The Experts below are selected from a list of 24036 Experts worldwide ranked by ideXlab platform
Mustansir Barma - One of the best experts on this subject based on the ideXlab platform.
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comment on replica symmetry breaking in trajectories of a driven Brownian Particle
Physical Review Letters, 2018Co-Authors: Tapas Singha, Mustansir BarmaAbstract:We comment on a Letter [Phys. Rev. Lett. 115, 080605 (2015), arXiv:1411.1816] "Replica symmetry breaking in trajectories of a driven Brownian Particle" and author reply [arXiv:1805.10474]
Shinichi Sasa - One of the best experts on this subject based on the ideXlab platform.
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replica symmetry breaking in trajectories of a driven Brownian Particle
Physical Review Letters, 2015Co-Authors: Masahiko Ueda, Shinichi SasaAbstract:We study a Brownian Particle passively driven by a field obeying the noisy Burgers' equation. We demonstrate that the system exhibits replica symmetry breaking in the path ensemble with the initial position of the Particle being fixed. The key step of the proof is that the path ensemble with a modified boundary condition can be exactly mapped onto the canonical ensemble of directed polymers.
Sergio Ciliberto - One of the best experts on this subject based on the ideXlab platform.
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engineered swift equilibration of a Brownian Particle
Nature Physics, 2016Co-Authors: Ignacio A. Martínez, Artyom Petrosyan, David Gueryodelin, Emmanuel Trizac, Sergio CilibertoAbstract:A fundamental and intrinsic property of any device or natural system is its relaxation time relax, which is the time it takes to return to equilibrium after the sudden change of a control parameter [1]. Reducing τrelax, is frequently necessary, and is often obtained by a complex feedback process. To overcome the limitations of such an approach, alternative methods based on driving have been recently demonstrated [2, 3], for isolated quantum and classical systems [4-9]. Their extension to open systems in contact with a thermostat is a stumbling block for applications. Here, we design a protocol, named Engineered Swift Equilibration (ESE), that shortcuts time-consuming relaxations, and we apply it to a Brownian Particle trapped in an optical potential whose properties can be controlled in time. We implement the process experimentally, showing that it allows the system to reach equilibrium times faster than the natural equilibration rate. We also estimate the increase of the dissipated energy needed to get such a time reduction. The method paves the way for applications in micro and nano devices, where the reduction of operation time represents as substantial a challenge as miniaturization [10].
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Engineered swift equilibration of a Brownian Particle
Nature Physics, 2016Co-Authors: Ignacio Martinez, Artyom Petrosyan, Emmanuel Trizac, David Guéry-odelin, Sergio CilibertoAbstract:A fundamental and intrinsic property of any device or natural system is its relaxation time relax, which is the time it takes to return to equilibrium after the sudden change of a control parameter [1]. Reducing τ relax , is frequently necessary, and is often obtained by a complex feedback process. To overcome the limitations of such an approach, alternative methods based on driving have been recently demonstrated [2, 3], for isolated quantum and classical systems [4–9]. Their extension to open systems in contact with a thermostat is a stumbling block for applications. Here, we design a protocol,named Engineered Swift Equilibration (ESE), that shortcuts time-consuming relaxations, and we apply it to a Brownian Particle trapped in an optical potential whose properties can be controlled in time. We implement the process experimentally, showing that it allows the system to reach equilibrium times faster than the natural equilibration rate. We also estimate the increase of the dissipated energy needed to get such a time reduction. The method paves the way for applications in micro and nano devices, where the reduction of operation time represents as substantial a challenge as miniaturization [10]. The concepts of equilibrium and of transformations from an equilibrium state to another, are cornerstones of thermodynamics. A textbook illustration is provided by the expansion of a gas, starting at equilibrium and expanding to reach a new equilibrium in a larger vessel. This operation can be performed either very slowly by a piston, without dissipating energy into the environment, or alternatively quickly, letting the piston freely move to reach the new volume.
Tapas Singha - One of the best experts on this subject based on the ideXlab platform.
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comment on replica symmetry breaking in trajectories of a driven Brownian Particle
Physical Review Letters, 2018Co-Authors: Tapas Singha, Mustansir BarmaAbstract:We comment on a Letter [Phys. Rev. Lett. 115, 080605 (2015), arXiv:1411.1816] "Replica symmetry breaking in trajectories of a driven Brownian Particle" and author reply [arXiv:1805.10474]
Satya N. Majumdar - One of the best experts on this subject based on the ideXlab platform.
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Toward the full short-time statistics of an active Brownian Particle on the plane
Physical Review E, 2020Co-Authors: Satya N. Majumdar, Baruch MeersonAbstract:We study the position distribution of a single active Brownian Particle (ABP) on the plane. We show that this distribution has a compact support, the boundary of which is an expanding circle. We focus on a short-time regime and employ the optimal fluctuation method (OFM) to study large deviations of the Particle position coordinates $x$ and $y$. We determine the optimal paths of the ABP, conditioned on reaching specified values of $x$ and $y$, and the large deviation functions of the marginal distributions of $x$, and of $y$. These marginal distributions match continuously with "near tails" of the $x$ and $y$ distributions of typical fluctuations, studied earlier. We also calculate the large deviation function of the joint $x$ and $y$ distribution $P(x,y,t)$ in a vicinity of a special "zero-noise" point, and show that $\ln P(x,y,t)$ has a nontrivial self-similar structure as a function of $x$, $y$ and $t$. The joint distribution vanishes extremely fast at the expanding circle, exhibiting an essential singularity there. This singularity is inherited by the marginal $x$- and $y$-distributions. We argue that this fingerprint of the short-time dynamics remains there at all times.
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Long-time position distribution of an active Brownian Particle in two dimensions
Physical Review E, 2019Co-Authors: Urna Basu, Satya N. Majumdar, Alberto Rosso, Satya Majumdar, Gregory SchehrAbstract:We study the late time dynamics of a single active Brownian Particle in two dimensions with speed $v_0$ and rotation diffusion constant $D_R$. We show that at late times $t\gg D_R^{-1}$, while the position probability distribution $P(x,y,t)$ in the $x$-$y$ plane approaches a Gaussian form near its peak describing the typical diffusive fluctuations, it has non-Gaussian tails describing atypical rare fluctuations when $\sqrt{x^2+y^2}\sim v_0 t$. In this regime, the distribution admits a large deviation form, $P(x,y,t) \sim \exp\left[-t\, D_R\, \Phi\left(\sqrt{x^2+y^2}/(v_0 t)\right)\right]$, where we compute the rate function $\Phi(z)$ analytically and also numerically using an importance sampling method. We show that the rate function $\Phi(z)$, encoding the rare fluctuations, still carries the trace of activity even at late times. Another way of detecting activity at late times is to subject the active Particle to an external harmonic potential. In this case we show that the stationary distribution $P_\text{stat}(x,y)$ depends explicitly on the activity parameter $D_R^{-1}$ and undergoes a crossover, as $D_R$ increases, from a ring shape in the strongly active limit ($D_R\to 0$) to a Gaussian shape in the strongly passive limit $(D_R\to \infty)$.
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Steady state, relaxation and first-passage properties of a run-and-tumble Particle in one-dimension
Journal of Statistical Mechanics: Theory and Experiment, 2018Co-Authors: Kanaya Malakar, Sanjib Sabhapandit, Anupam Kundu, Satya N. Majumdar, V. Jemseena, K. Vijay Kumar, S. Redner, Abhishek DharAbstract:We investigate the motion of a run-and-tumble Particle (RTP) in one dimension. We find the exact probability distribution of the Particle with and without diffusion on the infinite line, as well as in a finite interval. In the infinite domain, this probability distribution approaches a Gaussian form in the long-time limit, as in the case of a regular Brownian Particle. At intermediate times, this distribution exhibits unexpected multi-modal forms. In a finite domain, the probability distribution reaches a steady state form with peaks at the boundaries, in contrast to a Brownian Particle. We also study the relaxation to the steady state analytically. Finally we compute the survival probability of the RTP in a semi-infinite domain. In the finite interval, we compute the exit probability and the associated exit times. We provide numerical verifications of our analytical results.
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Winding statistics of a Brownian Particle on a ring
Journal of Physics A: Mathematical and Theoretical, 2014Co-Authors: Anupam Kundu, Alain Comtet, Satya N. MajumdarAbstract:We consider a Brownian Particle moving on a ring. We study the probability distributions of the total number of turns and the net number of counter-clockwise turns the Particle makes till time t. Using a method based on the renewal properties of Brownian walker, we find exact analytical expressions of these distributions. This method serves as an alternative to the standard path integral techniques which are not always easily adaptable for certain observables. For large t, we show that these distributions have Gaussian scaling forms. We also compute large deviation functions associated to these distributions characterizing atypically large fluctuations. We provide numerical simulations in support of our analytical results.
