English
Related papers

Related papers: Thermal fluctuations in macroscopic quantum memory

200 papers

We formulate a general theory of thermal fluctuations within causal second-order viscous hydrodynamic evolution of matter formed in relativistic heavy-ion collisions. The fluctuation is treated perturbatively on top of a boost-invariant…

Nuclear Theory · Physics 2018-05-16 Chandrodoy Chattopadhyay , Rajeev S. Bhalerao , Subrata Pal

We investigate the number fluctuations in small cells of quantum gases pointing out important deviations from the thermodynamic limit fixed by the isothermal compressibility. Both quantum and thermal fluctuations in weakly as well as highly…

Quantum Gases · Physics 2011-09-30 M. Klawunn , A. Recati , L. P. Pitaevskii , S. Stringari

We study the effect of thermal blurring caused by the use of (momentum-space) rapidity as a proxy of coordinate-space rapidity in experimental measurements of conserved charge fluctuations in relativistic heavy ion collisions. In…

Nuclear Theory · Physics 2016-10-19 Yutaro Ohnishi , Masakiyo Kitazawa , Masayuki Asakawa

In this paper, we explore the possibility of building a quantum memory that is robust to thermal noise using large $N$ matrix quantum mechanics models. First, we investigate the gauged $SU(N)$ matrix harmonic oscillator and different ways…

Quantum Physics · Physics 2022-11-18 ChunJun Cao , Gong Cheng , Brian Swingle

When a second-order magnetic phase transition is tuned to zero temperature by a non-thermal parameter, quantum fluctuations are critically enhanced, often leading to the emergence of unconventional superconductivity. In these `quantum…

The displacement fluctuations of mirrors in optomechanical devices, induced via thermal expansion by temperature fluctuations due either to thermodynamic fluctuations or to fluctuations in the photon absorption, can be made smaller than…

General Relativity and Quantum Cosmology · Physics 2009-10-31 M. Cerdonio , L. Conti , A. Heidmann , M. Pinard

Magnetic relaxation in a MgB$_2$ superconductor was measured. The temperature dependence of the normalized relaxation rate was determined for three different magnetic fields. By extrapolating these rates to T=0 K, we find that these…

Superconductivity · Physics 2009-11-07 Y. Z. Zhang , R. Deltour , H. H. Wen , C. Q. Jin , Y. M. Ni , S. L Jia , G. C. Che , Z. X. Zhao

We propose and study a realistic model for the decoherence of topological qubits, based on Majorana fermions in one-dimensional topological superconductors. The source of decoherence is the fluctuating charge on a capacitively coupled gate,…

Mesoscale and Nanoscale Physics · Physics 2012-08-14 Manuel J. Schmidt , Diego Rainis , Daniel Loss

We derive the fluctuation theorem for quantum-state statistics that can be obtained when we initially measure the total energy of a quantum system at thermal equilibrium, let the system evolve unitarily, and record the quantum-state data…

Statistical Mechanics · Physics 2018-08-01 Naoto Tsuji , Masahito Ueda

We review some recent developments in the field of quasi-one-dimensional superconductivity. We demonstrate that low temperature properties of superconducting nanowires are essentially determined by quantum fluctuations. Smooth (Gaussian)…

Superconductivity · Physics 2022-04-18 Andrew G. Semenov , Andrei D. Zaikin

We study the conductance statistical features of ballistic electrons flowing through a chaotic quantum dot. We show how the temperature affects the universal conductance fluctuations by analyzing the influence of dephasing and thermal…

Mesoscale and Nanoscale Physics · Physics 2009-11-07 E. R. P. Alves , C. H. Lewenkopf

Nanoscale machines are strongly influenced by thermal fluctuations, contrary to their macroscopic counterparts. As a consequence, even the efficiency of such microscopic machines becomes a fluctuating random variable. Using geometric…

Statistical Mechanics · Physics 2019-04-16 Sreekanth K Manikandan , Lennart Dabelow , Ralf Eichhorn , Supriya Krishnamurthy

We review recent work on a continuum, classical theory of thermal fluctuations in two dimensional superconductors. A functional integral over a Ginzburg-Landau free energy describes the amplitude and phase fluctuations responsible for the…

Superconductivity · Physics 2007-05-23 Subir Sachdev

A superconductor is influenced by an applied magnetic field. Close to the transition temperature $T_{c}$ fluctuations dominate and the correlation length $\xi $ increases strongly when $T_{c}$ is approached. However, for nonzero magnetic…

Superconductivity · Physics 2007-05-23 T. Schneider

If phase coherence determines the superconducting transition temperature Tc in the cuprate oxides, it is of great interest to understand the role that dynamics of the phase fluctuation plays in bringing about depletion of the…

Superconductivity · Physics 2007-05-23 B. K. Chakraverty

The magnetic response is a state-defining property of superconductors. The magnetic flux penetrates type-II bulk superconductors by forming quantum vortices when the enclosed magnetic flux is equal to the magnetic flux quantum. The flux…

Superconductivity · Physics 2023-06-06 Yusuke Iguchi , Ruby Shi , Kunihiro Kihou , Chul-Ho Lee , Vadim Grinenko , Egor Babaev , Kathryn A. Moler

Quantum criticality arises when a macroscopic phase of matter undergoes a continuous transformation at zero temperature. While the collective fluctuations at quantum-critical points are being increasingly recognized as playing an important…

We derive augmented quasiclassical equations of superconductivity with the Lorentz force in the Matsubara formalism so that the charge redistribution due to supercurrent can be calculated quantitatively. Using it, we obtain an analytic…

Superconductivity · Physics 2016-05-03 Hikaru Ueki , Wataru Kohno , Takafumi Kita

The thermodynamic uncertainty relation, originally derived for classical Markov-jump processes, provides a trade-off relation between precision and dissipation, deepening our understanding of the performance of quantum thermal machines.…

Statistical Mechanics · Physics 2021-03-31 Junjie Liu , Dvira Segal

Phase fluctuations of the superconducting order parameter play a larger role in the cuprates than in conventional BCS superconductors because of the low superfluid density of a doped insulator. In this paper, we analyze an XY model of…

Superconductivity · Physics 2009-10-31 E. W. Carlson , S. A. Kivelson , V. J. Emery , E. Manousakis