English
Related papers

Related papers: An Alternative Approach to Quantum Imaginary Time …

200 papers

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

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

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

Simulating quantum imaginary-time evolution (QITE) is a major promise of quantum computation. However, the known algorithms are either probabilistic (repeat until success) with impractically small success probabilities or coherent (quantum…

Quantum Physics · Physics 2023-11-02 Thais de Lima Silva , Márcio M. Taddei , Stefano Carrazza , Leandro Aolita

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

A fast implementation of the quantum imaginary time evolution (QITE) algorithm called Fast QITE is proposed. The algorithmic cost of QITE typically scales exponentially with the number of particles it nontrivially acts on in each Trotter…

Quantum Physics · Physics 2020-09-28 Kok Chuan Tan

We calculate the energy levels and corresponding eigenstates of an interacting scalar quantum field theory on a lattice using a continuous-variable version of the quantum imaginary time evolution algorithm. Only a single qumode is needed…

Quantum Physics · Physics 2022-01-19 Kübra Yeter-Aydeniz , Eleftherios Moschandreou , George Siopsis

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…

Preparing ground states of strongly correlated quantum systems is a central goal in quantum simulation and optimization. The feedback-based quantum algorithm (FALQON) provides an attractive alternative to variational methods with a fully…

Quantum Physics · Physics 2025-12-16 Thanh Nguyen Van Long , Lan Nguyen Tran , Le Bin Ho

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

The current generation of noisy intermediate scale quantum computers introduces new opportunities to study quantum many-body systems. In this paper, we show that quantum circuits can provide a dramatically more efficient representation than…

Quantum Physics · Physics 2021-03-24 Sheng-Hsuan Lin , Rohit Dilip , Andrew G. Green , Adam Smith , Frank Pollmann

The quantum imaginary time evolution is a powerful algorithm for preparing the ground and thermal states on near-term quantum devices. However, algorithmic errors induced by Trotterization and local approximation severely hinder its…

Quantum Physics · Physics 2022-03-16 Chenfeng Cao , Zheng An , Shi-Yao Hou , D. L. Zhou , Bei Zeng

The quantum imaginary time evolution (QITE) algorithm is a direct implementation of the classical imaginary time evolution algorithm on quantum computer. We implement the QITE algorithm for the case of nuclear Hartree-Fock equations in a…

Nuclear Theory · Physics 2024-12-02 Yang Hong Li , Jim Al-Khalili , Paul Stevenson

We introduce an adiabatic state preparation protocol which implements quantum imaginary time evolution under the Hamiltonian of the system. Unlike the original quantum imaginary time evolution algorithm, adiabatic quantum imaginary time…

Quantum Physics · Physics 2024-04-23 Kasra Hejazi , Mario Motta , Garnet Kin-Lic Chan

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 computing employs controllable interactions to perform sequences of logical gates and entire algorithms on quantum registers. This paradigm has been widely explored, e.g., for simulating dynamics of manybody systems by decomposing…

Quantum Physics · Physics 2025-05-21 S. Alipour , A. T. Rezakhani , Alireza Tavanfar , K. Mölmer , T. Ala-Nissila

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

Optimization problems in finance, physics and computer science are typically very hard to tackle in classical computing and quantum computing could help speed up computations and provide efficient methods for tackling large problems.…

Quantum Physics · Physics 2025-11-26 Dawei Zhong , Akhil Francis , Ermal Rrapaj

We reveal the power of Grover's algorithm from thermodynamic and geometric perspectives by showing that it is a product formula approximation of imaginary-time evolution (ITE), a Riemannian gradient flow on the special unitary group. This…

Quantum Physics · Physics 2026-02-13 Yudai Suzuki , Marek Gluza , Jeongrak Son , Bi Hong Tiang , Nelly H. Y. Ng , Zoë Holmes