Professor JUAN GARRAHAN's Outputs (93)

Efficient post-selection in light cone correlations of monitored quantum circuits (2025)
Journal Article
Li, J., Jack, R. L., Bertini, B., & Garrahan, J. P. (2025). Efficient post-selection in light cone correlations of monitored quantum circuits. Physical Review B, 111(2), Article 024309. https://doi.org/10.1103/physrevb.111.024309

We consider how to target evolution conditioned on atypical measurement outcomes in monitored quantum circuits, i.e., the post-selection problem. We show that for a simple class of measurement schemes, post-selected light cone dynamical correlation f... Read More about Efficient post-selection in light cone correlations of monitored quantum circuits.

Exact results on the dynamics of the stochastic Floquet-East model (2024)
Journal Article
De Fazio, C., Garrahan, J. P., & Klobas, K. (2024). Exact results on the dynamics of the stochastic Floquet-East model. Journal of Physics A: Mathematical and Theoretical, 57(50), Article 505002. https://doi.org/10.1088/1751-8121/ad8e1c

We introduce a stochastic generalisation of the classical deterministic Floquet-East model, a discrete circuit with the same kinetic constraint as the East model of glasses. We prove exactly that, in the limit of long time and large size, this model... Read More about Exact results on the dynamics of the stochastic Floquet-East model.

Nonthermal eigenstates and slow relaxation in quantum Fredkin spin chains (2024)
Journal Article
Causer, L., Bañuls, M. C., & Garrahan, J. P. (2024). Nonthermal eigenstates and slow relaxation in quantum Fredkin spin chains. Physical Review B, 110(13), Article 134322. https://doi.org/10.1103/physrevb.110.134322

We study the dynamics and thermalization of the Fredkin spin chain, a system with local three-body interactions, particle conservation, and explicit kinetic constraints. We consider deformations away from its stochastic point in order to tune between... Read More about Nonthermal eigenstates and slow relaxation in quantum Fredkin spin chains.

Exact pretransition effects in kinetically constrained circuits: Dynamical fluctuations in the Floquet-East model (2024)
Journal Article
Klobas, K., De Fazio, C., & Garrahan, J. P. (2024). Exact pretransition effects in kinetically constrained circuits: Dynamical fluctuations in the Floquet-East model. Physical Review E, 110(2), Article L022101. https://doi.org/10.1103/physreve.110.l022101

We study the dynamics of a classical circuit corresponding to a discrete-time version of the kinetically constrained East model. We show that this classical "Floquet-East" model displays pre-transition behavior which is a dynamical equivalent of the... Read More about Exact pretransition effects in kinetically constrained circuits: Dynamical fluctuations in the Floquet-East model.

Combining Reinforcement Learning and Tensor Networks, with an Application to Dynamical Large Deviations (2024)
Journal Article
Gillman, E., Rose, D. C., & Garrahan, J. P. (2024). Combining Reinforcement Learning and Tensor Networks, with an Application to Dynamical Large Deviations. Physical Review Letters, 132(19), Article 197301. https://doi.org/10.1103/PhysRevLett.132.197301

We present a framework to integrate tensor network (TN) methods with reinforcement learning (RL) for solving dynamical optimization tasks. We consider the RL actor-critic method, a model-free approach for solving RL problems, and introduce TNs as the... Read More about Combining Reinforcement Learning and Tensor Networks, with an Application to Dynamical Large Deviations.

Universal and nonuniversal probability laws in Markovian open quantum dynamics subject to generalized reset processes (2024)
Journal Article
Carollo, F., Lesanovsky, I., & Garrahan, J. P. (2024). Universal and nonuniversal probability laws in Markovian open quantum dynamics subject to generalized reset processes. Physical Review E, 109(4), Article 044129. https://doi.org/10.1103/physreve.109.044129

We consider quantum-jump trajectories of Markovian open quantum systems subject to stochastic in time resets of their state to an initial configuration. The reset events provide a partitioning of quantum trajectories into consecutive time intervals,... Read More about Universal and nonuniversal probability laws in Markovian open quantum dynamics subject to generalized reset processes.

Topological phases in the dynamics of the simple exclusion process (2024)
Journal Article
Garrahan, J. P., & Pollmann, F. (2024). Topological phases in the dynamics of the simple exclusion process. Physical Review E, 109(3), Article L032105. https://doi.org/10.1103/PhysRevE.109.L032105

We study the dynamical large deviations of the classical stochastic symmetric simple exclusion process (SSEP) by means of numerical matrix product states. We show that for half-filling, long-time trajectories with a large enough imbalance between the... Read More about Topological phases in the dynamics of the simple exclusion process.

Rejection-free quantum Monte Carlo in continuous time from transition path sampling (2024)
Journal Article
Causer, L., Sfairopoulos, K., Mair, J. F., & Garrahan, J. P. (2024). Rejection-free quantum Monte Carlo in continuous time from transition path sampling. Physical Review B, 109(2), Article 024307. https://doi.org/10.1103/physrevb.109.024307

Continuous-time quantum Monte Carlo refers to a class of algorithms designed to sample the thermal distribution of a quantum Hamiltonian through exact expansions of the Boltzmann exponential in terms of stochastic trajectories which are periodic in i... Read More about Rejection-free quantum Monte Carlo in continuous time from transition path sampling.

Quantum reaction-limited reaction-diffusion dynamics of annihilation processes (2023)
Journal Article
Perfetto, G., Carollo, F., Garrahan, J. P., & Lesanovsky, I. (2023). Quantum reaction-limited reaction-diffusion dynamics of annihilation processes. Physical Review E, 108(6), Article 064104. https://doi.org/10.1103/physreve.108.064104

We investigate the quantum reaction-diffusion dynamics of fermionic particles which coherently hop in a one-dimensional lattice and undergo annihilation reactions. The latter are modelled as dissipative processes which involve losses of pairs 2A→∅, t... Read More about Quantum reaction-limited reaction-diffusion dynamics of annihilation processes.

General upper bounds on fluctuations of trajectory observables (2023)
Journal Article
Bakewell-Smith, G., Girotti, F., Guţǎ, M., & Garrahan, J. P. (2023). General upper bounds on fluctuations of trajectory observables. Physical Review Letters, 131(19), Article 197101. https://doi.org/10.1103/PhysRevLett.131.197101

Thermodynamic uncertainty relations (TURs) are general lower bounds on the size of fluctuations of dynamical observables. They have important consequences, one being that the precision of estimation of a current is limited by the amount of entropy pr... Read More about General upper bounds on fluctuations of trajectory observables.

Slow dynamics and nonergodicity of the bosonic quantum East model in the semiclassical limit (2023)
Journal Article
Geißler, A., & Garrahan, J. P. (2023). Slow dynamics and nonergodicity of the bosonic quantum East model in the semiclassical limit. Physical Review E, 108(3), Article 034207. https://doi.org/10.1103/PhysRevE.108.034207

We study the unitary dynamics of the bosonic quantum East model, a kinetically constrained lattice model which generalizes the quantum East model to arbitrary occupation per site. We consider the semiclassical limit of large (but finite) site occupan... Read More about Slow dynamics and nonergodicity of the bosonic quantum East model in the semiclassical limit.

Slow heterogeneous relaxation due to constraints in dual XXZ models (2023)
Journal Article
Zadnik, L., & Garrahan, J. P. (2023). Slow heterogeneous relaxation due to constraints in dual XXZ models. Physical Review B, 108(10), Article L100304. https://doi.org/10.1103/PhysRevB.108.L100304

With the aim to understand the role of the constraints in the thermalization of quantum systems, we study the dynamics of a family of kinetically constrained models arising through duality from the XXZ spin chain. We find that integrable and noninteg... Read More about Slow heterogeneous relaxation due to constraints in dual XXZ models.

Reaction-Limited Quantum Reaction-Diffusion Dynamics (2023)
Journal Article
Perfetto, G., Carollo, F., Garrahan, J. P., & Lesanovsky, I. (2023). Reaction-Limited Quantum Reaction-Diffusion Dynamics. Physical Review Letters, 130(21), Article 210402. https://doi.org/10.1103/PhysRevLett.130.210402

We consider the quantum nonequilibrium dynamics of systems where fermionic particles coherently hop on a one-dimensional lattice and are subject to dissipative processes analogous to those of classical reaction-diffusion models. Particles can either... Read More about Reaction-Limited Quantum Reaction-Diffusion Dynamics.

Stochastic strong zero modes and their dynamical manifestations (2023)
Journal Article
Klobas, K., Fendley, P., & Garrahan, J. P. (2023). Stochastic strong zero modes and their dynamical manifestations. Physical Review E, 107(4), Article L042104. https://doi.org/10.1103/PhysRevE.107.L042104

Strong zero modes (SZMs) are conserved operators localized at the edges of certain quantum spin chains, which give rise to long coherence times of edge spins. Here we define and analyze analogous operators in one-dimensional classical stochastic syst... Read More about Stochastic strong zero modes and their dynamical manifestations.

Optimal Sampling of Dynamical Large Deviations in Two Dimensions via Tensor Networks (2023)
Journal Article
Causer, L., Bañuls, M. C., & Garrahan, J. P. (2023). Optimal Sampling of Dynamical Large Deviations in Two Dimensions via Tensor Networks. Physical Review Letters, 130(14), Article 147401. https://doi.org/10.1103/PhysRevLett.130.147401

We use projected entangled-pair states (PEPS) to calculate the large deviation statistics of the dynamical activity of the two-dimensional East model, and the two-dimensional symmetric simple exclusion process (SSEP) with open boundaries, in lattices... Read More about Optimal Sampling of Dynamical Large Deviations in Two Dimensions via Tensor Networks.

Concentration Inequalities for Output Statistics of Quantum Markov Processes (2023)
Journal Article
Girotti, F., Garrahan, J. P., & Guţă, M. (2023). Concentration Inequalities for Output Statistics of Quantum Markov Processes. Annales Henri Poincaré, https://doi.org/10.1007/s00023-023-01286-1

We derive new concentration bounds for time averages of measurement outcomes in quantum Markov processes. This generalizes well-known bounds for classical Markov chains, which provide constraints on finite-time fluctuations of time-additive quantitie... Read More about Concentration Inequalities for Output Statistics of Quantum Markov Processes.

Generalized continuous Maxwell demons (2023)
Journal Article
Garrahan, J. P., & Ritort, F. (2023). Generalized continuous Maxwell demons. Physical Review E, 107(3), Article 034101. https://doi.org/10.1103/physreve.107.034101

We introduce a family of generalized continuous Maxwell demons (GCMDs) operating on idealized single-bit equilibrium devices that combine the single-measurement Szilard and the repeated measurements of the continuous Maxwell demon protocols. We deriv... Read More about Generalized continuous Maxwell demons.

Anderson and many-body localization in the presence of spatially correlated classical noise (2022)
Journal Article
Marcantoni, S., Carollo, F., Gambetta, F. M., Lesanovsky, I., Schneider, U., & Garrahan, J. P. (2022). Anderson and many-body localization in the presence of spatially correlated classical noise. Physical Review B, 106(13), Article 134211. https://doi.org/10.1103/physrevb.106.134211

We study the effect of spatially correlated classical noise on both Anderson and many-body localization of a disordered fermionic chain. By analyzing the evolution of the particle density imbalance following a quench from an initial charge density wa... Read More about Anderson and many-body localization in the presence of spatially correlated classical noise.

Slow dynamics and large deviations in classical stochastic Fredkin chains (2022)
Journal Article
Causer, L., Garrahan, J. P., & Lamacraft, A. (2022). Slow dynamics and large deviations in classical stochastic Fredkin chains. Physical Review E, 106(1), Article 014128. https://doi.org/10.1103/PhysRevE.106.014128

The Fredkin spin chain serves as an interesting theoretical example of a quantum Hamiltonian whose ground state exhibits a phase transition between three distinct phases, one of which violates the area law. Here we consider a classical stochastic ver... Read More about Slow dynamics and large deviations in classical stochastic Fredkin chains.

Random matrix theory for quantum and classical metastability in local Liouvillians (2022)
Journal Article
Li, J. L., Rose, D. C., Garrahan, J. P., & Luitz, D. J. (2022). Random matrix theory for quantum and classical metastability in local Liouvillians. Physical Review B, 105(18), Article L180201. https://doi.org/10.1103/physrevb.105.l180201

We consider the effects of strong dissipation in quantum systems with a notion of locality, which induces a hierarchy of many-body relaxation timescales as shown in [Phys. Rev. Lett. 124, 100604 (2020)]. If the strength of the dissipation varies stro... Read More about Random matrix theory for quantum and classical metastability in local Liouvillians.