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Related papers: Quantum Thermal State Preparation

200 papers

Preparing the ground state of a system is an important task in physics. We propose a quantum algorithm for preparing the ground state of a physical system that can be simulated on a quantum computer. The system is coupled to an ancillary…

Quantum Physics · Physics 2018-05-14 Hefeng Wang

Quantum computers have a potential for solving quantum chemistry problems with higher accuracy than classical computers. Quantum computing quantum Monte Carlo (QC-QMC) is a QMC with a trial state prepared in quantum circuit, which is…

Quantum Physics · Physics 2024-06-07 Shu Kanno , Hajime Nakamura , Takao Kobayashi , Shigeki Gocho , Miho Hatanaka , Naoki Yamamoto , Qi Gao

We show that thermal states of local Hamiltonians are separable above a constant temperature. Specifically, for a local Hamiltonian $H$ on a graph with degree $\mathfrak{d}$, its Gibbs state at inverse temperature $\beta$, denoted by $\rho…

Quantum Physics · Physics 2025-02-25 Ainesh Bakshi , Allen Liu , Ankur Moitra , Ewin Tang

Drawing independent samples from high-dimensional probability distributions represents the major computational bottleneck for modern algorithms, including powerful machine learning frameworks such as deep learning. The quest for discovering…

Quantum Physics · Physics 2022-10-13 Marc Vuffray , Carleton Coffrin , Yaroslav A. Kharkov , Andrey Y. Lokhov

Finding the ground state of a Hamiltonian system is of great significance in many-body quantum physics and quantum chemistry. We propose an improved iterative quantum algorithm to prepare the ground state of a Hamiltonian. The crucial point…

Quantum Physics · Physics 2022-10-25 Jin-Min Liang , Qiao-Qiao Lv , Shu-Qian Shen , Ming Li , Zhi-Xi Wang , Shao-Ming Fei

Quantum thermalization in contemporary quantum devices, in particular quantum computers, has recently attracted significant theoretical interest. Unusual thermalization processes, such as the Quantum Mpemba Effect (QME), have been explored…

Quantum Physics · Physics 2024-12-05 Marc Espinosa Edo , Lian-Ao Wu

We show how to obtain perfect samples from a quantum Gibbs state on a quantum computer. To do so, we adapt one of the `Coupling from the Past'-algorithms proposed by Propp and Wilson. The algorithm has a probabilistic run-time and produces…

Quantum Physics · Physics 2018-08-15 Daniel Stilck França

This paper discusses a classical simulation to compute the partition function (or free energy) of generic one-dimensional quantum many-body systems. Many numerical methods have previously been developed to approximately solve…

Quantum Physics · Physics 2018-07-24 Tomotaka Kuwahara , Keiji Saito

Measurement-based quantum computation utilizes an initial entangled resource state and proceeds with subsequent single-qubit measurements. It is implicitly assumed that the interactions between qubits can be switched off so that the…

Quantum Physics · Physics 2011-08-08 Ying Li , Daniel E. Browne , Leong Chuan Kwek , Robert Raussendorf , Tzu-Chieh Wei

We present an efficient quantum algorithm for preparing a pure state on a quantum computer, where the quantum state corresponds to that of a molecular system with a given number $m$ of electrons occupying a given number $n$ of spin…

Quantum Physics · Physics 2009-05-01 Hefeng Wang , S. Ashhab , Franco Nori

Many simulation tasks require that one first prepare a system's Gibbs state. We present a family of quantum circuits for variational preparation of thermal Gibbs states on a quantum computer; we call them the thermal multi-scale…

Quantum Physics · Physics 2022-11-01 Troy J. Sewell , Christopher David White , Brian Swingle

The properties of strongly-coupled lattice gauge theories at finite density as well as in real time have largely eluded first-principles studies on the lattice. This is due to the failure of importance sampling for systems with a complex…

High Energy Physics - Lattice · Physics 2025-08-20 Michael Fromm , Owe Philipsen , Michael Spannowsky , Christopher Winterowd

The dual tasks of quantum Hamiltonian learning and quantum Gibbs sampling are relevant to many important problems in physics and chemistry. In the low temperature regime, algorithms for these tasks often suffer from intractabilities, for…

We study the problem of learning the Hamiltonian of a quantum many-body system given samples from its Gibbs (thermal) state. The classical analog of this problem, known as learning graphical models or Boltzmann machines, is a well-studied…

Quantum Physics · Physics 2021-05-26 Anurag Anshu , Srinivasan Arunachalam , Tomotaka Kuwahara , Mehdi Soleimanifar

A measurement-based quantum computer could consist of a local-gapped Hamiltonian system, whose thermal states --at sufficiently low temperature-- are universal resources for the computation. Initialization of the computer would correspond…

Quantum Physics · Physics 2015-06-18 G. H. Aguilar , T. Kolb , D. Cavalcanti , L. Aolita , R. Chaves , S. P. Walborn , P. H. Souto Ribeiro

We develop a rigorous system-agnostic method to predict quantum thermalization in an overwhelming fraction of accessible pure states in a many-body system, entirely in terms of certain out-of-time-ordered correlators of few-body…

Quantum Physics · Physics 2026-04-06 Amit Vikram

We establish new theoretical results demonstrating the efficiency and robustness of system bath interaction models for quantum thermal and ground state preparation. Unlike prior analyses, which typically relies on the Lindblad limit and…

Quantum Physics · Physics 2026-02-17 Ke Wang , Zhiyan Ding

Producing quantum states at random has become increasingly important in modern quantum science, with applications both theoretical and practical. In particular, ensembles of such randomly-distributed, but pure, quantum states underly our…

We extend Quantum Computing Quantum Monte Carlo (QCQMC) beyond ground-state energy estimation by systematically constructing the quantum circuits used for state preparation. Replacing the original Variational Quantum Eigensolver (VQE)…

Quantum dynamics can be analyzed via the structure of energy eigenstates. However, in the many-body setting, preparing eigenstates associated with finite temperatures requires time scaling exponentially with system size. In this work we…

Quantum Physics · Physics 2024-07-11 Samuel J. Garratt , Soonwon Choi