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Related papers: Efficiency, Curvature, and Complexity of Quantum E…

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The rapid development of reliable Quantum Processing Units (QPU) opens up novel computational opportunities for machine learning. Here, we introduce a procedure for measuring the similarity between graph-structured data, based on the…

Quantum Physics · Physics 2021-09-29 Louis-Paul Henry , Slimane Thabet , Constantin Dalyac , Loïc Henriet

We study the quantum evolution of a non-Hermitian qubit realized as a submanifold of a dissipative superconducting transmon circuit. Real-time tuning of the system parameters to encircle an exceptional point results in non-reciprocal…

Quantum Physics · Physics 2022-04-27 Maryam Abbasi , Weijian Chen , Mahdi Naghiloo , Yogesh N. Joglekar , Kater W. Murch

Many optimally scaling quantum simulation algorithms employ controlled time evolution of the Hamiltonian, which is typically the major bottleneck for their efficient implementation. This work establishes a compression protocol for encoding…

Quantum Physics · Physics 2026-04-09 Erenay Karacan

Quantum complexity is a measure of the minimal number of elementary operations required to approximately prepare a given state or unitary channel. Recently, this concept has found applications beyond quantum computing -- in studying the…

Quantum Physics · Physics 2025-01-22 Michał Oszmaniec , Marcin Kotowski , Michał Horodecki , Nicholas Hunter-Jones

The evolution of an open system is usually associated with the interaction of the system with an environment. A new method to study the open-type system evolution of a qubit (two-level atom) state is established. This evolution is…

An enduring challenge in computer science is reducing the runtime required to solve computational problems. Quantum computing has attracted significant attention due to its potential to deliver asymptotically faster solutions to certain…

Quantum Physics · Physics 2025-03-25 Mischa P. Woods

The traditional quantum speed limits are not attainable for many physical processes, as they tend to be loose and fail to determine the exact time taken by quantum systems to evolve. To address this, we derive exact quantum speed limits for…

Quantum Physics · Physics 2023-08-30 Arun K. Pati , Brij Mohan , Sahil , Samuel L. Braunstein

A complete theoretical treatment in many problems relevant to physics, chemistry, and biology requires considering the action of the environment over the system of interest. Usually the environment involves a relatively large number of…

Quantum Physics · Physics 2010-03-03 A. S. Sanz , F. Borondo

Although quantum control typically relies on greedy (local) optimization, traps (irregular critical points) in the control landscape can make optimization hard by foiling local search strategies. We demonstrate the failure of greedy…

Quantum Physics · Physics 2014-09-17 Ehsan Zahedinejad , Sophie Schirmer , Barry C. Sanders

Continuous-time quantum walk describes the propagation of a quantum particle (or an excitation) evolving continuously in time on a graph. As such, it provides a natural framework for modeling transport processes, e.g., in light-harvesting…

Quantum Physics · Physics 2021-08-02 Luca Razzoli , Matteo G. A. Paris , Paolo Bordone

To overcome the fast oscillatory behavior of correlation functions for extracting scattering phase shift in real-time quantum simulations encountered in Ref.\cite{Guo:2026qkx}, we propose and test two solutions in the present work. One is…

Quantum Physics · Physics 2026-04-02 Peng Guo , Paul LeVan , Frank X. Lee , Yong Zhao

Non-Markovian open quantum systems represent the most general dynamics when the quantum system is coupled with a bath environment. The quantum dynamics arising from many important applications are non-Markovian. Although for special cases,…

Quantum Physics · Physics 2023-03-01 Xiantao Li , Chunhao Wang

Stability and instability of quantum evolution are studied in the interaction between a two-level atom with photon recoil and a quantized field mode in an ideal cavity, the basic model of cavity quantum electrodynamics (QED). It is shown…

Quantum Physics · Physics 2009-11-11 S. V. Prants , M. Yu. Uleysky , V. Yu. Argonov

Studies have shown that the Hilbert spaces of non-Hermitian systems require nontrivial metrics. Here, we demonstrate how evolution dimensions, in addition to time, can emerge naturally from a geometric formalism. Specifically, in this…

Quantum Physics · Physics 2024-03-13 Chia-Yi Ju , Adam Miranowicz , Yueh-Nan Chen , Guang-Yin Chen , Franco Nori

The number of defects which are generated on crossing a quantum phase transition can be minimized by choosing properly designed time-dependent pulses. In this work we determine what are the ultimate limits of this optimization. We discuss…

Other Condensed Matter · Physics 2015-05-20 T. Caneva , T. Calarco , R. Fazio , G. E. Santoro , S. Montangero

The time development of equal-time correlation functions in quantum mechanics and quantum field theory is described by an exact evolution equation for generating functionals. This permits a comparison between classical and quantum evolution…

High Energy Physics - Theory · Physics 2009-10-30 C. Wetterich

We present a simple formalism describing evolution of a qubit in the process of its measurement in a circuit QED setup. When a phase-sensitive amplifier is used, the evolution depends on only one output quadrature, and the formalism is the…

Quantum Physics · Physics 2012-05-11 Alexander N. Korotkov

We present a geometric perspective on how to quantify the bending and the twisting of quantum curves traced by state vectors evolving under nonstationary Hamiltonians. Specifically, relying on the existing geometric viewpoint for stationary…

Quantum Physics · Physics 2024-05-31 Paul M. Alsing , Carlo Cafaro

We study the time evolution of a PT-symmetric, non-Hermitian quantum system for which the associated phase space is compact. We focus on the simplest non-trivial example of such a Hamiltonian, which is linear in the angular momentum…

Quantum Physics · Physics 2021-08-18 Iván F. Valtierra , Mario Gaeta , Adrian Ortega , Thomas Gorin

We propose a new variational quantum algorithm, which we refer to as TIMES-ADAPT, that prepares time-evolved states in a low-energy or symmetric subspace of a time-independent Hamiltonian on a quantum computer. Using a specially trained…