English
Related papers

Related papers: Delayed Choice Lorentz Transformations on a Qubit

200 papers

We introduce a discrete-time quantum dynamics on a two-dimensional lattice that describes the evolution of a $1+1$-dimensional spin system. The underlying quantum map is constructed such that the reduced state at each time step is…

Quantum Physics · Physics 2019-02-11 I. Lesanovsky , Katarzyna Macieszczak , Juan P. Garrahan

A $\mathcal{PT}$-symmetric, non-Hermitian Hamiltonian in the $\mathcal{PT}$-unbroken regime can lead to unitary dynamics under the appropriate choice of the Hilbert space. The Hilbert space is determined by a Hamiltonian-compatible inner…

Quantum Physics · Physics 2025-03-19 Himanshu Badhani , Subhashish Banerjee , C. M. Chandrashekar

We investigate the role of quantum monitoring in the dynamical manifestations of Hamiltonian quantum chaos. Specifically, we analyze the generalized spectral form factor, defined as the survival probability of a coherent Gibbs state under…

Quantum Physics · Physics 2026-02-04 Preethi Gopalakrishnan , András Grabarits , Adolfo del Campo

We present a novel method to simulate the Lindblad equation, drawing on the relationship between Lindblad dynamics, stochastic differential equations, and Hamiltonian simulations. We derive a sequence of unitary dynamics in an enlarged…

Quantum Physics · Physics 2024-08-27 Zhiyan Ding , Xiantao Li , Lin Lin

We demonstrate the existence of a dynamical quantum phase transition (DQPT) in a dissipative collective-spin model that exhibits the boundary time crystal (BTC) phase. We initialize the system in the ground state of the Hamiltonian in…

Quantum Physics · Physics 2026-02-05 Sukrut Mondkar , Priya Ghosh , Ujjwal Sen

When an experimentalist measures a time series of qubits, the outcomes generate a classical stochastic process. We show that measurement induces high complexity in these processes in two specific senses: they are inherently unpredictable…

Quantum Physics · Physics 2020-10-14 Ariadna E. Venegas-Li , Alexandra M. Jurgens , James P. Crutchfield

We introduce the notion of a dynamical topological order parameter (DTOP) that characterises dynamical quantum phase transitions (DQPTs) occurring in the subsequent temporal evolution of "two dimensional" closed quantum systems, following a…

Statistical Mechanics · Physics 2017-07-19 Utso Bhattacharya , Amit Dutta

We show that quantum nondemolition (QND) measurements can be used to realize measurement-based imaginary time evolution. In our proposed scheme, repeated weak QND measurements are used to estimate the energy of a given Hamiltonian. Based on…

Dynamical quantum phase transitions (DQPTs) are non-equilibrium transitions characterized by the orthogonality between an initial quantum state and its time-evolved counterpart following a sudden quench. Recently, studies of this phenomenon…

Quantum Physics · Physics 2026-05-27 Kai Zhang , Chang Shu , Kai Sun

Despite its long history, a canonical formulation of quantum ergodicity that applies to general classes of quantum dynamics, including driven systems, has not been fully established. Here we introduce and study a notion of quantum…

Quantum Physics · Physics 2024-12-10 Saúl Pilatowsky-Cameo , Iman Marvian , Soonwon Choi , Wen Wei Ho

We present a quantum averaging theory (QAT) for analytically modeling unitary gate dynamics in driven quantum systems beyond the rotating-wave approximation. QAT addresses the simultaneous presence of distinct timescales by generating a…

Quantum Physics · Physics 2026-01-05 Kristian D. Barajas , Wesley C. Campbell

We develop a hybrid qubit-qumode framework for simulating quantum electrodynamics in 2+1 dimensions. In this approach, fermionic matter fields are represented by qubits, while U(1) gauge fields are encoded in continuous-variable bosonic…

Quantum Physics · Physics 2025-11-27 Victor Ale , Tommaso Rainaldi , Enrique Rico , Felix Ringer , George Siopsis

We present a systematic study of the cosmological dynamics resulting from an effective Hamiltonian, recently derived in loop quantum gravity using Thiemann's regularization and earlier obtained in loop quantum cosmology (LQC) by keeping the…

General Relativity and Quantum Cosmology · Physics 2018-04-25 Bao-Fei Li , Parampreet Singh , Anzhong Wang

We consider a quantum system periodically driven with a strength which varies slowly on the scale of the driving period. The analysis is based on a general formulation of the Floquet theory relying on the extended Hilbert space. It is shown…

Quantum Gases · Physics 2017-02-22 Viktor Novičenko , Egidijus Anisimovas , Gediminas Juzeliūnas

Non-Hermitian Hamiltonians are relevant to describe the features of a broad class of physical phenomena, ranging from photonics and atomic and molecular systems to nuclear physics and mesoscopic electronic systems. An important question…

Mesoscale and Nanoscale Physics · Physics 2021-04-21 Ygor Pará , Giandomenico Palumbo , Tommaso Macrì

The supersymmetric structure of a generalized non-Hermitian driven two-level system is demonstrated. A unitary rotation turns the Hamiltonian into a more convenient form. After decoupling a set of differential equations, the supersymmetric…

Quantum Physics · Physics 2025-10-16 Ivan A. Bocanegra-Garay , Luis M. Nieto

So far it has been shown that the quantum dynamics cannot be described as a classical Markov process unless the number of classical states is uncountably infinite. In this paper, we present a stochastic model with time-correlated noise that…

Quantum Physics · Physics 2012-04-19 Alberto Montina

Classical Hamiltonian ratchets have been recently successfully realized using cold atoms in driven optical lattices. Here we study the current rectification of the motion of a quantum particle in a periodic potential exposed to an external…

Statistical Mechanics · Physics 2007-05-23 S. Denisov , L. Morales-Molina , S. Flach

We investigate the dynamics of two-dimensional quantum spin systems under the combined effect of random unitary gates and local projective measurements. When considering steady states, a measurement-induced transition occurs between two…

Statistical Mechanics · Physics 2020-10-16 Xhek Turkeshi , Rosario Fazio , Marcello Dalmonte

Dynamic equations concerning physical expectation values have been examined in terms of the real Hilbert space approach to quantum mechanics. The considered cases involve complex wave functions, as well as quaternionic wave functions. The…

Quantum Physics · Physics 2025-09-19 Sergio Giardino