Thermodynamic bound on current fluctuations in coherent conductors

• URL: http://arxiv.org/abs/2507.01214v1
• Date: Tue, 01 Jul 2025 22:21:48 GMT
• Title: Thermodynamic bound on current fluctuations in coherent conductors
• Authors: Kay Brandner, Keiji Saito,
• Abstract summary: We derive a universal bound on the large-deviation functions of particle currents in coherent conductors.<n>For typical current fluctuations, we recover a recently derived thermodynamic uncertainty relation for coherent transport.
• Score: 0.0
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: We derive a universal bound on the large-deviation functions of particle currents in coherent conductors. This bound depends only on the mean value of the relevant current and the total rate of entropy production required to maintain a non-equilibrium steady state, thus showing that both typical and rare current fluctuations are ultimately constrained by dissipation. Our analysis relies on the scattering approach to quantum transport and applies to any multi-terminal setup with arbitrary chemical potential and temperature gradients, provided the transmission coefficients between reservoirs are symmetric. This condition is satisfied for any two-terminal system and, more generally, when the dynamics of particles within the conductor are symmetric under time-reversal. For typical current fluctuations, we recover a recently derived thermodynamic uncertainty relation for coherent transport. To illustrate our theory, we analyze a specific model comprising two reservoirs connected by a chain of quantum dots, which shows that our bound can be saturated asymptotically.

Related papers

• Quantum tunneling and anti-tunneling across entropic barriers [44.99833362998488]
  We study the dynamics of a quantum particle in a constricted two-dimensional channel.<n>We analyze how the onset of quantum corrections impacts the (semi-intuitive) high-temperature behaviour, as temperature is lowered.
  arXiv  Detail & Related papers  (2025-05-06T19:55:55Z)
• Symmetries, Conservation Laws and Entanglement in Non-Hermitian Fermionic Lattices [37.69303106863453]
  Non-Hermitian quantum many-body systems feature steady-state entanglement transitions driven by unitary dynamics and dissipation.<n>We show that the steady state is obtained by filling single-particle right eigenstates with the largest imaginary part of the eigenvalue.<n>We illustrate these principles in the Hatano-Nelson model with periodic boundary conditions and the non-Hermitian Su-Schrieffer-Heeger model.
  arXiv  Detail & Related papers  (2025-04-11T14:06:05Z)
• Thermodynamic Uncertainty Relations for Coherent Transport [0.0]
  We derive a universal thermodynamic uncertainty relation for Fermionic coherent transport.<n>We show that coherent thermoelectric heat engines and refrigerators can attain ideal efficiency only at vanishing mean power or diverging power fluctuations.
  arXiv  Detail & Related papers  (2025-02-11T19:45:09Z)
• Anomalous transport in U(1)-symmetric quantum circuits [41.94295877935867]
  Investigation of discrete-time transport in a generic U(1)-symmetric disordered model tuned across an array of different dynamical regimes. We develop an aggregate quantity, a circular statistical moment, which is a simple function of the magnetization profile. From this quantity we extract transport exponents, revealing behaviors across the phase diagram consistent with localized, diffusive, and - most interestingly for a disordered system - superdiffusive regimes.
  arXiv  Detail & Related papers  (2024-11-21T17:56:26Z)
• Quantum many-body spin ratchets [0.0]
  We show that breaking of space-reflection symmetry results in a drift in the dynamical spin susceptibility.<n>We also show that the scaled cumulant generating function of the time-integrated current instead obeys a generalized fluctuation relation.
  arXiv  Detail & Related papers  (2024-06-03T17:51:36Z)
• Emergent Anomalous Hydrodynamics at Infinite Temperature in a Long-Range XXZ Model [14.297989605089663]
  We find anomalous hydrodynamics in a spin-1/2 XXZ chain with power-law couplings. We quantify the degree of quantum chaos using the Kullback-Leibler divergence. This work offers another deep understanding of emergent anomalous transport phenomena in a wider range of non-integrable quantum many-body systems.
  arXiv  Detail & Related papers  (2024-03-26T17:50:04Z)
• Dispersive Non-reciprocity between a Qubit and a Cavity [24.911532779175175]
  We present an experimental study of a non-reciprocal dispersive-type interaction between a transmon qubit and a superconducting cavity. We show that the qubit-cavity dynamics is well-described in a wide parameter regime by a simple non-reciprocal master-equation model.
  arXiv  Detail & Related papers  (2023-07-07T17:19:18Z)
• Dynamics of large deviations in the hydrodynamic limit: Non-interacting systems [0.0]
  We study the dynamics of the energy transferred across a point along a quantum chain. We consider the transverse field Ising and harmonic chains as prototypical models of non-interacting fermionic and bosonic excitations.
  arXiv  Detail & Related papers  (2020-07-23T16:33:58Z)
• Probing eigenstate thermalization in quantum simulators via fluctuation-dissipation relations [77.34726150561087]
  The eigenstate thermalization hypothesis (ETH) offers a universal mechanism for the approach to equilibrium of closed quantum many-body systems. Here, we propose a theory-independent route to probe the full ETH in quantum simulators by observing the emergence of fluctuation-dissipation relations. Our work presents a theory-independent way to characterize thermalization in quantum simulators and paves the way to quantum simulate condensed matter pump-probe experiments.
  arXiv  Detail & Related papers  (2020-07-20T18:00:02Z)
• Coherent Transport in Periodically Driven Mesoscopic Conductors: From Scattering Matrices to Quantum Thermodynamics [0.0]
  Floquet scattering amplitudes describe the transition of a transport carrier through a periodically driven sample. We show that this framework is inherently consistent with the first and the second law of thermodynamics. We derive a generalized Green-Kubo relation, which makes it possible to express the response of any mean currents to small variations of temperature and chemical potential.
  arXiv  Detail & Related papers  (2020-02-25T17:34:31Z)
• Quantum transport between finite reservoirs [5.570257942336495]
  When driven by a potential bias between two finite reservoirs, the particle current across a quantum system evolves from an initial loading through a coherent, followed by a metastable phase, and ultimately fades away upon equilibration. We formulate a theory which fully accounts for the associated, distinct time scales, and identifies the parameter dependence of the decay rate which ultimately controls the convergence towards equilibrium.
  arXiv  Detail & Related papers  (2020-02-05T16:09:40Z)

This list is automatically generated from the titles and abstracts of the papers in this site.

This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.