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Related papers: Quantum Thermal State Preparation

200 papers

Quantum Gibbs state sampling algorithms generally suffer from either scaling exponentially with system size or requiring specific knowledge of spectral properties \textit{a priori}. Also, these algorithms require a large overhead of bath or…

Quantum Physics · Physics 2020-09-02 Jeffrey Cohn , Khadijeh Sona Najafi , Forest Yang , Barbara Jones , James K. Freericks

Classical Markov Chain Monte Carlo methods have been essential for simulating statistical physical systems and have proven well applicable to other systems with many degrees of freedom. Motivated by the statistical physics origins, Chen,…

Quantum Physics · Physics 2026-01-26 András Gilyén , Chi-Fang Chen , Joao F. Doriguello , Michael J. Kastoryano

Szegedy's quantum walk gives a generic quadratic speedup for reversible classical Markov chains, but extending this mechanism to quantum Gibbs sampling has remained challenging beyond special cases. We present a walk-free quantum algorithm…

Quantum Physics · Physics 2026-04-28 Jiaqi Leng , Jiaqing Jiang , Lin Lin

The phase diagram of strong interactions in nature at finite temperature and chemical potential remains largely unexplored theoretically due to inadequacy of Monte-Carlo-based computational techniques in overcoming a sign problem. Quantum…

High Energy Physics - Lattice · Physics 2024-03-05 Zohreh Davoudi , Niklas Mueller , Connor Powers

We consider two related tasks: (a) estimating a parameterisation of a given Gibbs state and expectation values of Lipschitz observables on this state; and (b) learning the expectation values of local observables within a thermal or quantum…

Quantum Physics · Physics 2024-09-09 Emilio Onorati , Cambyse Rouzé , Daniel Stilck França , James D. Watson

Preparing quantum thermal states on a quantum computer is in general a difficult task. We provide a procedure to prepare a thermal state on a quantum computer with a logarithmic depth circuit of local quantum channels assuming that the…

Quantum Physics · Physics 2019-02-13 Fernando G. S. L. Brandao , Michael J. Kastoryano

We present a holographic quantum simulation algorithm to variationally prepare thermal states of $d$-dimensional interacting quantum many-body systems, using only enough hardware qubits to represent a ($d$-1)-dimensional cross-section. This…

Quantum Physics · Physics 2022-10-17 Yuxuan Zhang , Shahin Jahanbani , Daoheng Niu , Reza Haghshenas , Andrew C. Potter

We propose a general-purpose quantum algorithm for preparing ground states of quantum Hamiltonians from a given trial state. The algorithm is based on techniques recently developed in the context of solving the quantum linear systems…

Quantum Physics · Physics 2018-02-05 Yimin Ge , Jordi Tura , J. Ignacio Cirac

The Gibbs canonical state, as a maximum entropy density matrix, represents a quantum system in equilibrium with a thermostat. This state plays an essential role in thermodynamics and serves as the initial condition for nonequilibrium…

Quantum Physics · Physics 2016-06-22 Denys I. Bondar , Andre G. Campos , Renan Cabrera , Herschel A. Rabitz

We present a general protocol for estimating $M$ observables from only $\mathcal{O}(\log (M)/\varepsilon^2)$ copies of a Gibbs state whose Hamiltonian is accessible. The protocol uses single-copy, nonadaptive measurements and uses a total…

Quantum Physics · Physics 2026-03-18 Chi-Fang Chen , András Gilyén

Simulating thermal-equilibrium properties at finite temperature is crucial for studying quantum many-body systems. Quantum computers are expected to enable us to simulate large systems at finite temperatures, overcoming challenges faced by…

Thermal properties of nanomaterials are crucial to not only improving our fundamental understanding of condensed matter systems, but also to developing novel materials for applications spanning research and industry. Since quantum effects…

Quantum Physics · Physics 2022-08-26 Connor Powers , Lindsay Bassman Oftelie , Daan Camps , Wibe A. de Jong

Calculations at finite temperatures are fundamental in different scientific fields, from nuclear physics to condensed matter. Evolution in imaginary time is a prominent classical technique for preparing thermal states of quantum systems. We…

Quantum Physics · Physics 2023-06-30 Francesco Turro

Preparing the ground states of a many-body system is essential for evaluating physical quantities and determining the properties of materials. This work provides a quantum ground state preparation scheme with shallow variational warm-start…

Quantum Physics · Physics 2023-03-21 Youle Wang , Chenghong Zhu , Mingrui Jing , Xin Wang

Efficient simulation of a quantum system generally relies on structural properties of the quantum state. Motivated by the recent results by Bakshi et al. on the sudden death of entanglement in high-temperature Gibbs states of quantum spin…

Quantum Physics · Physics 2026-01-21 Akshar Ramkumar , Yiyi Cai , Yu Tong , Jiaqing Jiang

Electronic excited states are central to a vast array of physical and chemical phenomena, yet accurate and efficient methods for preparing them on quantum devices remain challenging and comparatively underexplored. We introduce a general…

Quantum Physics · Physics 2026-02-02 Hao-En Li , Lin Lin

Quantum computers can efficiently simulate Lindbladian dynamics, enabling powerful applications in open system simulation, thermal and ground-state preparation, autonomous quantum error correction, dissipative engineering, and more. Despite…

Quantum Physics · Physics 2025-10-20 Wenjun Yu , Xiaogang Li , Qi Zhao , Xiao Yuan

The Markov Chain Monte Carlo method is at the heart of efficient approximation schemes for a wide range of problems in combinatorial enumeration and statistical physics. It is therefore very natural and important to determine whether…

Quantum Physics · Physics 2009-11-13 Pawel Wocjan , Anura Abeyesinghe

The preparation of quantum Gibbs state is an essential part of quantum computation and has wide-ranging applications in various areas, including quantum simulation, quantum optimization, and quantum machine learning. In this paper, we…

Quantum Physics · Physics 2021-11-23 Youle Wang , Guangxi Li , Xin Wang

Quantum annealers are emerging as programmable, dynamical experimental platforms for probing strongly correlated spin systems. Yet key thermal assumptions, chiefly a Gibbs-distributed output ensemble, remain unverified in the large-scale…

Quantum Physics · Physics 2025-12-04 George Grattan , Pratik Sathe , Cristiano Nisoli