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Related papers: An Analytic Theory of Quantum Imaginary Time Evolu…

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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

Quantum machine learning (QML) has emerged as an innovative framework with the potential to uncover complex patterns by leveraging quantum systems ability to simulate and exploit high-dimensional latent spaces, particularly in learning…

Quantum Physics · Physics 2025-04-08 Ziqing Guo , Alex Khan , Victor S. Sheng , Shabnam Jabeen , Ziwen Pan

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…

We consider the Quantum Natural Gradient Descent (QNGD) scheme which was recently proposed to train variational quantum algorithms. QNGD is Steepest Gradient Descent (SGD) operating on the complex projective space equipped with the…

Quantum Physics · Physics 2022-11-02 Touheed Anwar Atif , Uchenna Chukwu , Jesse Berwald , Raouf Dridi

With rapid advancements in machine learning, first-order algorithms have emerged as the backbone of modern optimization techniques, owing to their computational efficiency and low memory requirements. Recently, the connection between…

Quantum Physics · Physics 2025-05-21 Jiaqi Leng , Bin Shi

The variational quantum imaginary time evolution (VarQITE) algorithm is a near-term method to prepare the ground state and Gibbs state of Hamiltonians. Finding an appropriate parameterization of the quantum circuit is crucial to the success…

Quantum Physics · Physics 2023-07-26 Xiaoyang Wang , Yahui Chai , Maria Demidik , Xu Feng , Karl Jansen , Cenk Tüysüz

We propose a nonvariational scheme for geometry optimization of molecules for the first-quantized eigensolver, a recently proposed framework for quantum chemistry using the probabilistic imaginary-time evolution (PITE) on a quantum…

Quantum Physics · Physics 2023-11-06 Taichi Kosugi , Hirofumi Nishi , Yuichiro Matsushita

Solving combinatorial optimization problems using variational quantum algorithms (VQAs) has emerged as a promising research direction. Since the introduction of the Quantum Approximate Optimization Algorithm (QAOA), numerous variants have…

Quantum Physics · Physics 2025-07-28 Xin Wei Lee , Hoong Chuin Lau

In order to answer the problem of Quantum Phase Estimation Algorithm been not suitable for NISQ devices, and allows one to outperform classical computers, Variational Quantum Algorithms (VQAs) were designed. Our subject of interest is the…

Quantum Physics · Physics 2022-10-28 Max Alteg , Baptiste Chevalier , Octave Mestoudjian , Johan-Luca Rossi

Applying low-depth quantum neural networks (QNNs), variational quantum algorithms (VQAs) are both promising and challenging in the noisy intermediate-scale quantum (NISQ) era: Despite its remarkable progress, criticisms on the efficiency…

Quantum Physics · Physics 2023-07-11 Huan-Yu Liu , Zhao-Yun Chen , Tai-Ping Sun , Cheng Xue , Yu-Chun Wu , Guo-Ping Guo

Variational quantum algorithms (VQAs) are leading strategies for using near-term quantum devices, with a well-studied bottleneck being their trainability. Standard expectation-value objectives with expressive circuits frequently encounter…

Quantum Physics · Physics 2026-05-05 Yixian Qiu , Josep Lumbreras , Xiufan Li , Patrick Rebentrost

Variational quantum algorithms (VQAs) are prominent candidates for near-term quantum advantage but lack rigorous guarantees of convergence and generalization. By contrast, quantum phase estimation (QPE) provides provable performance under…

Quantum Physics · Physics 2025-10-09 Tuyen Nguyen , Mária Kieferová

We analyse quantile temporal-difference learning (QTD), a distributional reinforcement learning algorithm that has proven to be a key component in several successful large-scale applications of reinforcement learning. Despite these…

Hybrid quantum-classical adaptive Variational Quantum Eigensolvers (VQE) hold the potential to outperform classical computing for simulating many-body quantum systems. However, practical implementations on current quantum processing units…

Accurately solving high-dimensional partial differential equations (PDEs) remains a central challenge in computational mathematics. Traditional numerical methods, while effective in low-dimensional settings or on coarse grids, often…

Numerical Analysis · Mathematics 2025-05-26 Lucas Arenstein , Martin Mikkelsen , Michael Kastoryano

Non-Hermitian quantum systems exhibit unique properties and hold significant promise for diverse applications, yet their dynamical simulation poses a particular challenge due to intrinsic openness and non-unitary evolution. Here, we…

Quantum Physics · Physics 2025-10-21 Xiaogang Li , Kecheng Liu , Qiming Ding

Variational quantum algorithms (VQAs) represent a promising approach to utilizing current quantum computing infrastructures. VQAs are based on a parameterized quantum circuit optimized in a closed loop via a classical algorithm. This hybrid…

Quantum Physics · Physics 2024-04-10 David Fitzek , Robert S. Jonsson , Werner Dobrautz , Christian Schäfer

The success of the current generation of Noisy Intermediate-Scale Quantum (NISQ) hardware shows that quantum hardware may be able to tackle complex problems even without error correction. One outstanding issue is that of coherent errors…

We simulate the critical behavior of the Ising model utilizing a thermal state prepared using quantum computing techniques. The preparation of the thermal state is based on the variational quantum imaginary time evolution (QITE) algorithm.…

Quantum Physics · Physics 2023-09-07 Xiaoyang Wang , Xu Feng , Tobias Hartung , Karl Jansen , Paolo Stornati

In the emergent realm of quantum computing, the Variational Quantum Eigensolver (VQE) stands out as a promising algorithm for solving complex quantum problems, especially in the noisy intermediate-scale quantum (NISQ) era. However, the…

Quantum Physics · Physics 2024-03-13 Subhasree Bhattacharjee , Soumyadip Sarkar , Kunal Das , Bikramjit Sarkar