Publications

Below is a list of scientific articles that I have (co-) authored.

Preprints

• Information Arbitrage in Bipartite Heat Engines
  Matthew P. Leighton, Jannik Ehrich, and David A. Sivak (arXiv)
  _{Bipartite heat engines working between heat reservoirs at different temperatures must behave as information engines to produce net output work. Study of several model system illustrating the relationship between heat and information engines.}

Published Articles

1. Unlocking the potential of information flow: Maximizing free-energy transduction in a model of an autonomous rotary molecular motor
   Mathis Grelier, David A. Sivak, and Jannik Ehrich
   Physical Reviev E 109, 034115 (2024) (arXiv)
   _{Optimization of a discrete-state model of the molecular motor FoF1 ATP-synthase for output power, finding that information transduction is not needed for optimal performance in isothermal conditions. When the two machine components are in contact with heat baths at different temperatures, information flow becomes a valuable ressource.}

2. Information engine in a nonequilibrium bath
   Tushar K. Saha, Jannik Ehrich, Momčilo Gavrilov, Susanne Still, David A. Sivak, and John Bechhoefer
   Physical Reviev Letters 131, 057101 (2023) (arXiv
   _{Experimental study of an information ratchet subjected to additional nonequilibrium fluctuations, boosting output power by up to an order of magnitude, and theoretical analysis of engine efficiency showing that information engines in nonequilibrium baths can greatly outperform conventional engines}

3. Energetic cost of feedback control
   Jannik Ehrich, Susanne Still, and David A. Sivak
   Physical Reviev Research 5, 023080 (2023) (arXiv)
   _{Analysis of a thermodynamic process with repeated feedback, emphasizing that the controller is a physical system interacting with the feedback-controlled subsystem through interaction potentials, and derivation of minimal work needed to achieve feedback control}

4. Energy and information flows in autonomous systems
   Jannik Ehrich and David A. Sivak
   Frontiers in Physics 11, 1108357 (2023) (arXiv)
   _{Review of recent progress in the study of information flow in bipartite stochastic systems, such as biomolecular sensors and strongly-coupled two-component molecular machines, and gentle introduction into the information-flow formalism}

5. Bayesian information engine that optimally exploits noisy measurements
   Tushar K. Saha, Joseph N. E. Lucero, Jannik Ehrich, David A. Sivak, and John Bechhoefer
   Physical Review Letters 129, 130601 (2022) (arXiv)
   (Editors’ Suggestion, Synopsis in Physics)
   _{Experimental realization of an information ratchet with measurement errors, phase transition in performance at a critical signal-to-noise ratio below which no work extraction is possible, and Bayesian estimates of system positions drastically increases performance}

6. Maximal fluctuation exploitation in Gaussian information engines
   Joseph N. E. Lucero, Jannik Ehrich, John Bechhoefer, and David A. Sivak
   Physical Review E 103, 022140 (2021) (arXiv)
   _{Analysis of masked Markovian jump process, comparison of different lower bounds on entropy production from partial observation, and calculation of tightest bound by fitting a generating model to the observable data}

7. Tightest bound on hidden entropy production from partially observed dynamics
   Jannik Ehrich
   Journal of Statistical Mechanics: Theory and Experiment, 083214 (2021) (arXiv)
   _{Exploration of performance limits of a model of a realistic information engine that can store output energy, finding that restricting engine output to work against external force can limit information-to-energy performance, and investigation of tradeoff between input work and output work}

8. Maximizing power and velocity of an information engine
   Tushar K. Saha, Joseph N. E. Lucero, Jannik Ehrich, David A. Sivak, and John Bechhoefer
   Proc. Natl. Acad Sci. USA 118, e2023356118 (2021) (arXiv)
   (News coverage on SFU News, see PNAS Commentary)
   _{Experimental realization of an “information ratchet” which rectifies thermal fluctuations of a micron-sized bead to lift it against gravity, optimization via theory of mean first-passage times, power and velocity an order of magnitude higher than in previously reported engines}

9. Free energy transduction within autonomous systems
   Steven J. Large, Jannik Ehrich, and David A. Sivak
   Physical Review E 103, 022140 (2021) (arXiv)
   _{Introduction of TAFER (transduced additional free energy rate) to quantify how one part of a strongly coupled system drives another (“downstream”) part, illustration with a model system, and connection to excess power and entropy production}

10. Optimal finite-time bit erasure under full control
    Karel Proesmans, Jannik Ehrich, and John Bechhoefer
    Physical Review E 102, 032105 (2020) (arXiv)
    _{Generalization of finite-time Landauer principle to partial erasure, detailed study of example systems, and full details of derivation of bounds on minimum dissipation}

11. Finite-time Landauer Principle
    Karel Proesmans, Jannik Ehrich, and John Bechhoefer
    Physical Review Letters 125, 100602 (2020) (arXiv)
    (Editors’ Suggestion, featured on phys.org)
    _{Refined Landauer limit for bit erasure in finite time, simple bounds on erasure cost, and a method for finding minimum-dissipation erasure protocols}

12. Micro-reversibility and thermalization with collisional baths
    Jannik Ehrich, Massimiliano Esposito, Felipe Barra, and Juan M.R. Parrondo
    Physica A 552, 122108 (2020) (arXiv)
    _{Semi-classical analysis of a system in a collisional bath, showing how micro-reversibility needs all canonical variables and conservation of phase-space volume, and that, otherwise, violations of the second law emerge}

13. Approximating microswimmer dynamics by active Brownian motion: Energetics and efficiency
    Jannik Ehrich and Marcel Kahlen
    Physical Review E 99, 012118 (2019) (arXiv)
    _{Dynamics of a microswimmer are shown to approximate active Brownian motion, comparison of energy dissipation rates of approximation and full model, introduction of a swimming efficiency}

14. Hidden slow degrees of freedom and fluctuation theorems: an analytically solvable model
    Marcel Kahlen and Jannik Ehrich
    Journal of Statistical Mechanics: Theory and Experiment, 063204 (2018) (arXiv)
    _{Analytically tractable model illustrating how unobserved degrees of freedom modify fluctuation theorems for the apparent entropy production and calculation of full, non-Markovian marginal entropy production via path integrals}

15. Stochastic thermodynamics of interacting degrees of freedom: Fluctuation theorems for detached path probabilities
    Jannik Ehrich and Andreas Engel
    Physical Review E 96, 042129 (2017) (arXiv)
    _{General analysis of systems with interacting degrees of freedom, derivation of general fluctuation theorems capable of disentangling their interaction, and recovery of many known fluctuation theorems for special cases}

Thesis

Coupled and Hidden Degrees of Freedom in Stochastic Thermodynamics
Carl von Ossietzky Universität Oldenburg, 2020 (arXiv)