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Related papers: Sudden switching in qubits

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As physical systems, qubits must evolve from input to output state. We describe a simple scheme in which the effect of a quantum gate is described by the action of an effective Hamiltonian acting for some characteristic time. This model…

Quantum Physics · Physics 2026-04-21 M. P. Vaughan

The (Loschmidt) overlap between the state at different times after a quantum quench is attracting increasing interest, as it was recently shown that in the thermodynamic limit its logarithm per unit of length has a non-analytic behavior if…

Statistical Mechanics · Physics 2013-09-09 Maurizio Fagotti

The study of quantum resonances in the chaotic atom-optics kicked rotor system is of interest from two different perspectives. In quantum chaos, it marks out the regime of resonant quantum dynamics in which the atomic cloud displays…

Quantum Physics · Physics 2019-08-16 Kush Mohan Mittal , M. S. Santhanam

We investigate theoretically the dynamics of the system that consists of a cascade three-level emitter interacting with a single-mode resonator in the deep-strong-coupling regime. We show that the dynamical evolution of the system can only…

Quantum Physics · Physics 2018-11-21 Li-Li Zheng , Qian Bin , Zhi-Ming Zhan , Sha Li , Xin-You Lü , Ying Wu

Recently, the dynamics of quantum systems that involve both unitary evolution and quantum measurements have attracted attention due to the exotic phenomenon of measurement-induced phase transitions. The latter refers to a sudden change in a…

Quantum Physics · Physics 2025-06-23 Ryotaro Suzuki , Jonas Haferkamp , Jens Eisert , Philippe Faist

An effective Hamiltonian describing interaction between generic "fast" and a "slow" systems is obtained in the strong interaction limit. The result is applied for studying the effect of quantum phase transition as a bifurcation of the…

Quantum Physics · Physics 2009-11-13 Isabel Sainz , Andrei B. Klimov , Luis Roa

Entanglement evolution in high dimensional bipartite systems under dissipation is studied. Discontinuities for the time derivative of the lower bound of entanglement of formation is found depending on the initial conditions for entangled…

Quantum Physics · Physics 2008-09-12 F. Lastra , G. Romero , C. E. López , M. França Santos , J. C. Retamal

We explore quantum phase transitions using two probes of quantum chaos: out-of-time-order correlators (OTOCs) and the $r$-parameter obtained from the level spacing statistics. In particular, we address $p$-spin models associated with…

High Energy Physics - Theory · Physics 2021-09-01 Kyoung-Bum Huh , Kazuki Ikeda , Viktor Jahnke , Keun-Young Kim

Over the last few years it was pointed out that certain observables of time-evolving quantum systems may have singularities at certain moments in time, mimicking the singularities physical systems have when undergoing phase transitions.…

Statistical Mechanics · Physics 2019-09-11 V. Gurarie

We analyze the consequences of iterative measurement-induced nonlinearity on the dynamical behavior of qubits. We present a one-qubit scheme where the equation governing the time evolution is a complex-valued nonlinear map with one complex…

Quantum Physics · Physics 2007-05-23 T. Kiss , I. Jex , G. Alber , S. Vymetal

Temporal evolution of a comoving qubit coupled to a scalar field in de Sitter space is studied with an emphasis on reliable extraction of late-time behaviour. The phenomenon of critical slowing down is observed if the effective mass is…

High Energy Physics - Theory · Physics 2020-02-17 Greg Kaplanek , C. P. Burgess

We characterize good clocks, which are naturally subject to fluctuations, in statistical terms. We also obtain the master equation that governs the evolution of quantum systems according to these clocks and find its general solution. This…

Quantum Physics · Physics 2009-10-31 Inigo L. Egusquiza , Luis J. Garay , Jose M. Raya

Multiple quantum experiments are used to resolve broad peaks in nuclear magnetic resonance spectra of quadrupolar nuclei. In this work, we study phase cycling of radio frequency pulses in a single quantum satellite transition magic angle…

Quantum Physics · Physics 2014-01-30 Peter Malavé

Evolutionary dynamics provides an iconic relationship --- the periodic frequency of a game is determined by the payoff matrix of the game. This paper reports the first experimental evidence to demonstrate this relationship. Evidence comes…

Adaptation and Self-Organizing Systems · Physics 2015-03-20 Bin Xu , Shuang Wang , Zhijian Wang

The spectral properties of interacting strongly chaotic systems are investigated for growing interaction strength. A very sensitive transition from Poisson statistics to that of random matrix theory is found. We introduce a new random…

It has been recently pointed out [V. Giovanetti, S. Lloyd, and L. Maccone, Europhys. Lett., {\bf 62} pp. 615-621 (2003)] that, for certain classes of states, quantum entanglement enhances the "speed" of evolution of composite quantum…

Quantum Physics · Physics 2016-09-08 J. Batle , M. Casas , A. Plastino , A. R. Plastino

The coherent control of small quantum system is considered. For a two-level system coupled to an arbitrary bath we consider a pulse of finite duration. We derive the leading and the next-leading order corrections to the evolution operator…

Quantum Physics · Physics 2008-03-11 S. Pasini , T. Fischer , P. Karbach , G. S. Uhrig

The mechanism governing the evolution of controlled quantum systems is often obscured, making their dynamics hard to interpret. Mitra and Rabitz {[Phys. Rev. A 67, 033407 (2003)]} define mechanism via a perturbative expansion of pathways…

Quantum Physics · Physics 2024-10-02 Erez Abrams

This paper describes the dynamics of a quantum two-level system (qubit) under the influence of an environment modeled by an ensemble of random matrices. In distinction to earlier work, we consider here separable couplings and focus on a…

Quantum Physics · Physics 2015-06-19 M. Carrera , T. Gorin , T. H. Seligman

We propose to analyse the statistical properties of a sequence of vectors using the spectrum of the associated Gram matrix. Such sequences arise e.g. by the repeated action of a deterministic kicked quantum dynamics on an initial condition…

Mathematical Physics · Physics 2007-05-23 Mieke De Cock , Mark Fannes , Pascal Spincemaille