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Related papers: Understanding Quantum Imaginary Time Evolution and…

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Imaginary time evolution is a powerful tool applied in quantum physics, while existing classical algorithms for simulating imaginary time evolution suffer high computational complexity as the quantum systems become larger and more complex.…

Quantum Physics · Physics 2022-10-12 Hao-Nan Xie , Shi-Jie Wei , Fan Yang , Zheng-An Wang , Chi-Tong Chen , Heng Fan , Gui-Lu Long

Quantum imaginary time evolution (QITE) algorithm is one of the most promising variational quantum algorithms (VQAs), bridging the current era of Noisy Intermediate-Scale Quantum devices and the future of fully fault-tolerant quantum…

Quantum Physics · Physics 2025-10-28 Min Chen , Bingzhi Zhang , Quntao Zhuang , Junyu Liu

In quantum adiabatic evolution algorithms, the quantum computer follows the ground state of a slowly varying Hamiltonian. The ground state of the initial Hamiltonian is easy to construct; the ground state of the final Hamiltonian encodes…

Quantum Physics · Physics 2007-05-23 Edward Farhi , Jeffrey Goldstone , Sam Gutmann

Developing scalable quantum algorithms to study finite-temperature physics of quantum many-body systems has attracted considerable interest due to recent advancements in quantum hardware. However, such algorithms in their present form…

Quantum imaginary-time evolution (QITE) is a promising tool to prepare thermal or ground states of Hamiltonians, as convergence is guaranteed when the evolved state overlaps with the ground state. However, its implementation using a a…

Quantum Physics · Physics 2025-01-20 Ioannis Kolotouros , David Joseph , Anand Kumar Narayanan

The accurate computation of Hamiltonian ground, excited, and thermal states on quantum computers stands to impact many problems in the physical and computer sciences, from quantum simulation to machine learning. Given the challenges posed…

In this work we present a detailed analysis of variational quantum phase estimation (VQPE), a method based on real-time evolution for ground and excited state estimation on near-term hardware. We derive the theoretical ground on which the…

Imaginary-time evolution, an important technique in tensor network and quantum Monte Carlo algorithms on classical computers, has recently been adapted to quantum computing. In this study, we focus on probabilistic imaginary-time evolution…

Strongly Correlated Electrons · Physics 2025-11-27 Satoshi Ejima , Kazuhiro Seki , Benedikt Fauseweh , Seiji Yunoki

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

Quantum imaginary time evolution (QITE) is one of the promising candidates for finding eigenvalues and eigenstates of a Hamiltonian. However, the original QITE proposal [Nat. Phys. 16, 205-210 (2020)], which approximates the imaginary time…

Quantum Physics · Physics 2023-09-27 Yifei Huang , Yuguo Shao , Weiluo Ren , Jinzhao Sun , Dingshun Lv

Quantum optimization algorithms offer a promising route to finding the ground states of target Hamiltonians on near-term quantum devices. None the less, it remains necessary to limit the evolution time and circuit depth as much as possible,…

Quantum Physics · Physics 2022-11-01 Chenfeng Cao , Yunlong Yu , Zipeng Wu , Nic Shannon , Bei Zeng , Robert Joynt

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

In this thesis, I investigate aspects of local Hamiltonians in quantum computing. First, I focus on the Adiabatic Quantum Computing model, based on evolution with a time dependent Hamiltonian. I show that to succeed using AQC, the…

Quantum Physics · Physics 2008-08-18 Daniel Nagaj

The variational quantum eigensolver (VQE) is an algorithm for finding the ground states of a given Hamiltonian. Its application to binary-formulated combinatorial optimization (CO) has been widely studied in recent years. However, typical…

Quantum Physics · Physics 2025-08-08 Ningyi Xie , Xinwei Lee , Tiejin Chen , Yoshiyuki Saito , Nobuyoshi Asai , Dongsheng Cai

A probabilistic imaginary-time evolution (PITE) method was proposed as a nonvariational method to obtain a ground state on a quantum computer. In this formalism, the success probability of obtaining all imaginary-time evolution operators…

Quantum Physics · Physics 2022-12-29 Hirofumi Nishi , Taichi Kosugi , Yusuke Nishiya , Yu-ichiro Matsushita

We introduce a method to solve the MaxCut problem efficiently based on quantum imaginary time evolution (QITE). We employ a linear Ansatz for unitary updates and an initial state involving no entanglement, as well as an…

In this study, we employed a quantum computer to solve a low-energy effective Hamiltonian for spin defects in diamond (so-called NV centre) and wurtzite-type aluminium nitride, which are anticipated to be qubits. The probabilistic…

We present efficient quantum algorithms for simulating time-dependent Hamiltonian evolution of general input states using an oracular model of a quantum computer. Our algorithms use either constant or adaptively chosen time steps and are…

Quantum Physics · Physics 2011-11-03 Nathan Wiebe , Dominic W. Berry , Peter Hoyer , Barry C. Sanders

An adaptive variational quantum imaginary time evolution (AVQITE) approach is introduced that yields efficient representations of ground states for interacting Hamiltonians on near-term quantum computers. It is based on McLachlan's…

Imaginary-time evolution plays an important role in algorithms for computing ground-state and thermal equilibrium properties of quantum systems, but can be challenging to simulate on classical computers. Many quantum algorithms for…

Quantum Physics · Physics 2025-07-22 Annie Ray , Esha Swaroop , Ningping Cao , Michael Vasmer , Anirban Chowdhury