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Related papers: Fast quantum imaginary time evolution

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Imaginary-time evolution is fundamental for analyzing quantum many-body systems, yet classical simulation requires exponentially growing resources in both system size and evolution time. While quantum approaches reduce the system-size…

Quantum Physics · Physics 2025-12-12 Lei Zhang , Jizhe Lai , Xian Wu , Xin Wang

Quantum imaginary-time evolution (QITE) is a fundamental framework for preparing ground and thermal states, yet its computational cost scales significantly with the evolution duration $\tau$. Reducing this duration is critical for practical…

Quantum Physics · Physics 2026-04-21 Yumeng Zeng , Jeongrak Son , Mile Gu , Xiao Yuan

Quantum simulation on emerging quantum hardware is a topic of intense interest. While many studies focus on computing ground state properties or simulating unitary dynamics of closed systems, open quantum systems are an interesting target…

Quantum Physics · Physics 2022-03-21 Hirsh Kamakari , Shi-Ning Sun , Mario Motta , Austin J. Minnich

Imaginary-time evolution (ITE) on a quantum computer is a promising formalism for obtaining the ground state of a quantum system. As a kind of it, the probabilistic ITE (PITE) takes advantage of measurements to implement the nonunitary…

Quantum Physics · Physics 2022-08-15 Taichi Kosugi , Yusuke Nishiya , Hirofumi Nishi , Yu-ichiro Matsushita

In this work we propose an approach for implementing time-evolution of a quantum system using product formulas. The quantum algorithms we develop have provably better scaling (in terms of gate complexity and circuit depth) than a naive…

Evolution in imaginary time is a prominent technique for finding the ground state of quantum many-body systems, and the heart of a number of numerical methods that have been used with great success in quantum chemistry, condensed matter and…

The imaginary-time evolution of quantum states is integral to various fields, ranging from natural sciences to classical optimization or machine learning. Since simulating quantum imaginary-time evolution generally requires storing an…

Quantum Physics · Physics 2024-01-17 Julien Gacon , Christa Zoufal , Giuseppe Carleo , Stefan Woerner

Many current and near-future applications of quantum computing utilise parametric families of quantum circuits and variational methods to find optimal values for these parameters. Solving a quantum computational problem with such…

Quantum Physics · Physics 2025-08-05 Tobias Hartung , Karl Jansen

Variational Quantum Imaginary Time Evolution (VQITE) is a leading technique for ground state preparation on quantum computers. A significant computational challenge of VQITE is the determination of the quantum geometric tensor. We show that…

Quantum Physics · Physics 2024-09-19 Aeishah Ameera Anuar , Francois Jamet , Fabio Gironella , Fedor Simkovic , Riccardo Rossi

We study the Schwinger model at finite-temperature regime using a quantum-classical hybrid algorithm. The preparation of thermal state on quantum circuit presents significant challenges. To address this, we adopt the Thermal Pure Quantum…

High Energy Physics - Lattice · Physics 2023-11-21 Juan W. Pedersen , Etsuko Itou , Rong-Yang Sun , Seiji Yunoki

Ground-state preparation is an important task in quantum computation. The probabilistic imaginary-time evolution (PITE) method is a promising candidate for preparing the ground state of the Hamiltonian, which comprises a single ancilla…

Quantum Physics · Physics 2023-11-08 Hirofumi Nishi , Koki Hamada , Yusuke Nishiya , Taichi Kosugi , Yu-ichiro Matsushita

We propose an imaginary time equivalent of the well-established Pauli gadget primitive for Trotter-decomposed real time evolution, using mid-circuit measurements on a single ancilla qubit. Imaginary time evolution (ITE) is widely used for…

Quantum Physics · Physics 2023-10-31 Chiara Leadbeater , Nathan Fitzpatrick , David Muñoz Ramo , Alex J. W. Thom

We develop a resource efficient step-merged quantum imaginary time evolution approach (smQITE) to solve for the ground state of a Hamiltonian on quantum computers. This heuristic method features a fixed shallow quantum circuit depth along…

Computational Physics · Physics 2020-09-21 Niladri Gomes , Feng Zhang , Noah F. Berthusen , Cai-Zhuang Wang , Kai-Ming Ho , Peter P. Orth , Yongxin Yao

We introduce a constructive method for mapping non-unitary dynamics to a weighted set of unitary operations. We utilize this construction to derive a new correspondence between real and imaginary time, which we term Imaginary Time Quantum…

Quantum Physics · Physics 2024-09-11 Jacob M. Leamer , Alicia B. Magann , Denys I. Bondar , Gerard McCaul

The time evolution operator plays a crucial role in the precise computation of chemical experiments on quantum computers and holds immense promise for advancing the fields of physical and computer sciences, with applications spanning…

Quantum computing promises the ability to compute properties of quantum systems exponentially faster than classical computers. Quantum advantage is achieved when a practical problem is solved more efficiently on a quantum computer than on a…

Quantum Physics · Physics 2025-12-03 William A. Simon , Peter J. Love

Imaginary time evolution is a powerful tool for studying quantum systems. While it is possible to simulate with a classical computer, the time and memory requirements generally scale exponentially with the system size. Conversely, quantum…

Quantum Physics · Physics 2019-09-17 Sam McArdle , Tyson Jones , Suguru Endo , Ying Li , Simon Benjamin , Xiao Yuan

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

Efficiently preparing approximate ground-states of large, strongly correlated systems on quantum hardware is challenging and yet nature is innately adept at this. This has motivated the study of thermodynamically inspired approaches to…

We present quantum algorithms for the simulation of quantum systems in one spatial dimension, which result in quantum speedups that range from superpolynomial to polynomial. We first describe a method to simulate the evolution of the…

Quantum Physics · Physics 2016-08-09 Rolando D. Somma