English
Related papers

Related papers: Quantum Fluctuations in the Chirped Pendulum

200 papers

Many physical, chemical and biological systems can be modeled by means of random-frequency harmonic oscillator systems. Even though the noise-free evolution of harmonic oscillator systems can be easily implemented, the way to experimentally…

Classical Physics · Physics 2014-07-11 R. de J. León-Montiel , J. Svozilík , Juan P. Torres

We analyze the equilibrium frequency-dependent spin current noise and spin conductance through a quantum dot in the local moment regime. Spin current correlations behave markedly differently from charge correlations. Equilibrium spin…

Mesoscale and Nanoscale Physics · Physics 2011-12-30 C. P. Moca , I. Weymann , G. Zarand

We propose to exploit currently available tunnel ferromagnetic Josephson junctions to realize a hybrid superconducting qubit. We show that the characteristic hysteretic behavior of the ferromagnetic barrier provides an alternative and…

Appearance and origin of resonance phenomena have been studied in the annular system of underdamped Josephson junctions. If no fluxon is trapped in the system, dynamics is governed by the motion of fluxon-antifluxon pairs, while if trapped…

Superconductivity · Physics 2020-06-24 I. R. Rahmonov , J. Tekić , P. Mali , A. Irie , A. Plecenik , Yu. M. Shukrinov

Continuing our inquiry into the conditions when fluctuation-dissipation relations (FDR) may appear in the context of nonequilibrium dynamics of open quantum systems (over and beyond the conventional FDR from linear response theory) we turn…

High Energy Physics - Theory · Physics 2020-07-01 Jen-Tsung Hsiang , Bei-Lok Hu

Superoscillations, i.e., the phenomenon that a bandlimited function can temporary oscillate faster than its highest Fourier component, are being much discussed for their potential for `superresolution' beyond the diffraction limit. Here, we…

Quantum Physics · Physics 2015-10-16 Achim Kempf , Angus Prain

I study the dynamics of a Josephson junction serving as a threshold detector of fluctuations which is subjected to a general non-equilibrium electronic noise source whose characteristics is to be determined by the junction. This…

Statistical Mechanics · Physics 2009-06-04 Tomas Novotny

Critical points and phase transitions are characterized by diverging susceptibilities, reflecting the tendency of the system toward spontaneous symmetry breaking. Equilibrium statistical mechanics bounds these instabilities to occur at zero…

Mesoscale and Nanoscale Physics · Physics 2019-06-03 Orazio Scarlatella , Rosario Fazio , Marco Schiró

We present a fully quantum mechanical treatment of the nondegenerate optical parametric oscillator both below and near threshold. This is a non-equilibrium quantum system with a critical point phase-transition, that is also known to exhibit…

Quantum Physics · Physics 2009-11-10 K. Dechoum , P. D. Drummond , S. Chaturvedi , M. D. Reid

We consider the scenario of a fluctuating spacetime due to a deformed commutation relation with a fluctuating deformation parameter, or to a fluctuating metric tensor. By computing the resulting dynamics and averaging over these…

Quantum Physics · Physics 2025-04-01 Sandro Donadi , Matteo Fadel

Motivated by recent experiments on superconducting circuits consisting of a dc-voltage biased Josephson junction in series with a resonator, quantum properties of these devices far from equilibrium are studied. This includes a crossover…

Mesoscale and Nanoscale Physics · Physics 2013-12-23 Vera Gramich , Björn Kubala , Selina Rohrer , Joachim Ankerhold

Motivated by recent experiments, where a voltage biased Josephson junction is placed in series with a resonator, the classical dynamics of the circuit is studied in various domains of parameter space. This problem can be mapped onto the…

Mesoscale and Nanoscale Physics · Physics 2015-12-09 S. Meister , M. Mecklenburg , V. Gramich , J. T. Stockburger , J. Ankerhold , B. Kubala

The solution is given to the classical problem of an oscillator driven by a sinusoid of steadily-varying frequency. A closed analytical expression is obtained in the case where the Q-factor of the oscillator is high, equivalent to the…

Instrumentation and Detectors · Physics 2019-10-25 Brian Cowan , Andrew Morris-Costigliola , George Nichols

We develop a systematic theory of quantum fluctuations in the driven parametric oscillator (OPO), including the region near threshold. This allows us to treat the limits imposed by nonlinearities to quantum squeezing and noise reduction, in…

Quantum Physics · Physics 2007-05-23 S. Chaturvedi , K. Dechoum , P. D. Drummond

Spin qubits in semiconductor quantum dots are one of the promizing devices to realize a quantum processor. A better knowledge of the noise sources affecting the coherence of such a qubit is therefore of prime importance. In this work, we…

Mesoscale and Nanoscale Physics · Physics 2023-04-04 Baker Shalak , Christophe Delerue , Yann-Michel Niquet

We derive a microscopic effective action for superconducting contacts with arbitrary transmission distribution of conducting channels. Provided fluctuations of the Josephson phase remain sufficiently small our formalism allows to fully…

Superconductivity · Physics 2015-05-18 A. V. Galaktionov , A. D. Zaikin

We continue the study initiated in [arXiv:1708.02252] of the fluctuations of a strongly-coupled non-conformal plasma described holographically by Einstein gravity coupled to a dilaton with an exponential potential. The plasma approaches a…

High Energy Physics - Theory · Physics 2020-05-06 Panagiotis Betzios , Umut Gürsoy , Matti Järvinen , Giuseppe Policastro

The phase space for a periodically driven nonlinear oscillator consists of many resonance zones. Let the strength of periodic excitation and the strength of the damping be indexed by a small parameter $\varepsilon$. It is well known that,…

Probability · Mathematics 2017-02-17 Nishanth Lingala , Navaratnam Sri Namachchivaya , Ilya Pavlyukevich

Fluctuating electric fields emanating from surfaces are a primary source of decoherence in trapped ion qubits. Here, we show that superradiant phonon-induced excitation exchange between adatoms can lead to a reduction of electric field…

Quantum Physics · Physics 2022-01-17 P N Thomas Lloyd , Valentin Walther , Hossein Sadeghpour

We theoretically investigate the phase and voltage correlation dynamics, which includes both the deterministic contribution and stochastic fluctuations, under a current noise generated by a resistor including thermal and quantum…

Mesoscale and Nanoscale Physics · Physics 2021-07-27 Koichiro Furutani , Luca Salasnich