenhahn , Florian Marquardt

We study the distribution over measurement outcomes of noisy random quantum circuits in the low-fidelity regime. We show that, for local noise that is sufficiently weak and unital, correlations (measured by the linear cross-entropy…

Quantum Physics · Physics 2021-12-01 Alexander M. Dalzell , Nicholas Hunter-Jones , Fernando G. S. L. Brandão

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

Non-equilibrium excess noise of a short quasi one-dimensional constriction between two superconductors is considered. A general expression for the current-current correlation function valid for arbitrary temperatures and bias voltages is…

Condensed Matter · Physics 2009-10-28 J. P. Hessling , V. S. Shumeiko , Yu. M. Galperin , G. Wendin

We present a theory for the frequency-dependent current fluctuations in superconducting quantum point-contacts (SQPC) within the dc transport regime. This theory is valid for any barrier transparency between the tunnel and ballistic limits,…

Condensed Matter · Physics 2009-10-28 A. Martin-Rodero , A. Levy Yeyati , F. J. Garcia-Vidal

We consider the non-equilibrium zero frequency noise generated by a temperature gradient applied on a device composed of two normal leads separated by a quantum dot. We recall the derivation of the scattering theory for non-equilibrium…

Mesoscale and Nanoscale Physics · Physics 2022-03-14 A. Popoff , J. Rech , T. Jonckheere , L. Raymond , B. Grémaud , S. Malherbe , T. Martin

We present studies of quantum interference in a noise power spectrum in the system of two quantum dots (2QD) in a T-geometry. Performing the spectral decomposition we are able to separate local currents and distinguish between the intra-…

Mesoscale and Nanoscale Physics · Physics 2025-10-27 Bogdan R. Bułka

The quasiparticle density observed in low-temperature superconducting circuits is several orders of magnitude larger than the value expected at thermal equilibrium. The tunneling of this excess of quasiparticles across Josephson junctions…

Quantum Physics · Physics 2025-11-03 José Alberto Nava Aquino , Rogério de Sousa

We identify a noise model that ensures the functioning of an echo state network employing a gate-based quantum computer for reservoir computing applications. Energy dissipation induced by amplitude damping drastically improves the…

Quantum Physics · Physics 2025-06-24 Francesco Monzani , Emanuele Ricci , Luca Nigro , Enrico Prati

Dissipative collective effects are ubiquitous in quantum physics, and their relevance ranges from the study of entanglement in biological systems to noise mitigation in quantum computers. Here, we put forward the first fully quantum…

We investigate the power dissipated by an electronic current flowing through a quantum point contact in a two-dimensional electron gas. Based on the Landauer-B\"uttiker approach to quantum transport, we evaluate the power that is dissipated…

Mesoscale and Nanoscale Physics · Physics 2022-03-30 Carmen Blaas-Anselmi , Félix Helluin , Rodolfo A. Jalabert , Guillaume Weick , Dietmar Weinmann

In this work, drawing inspiration from the type of noise present in real hardware, we study the output distribution of random quantum circuits under practical non-unital noise sources with constant noise rates. We show that even in the…

Quantum Physics · Physics 2023-06-30 Bill Fefferman , Soumik Ghosh , Michael Gullans , Kohdai Kuroiwa , Kunal Sharma