Resonant activation in piecewise linear asymmetric potentials

Fiasconaro, Alessandro; Spagnolo, Bernardo

doi:10.1103/physreve.83.041122

Cited by 90 publications

(46 citation statements)

References 53 publications

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“…5), where another resonance appears at a frequency that can be also much smaller than the geometric resonance. The position of this resonance dip depends upon the phase and signal temperature [23], so it can be considered a stochastic resonance [8,26,27,44] or resonant activation [19,21,57]. In Ref.…”

Section: Josephson Junction Detector: Performance Evaluationmentioning

confidence: 99%

Escape Time of Josephson Junctions for Signal Detection

Addesso

Филатрелла

Pierro

2012

Progress in Optical Science and Photonics

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In this Chapter we investigate with the methods of signal detection the response of a Josephson junction to a perturbation to decide if the perturbation contains a coherent oscillation embedded in the background noise. When a Josephson Junction is irradiated by an external noisy source, it eventually leaves the static state and reaches a steady voltage state. The appearance of a voltage step allows to measure the time spent in the metastable state before the transition to the running state, thus defining an escape time. The distribution of the escape times depends upon the characteristics of the noise and the Josephson junction. Moreover, the properties of the distribution depends on the features of the signal (amplitude, frequency and phase), which can be therefore inferred through the appropriate signal processing methods. Signal detection with JJ is interesting for practical purposes, inasmuch as the superconductive elements can be (in principle) cooled to the absolute zero and therefore can add (in practice) as little intrinsic noise as refrigeration allows. It is relevant that the escape times bear a hallmark of the noise itself. The spectrum of the fluctuations due to the intrinsic classical (owed to thermal or environmental disturbances) or quantum (due to the tunnel across the barrier) sources are different. Therefore, a careful analysis of the escape times could also assist to discriminate the nature of the noise.

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Section: Josephson Junction Detector: Performance Evaluationmentioning

confidence: 99%

Escape Time of Josephson Junctions for Signal Detection

Addesso

Филатрелла

Pierro

2012

Progress in Optical Science and Photonics

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“…1). Only recently it was realised that an asymmetry in this kind of potential is important for escape properties in resonant activation [6,7]. The asymmetry of the potential also plays a crucial role in systems with periodic potentials relevant to molecular motor models [8,9,10], or for molecular shuttles in suprachemical compounds [11].…”

Section: Introductionmentioning

confidence: 99%

How a finite potential barrier decreases the mean first-passage time

Palyulin¹,

Metzler²

2012

J. Stat. Mech.

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Abstract. We consider the mean first passage time of a random walker moving in a potential landscape on a finite interval, starting and end points being at different potentials. From analytical calculations and Monte Carlo simulations we demonstrate that the mean first passage time for a piecewise linear curve between these two points is minimised by introduction of a potential barrier. Due to thermal fluctuations this barrier may be crossed. It turns out that the corresponding expense for this activation is less severe than the gain from an increased slope towards the end point. In particular, the resulting mean first passage time is shorter than for a linear potential drop between the two points.

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“…Almost all curves of Figure 3 clearly show the presence of resonant activation [14,17,80,81,91,116,118,[128][129][130][131][132][133][134][135], specifically stochastic resonance activation [17,78,80,117], a noise induced phenomenon whose signature is the appearance of a minimum in the curve of MST vs ω.…”

Section: Long Jj-resultsmentioning

confidence: 99%

“…In Figure 1a two different kinds of RA can be clearly distinguished. The dynamic resonant activation (DRA), which occurs for low noise intensities as the external driving frequency is close to the natural characteristic frequency of the system, that is the plasma frequency of the JJ [80,[113][114][115], and the stochastic resonant activation (SRA), which occurs for driving frequencies close to the inverse of the average escape time at the minimum, i.e., the mean escape time over the potential barrier in the lowest configuration [78,80,116,117]. For i 0 = 0.1, the DRA effect is characterized by two minima, which appearance is related to as many escape resonance phenomena, one through the right potential barrier and the other through the left one.…”

Section: Short Graphene Jj-resultsmentioning

confidence: 99%

Nonlinear Relaxation Phenomena in Metastable Condensed Matter Systems

Spagnolo

Guarcello

Magazzù

et al. 2016

Entropy

Self Cite

100

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Nonlinear relaxation phenomena in three different systems of condensed matter are investigated. (i) First, the phase dynamics in Josephson junctions is analyzed. Specifically, a superconductor-graphene-superconductor (SGS) system exhibits quantum metastable states, and the average escape time from these metastable states in the presence of Gaussian and correlated fluctuations is calculated, accounting for variations in the the noise source intensity and the bias frequency. Moreover, the transient dynamics of a long-overlap Josephson junction (JJ) subject to thermal fluctuations and non-Gaussian noise sources is investigated. Noise induced phenomena are observed, such as the noise enhanced stability and the stochastic resonant activation. (ii) Second, the electron spin relaxation process in a n-type GaAs bulk driven by a fluctuating electric field is investigated. In particular, by using a Monte Carlo approach, we study the influence of a random telegraph noise on the spin polarized transport. Our findings show the possibility to raise the spin relaxation length by increasing the amplitude of the external fluctuations. Moreover, we find that, crucially, depending on the value of the external field strength, the electron spin depolarization length versus the noise correlation time increases up to a plateau. (iii) Finally, the stabilization of quantum metastable states by dissipation is presented. Normally, quantum fluctuations enhance the escape from metastable states in the presence of dissipation. We show that dissipation can enhance the stability of a quantum metastable system, consisting of a particle moving in a strongly asymmetric double well potential, interacting with a thermal bath. We find that the escape time from the metastable region has a nonmonotonic behavior versus the system-bath coupling and the temperature, producing a stabilizing effect.Keywords: metastability; nonequilibrium statistical mechanics and nonlinear relaxation time; noise enhanced stability; Josephson junction; spin polarized transport in semiconductors; open quantum systems; quantum noise enhanced stability

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Resonant activation in piecewise linear asymmetric potentials

Cited by 90 publications

References 53 publications

Escape Time of Josephson Junctions for Signal Detection

Escape Time of Josephson Junctions for Signal Detection

How a finite potential barrier decreases the mean first-passage time

Nonlinear Relaxation Phenomena in Metastable Condensed Matter Systems

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