974 citations · 7.3k across the 94 of their papers we have counts for
43 papers · 1 filter
Classification of same-gate quantum circuits and their space-time symmetries with application to the level-spacing distribution
Urban Duh, Marko Znidaric
We study Floquet systems with translationally invariant nearest-neighbor 2-site gates. Depending on the order in which the gates are applied on an N-site system with periodic bound…
Phantom relaxation rate of the average purity evolution in random circuits due to Jordan non-Hermitian skin effect and magic sums
Marko Znidaric
Phantom relaxation is relaxation with a rate that is not given by a finite spectral gap. Studying the average purity dynamics in a staircase random Haar circuit and the spectral de…
Two-step relaxation in local many-body Floquet systems
Marko Znidaric
We want to understand how relaxation process from an initial non-generic state proceeds towards a long-time typical state reached under unitary quantum evolution. One would expect…
Purity decay rate in random circuits with different configurations of gates
Jaš Bensa, Marko Žnidarič
We study purity decay -- a measure of bipartite entanglement -- in a chain of qubits under the action of various geometries of nearest-neighbor random two-site unitary gates. W…
Solvable non-Hermitian skin effect in many-body unitary dynamics
Marko Znidaric
We study unitary evolution of bipartite entanglement in a circuit with nearest-neighbor random gates. Deriving a compact non-unitary description of purity dynamics on qudits we fin…
Two-step phantom relaxation of out-of-time-ordered correlations in random circuits
Jas Bensa, Marko Znidaric
We study out-of-time-ordered correlation (OTOC) functions in various random quantum circuits and show that the average dynamics is governed by a Markovian propagator. This is then…
Fastest local entanglement scrambler, multistage thermalization, and a non-Hermitian phantom
Jas Bensa, Marko Znidaric
We study random quantum circuits and their rate of producing bipartite entanglement, specifically with respect to the choice of 2-qubit gates and the order (protocol) in which thes…
Dissipative remote-state preparation in an interacting medium
Marko Znidaric
Standard quantum state preparation methods work by preparing a required state locally and then distributing it to a distant location by a free-space propagation. We instead study p…
Geometry of local quantum dissipation and fundamental limits to local cooling
Marko Znidaric
We geometrically characterize one-qubit dissipators of a Lindblad type. An efficient parametrization in terms of 6 linear parameters opens the way to various optimizations with loc…
Translationally invariant conservation laws of local Lindblad equations
Marko Znidaric, Giuliano Benenti, Giulio Casati
We study the conditions under which one can conserve local translationally invariant operators by local translationally invariant Lindblad equations in one-dimensional rings of spi…
Eigenvalue statistics as indicator of integrability of non-equilibrium density operators
Tomaz Prosen, Marko Znidaric
We propose to quantify the complexity of non-equilibrium steady state density operators, as well as of long-lived Liouvillian decay modes, in terms of level spacing distribution of…
A universal set of qubit quantum channels
Daniel Braun, Olivier Giraud, Ion Nechita +2
We investigate the set of quantum channels acting on a single qubit. We provide an alternative, compact generalization of the Fujiwara-Algoet conditions for complete positivity to…
Entanglement in stationary nonequilibrium states at high energies
Marko Znidaric
In recent years it has been found that quantum systems can posses entanglement in equilibrium thermal states provided temperature is low enough. In the present work we explore a po…
Subsystem dynamics under random Hamiltonian evolution
Vinayak, Marko Znidaric
We study time evolution of a subsystem's density matrix under unitary evolution, generated by a sufficiently complex, say quantum chaotic, Hamiltonian, modeled by a random matrix.…
Transport properties of a boundary-driven one-dimensional gas of spinless fermions
Marko Znidaric, Bojan Zunkovic, Tomaz Prosen
We analytically study a system of spinless fermions driven at the boundary with an oscillating chemical potential. Various transport regimes can be observed: at zero driving freque…
Non-Markovian behavior of small and large complex quantum systems
Marko Znidaric, Carlos Pineda, Ignacio Garcia-Mata
The channel induced by a complex system interacting strongly with a qubit is calculated exactly under the assumption of randomness of its eigenvectors. The resulting channel is rep…
Quantum transport in one-dimensional systems via a master equation approach: Numerics and an exact solution
Marko Znidaric
We discuss recent findings about properties of quantum nonequilibrium steady states. In particular we focus on transport properties. It is shown that the time dependent density mat…
Thermalization and ergodicity in many-body open quantum systems
Marko Znidaric, Tomaz Prosen, Giuliano Benenti +2
We study thermalization in many-body quantum systems locally coupled to an external bath. It is shown that quantum chaotic systems do thermalize, that is, they exhibit relaxation t…
Quantum circuit for three-qubit random states
Olivier Giraud, Marko Znidaric, Bertrand Georgeot
We explicitly construct a quantum circuit which exactly generates random three-qubit states. The optimal circuit consists of three CNOT gates and fifteen single qubit elementary ro…
Matrix product simulations of non-equilibrium steady states of quantum spin chains
Tomaz Prosen, Marko Znidaric
Time-dependent density matrix renormalization group method with a matrix product ansatz is employed for explicit computation of non-equilibrium steady state density operators of se…
Exact convergence times for generation of random bipartite entanglement
Marko Znidaric
We calculate exact convergence times to reach random bipartite entanglement for various random protocols. The eigenproblem of a Markovian chain governing the process is mapped to a…
Complexity of thermal states in quantum spin chains
Marko Znidaric, Tomaz Prosen, Iztok Pizorn
We study quantum correlations and complexity of simulation, characterized by quantum mutual information and entanglement entropy in operator space respectively, for thermal states…
Initial-state randomness as a universal source of decoherence
Marko Znidaric
We study time evolution of entanglement between two qubits, which are part of a larger system, after starting from a random initial product state. We show that, due to randomness i…
How many CNOT gates does it take to generate a three-qubit state ?
Marko Znidaric, Olivier Giraud, Bertrand Georgeot
The number of two-qubit gates required to transform deterministically a three-qubit pure quantum state into another is discussed. We show that any state can be prepared from a prod…