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We expand upon the standard quantum adiabatic theorem, examining the time-dependence of quantum evolution in the near-adiabatic limit. We examine a Hamiltonian that evolves along some fixed trajectory from $\hat{H}_0$ to $\hat{H}_1$ in a…

Quantum Physics · Physics 2018-05-07 Lucas Brady , Wim van Dam

A major challenge in quantum computing is to solve general problems with limited physical hardware. Here, we implement digitized adiabatic quantum computing, combining the generality of the adiabatic algorithm with the universality of the…

Over the last decades, there have been many proposals for quantum computation. One of the promising candidates is adiabatic quantum computation (AQC). The central idea of AQC is about finding the ground state of a system with a problem…

Quantum Physics · Physics 2017-04-12 P. V. Pyshkin , Da-Wei Luo , J. Q. You , Lian-Ao Wu

The adiabatic theorem in quantum mechanics implies that if a system is in a discrete eigenstate of a Hamiltonian and the Hamiltonian evolves in time arbitrarily slowly, the system will remain in the corresponding eigenstate of the evolved…

Quantum Physics · Physics 2025-04-02 Thomas D. Cohen , Hyunwoo Oh

Existing quantum algorithms for quantum chemistry work well near the equilibrium geometry of molecules, but the results can become unstable when the chemical bonds are broken at large atomic distances. For any adiabatic approach, this…

Chemical Physics · Physics 2023-05-09 Hongye Yu , Deyu Lu , Qin Wu , Tzu-Chieh Wei

We propose a protocol for quantum adiabatic optimization, whereby an intermediary Hamiltonian that is diagonal in the computational basis is turned on and off during the interpolation. This `diagonal catalyst' serves to bias the energy…

Quantum Physics · Physics 2021-02-16 Tameem Albash , Matthew Kowalsky

The quantum adiabatic algorithm is a Hamiltonian based quantum algorithm designed to find the minimum of a classical cost function whose domain has size N. We show that poor choices for the Hamiltonian can guarantee that the algorithm will…

Quantum Physics · Physics 2008-06-30 Edward Farhi , Jeffrey Goldstone , Sam Gutmann , Daniel Nagaj

The ability to efficiently prepare ground states of quantum Hamiltonians via adiabatic protocols is typically limited by the smallest energy gap encountered during the quantum evolution. This presents a key obstacle for quantum simulation…

We introduce an algorithm to perform an optimal adiabatic evolution that operates without an apriori knowledge of the system spectrum. By probing the system gap locally, the algorithm maximizes the evolution speed, thus minimizing the total…

Quantum Physics · Physics 2011-05-10 J. Nehrkorn , S. Montangero , A. Ekert , A. Smerzi , R. Fazio , T. Calarco

Variational quantum algorithms (VQAs) have emerged in recent years as a promise to obtain quantum advantage. These task-oriented algorithms work in a hybrid loop combining a quantum processor and classical optimization. Using a specific…

The viability of adiabatic quantum computation depends on the slow evolution of the Hamiltonian. The adiabatic switching theorem provides an asymptotic series for error estimates in $1/T$, based on the lowest non-zero derivative of the…

Quantum Physics · Physics 2025-12-25 Thomas D. Cohen , Andrew Li , Hyunwoo Oh , Maneesha Sushama Pradeep

The variational quantum eigensolver (or VQE) uses the variational principle to compute the ground state energy of a Hamiltonian, a problem that is central to quantum chemistry and condensed matter physics. Conventional computing methods are…

We propose a novel adiabatic time evolution (ATE) method for obtaining the ground state of a quantum many-electron system on a quantum circuit based on first quantization. As a striking feature of the ATE method, it consists of only unitary…

Quantum Physics · Physics 2024-03-18 Yusuke Nishiya , Hirofumi Nishi , Yannick Couzinié , Taichi Kosugi , Yu-ichiro Matsushita

Estimating molecular ground-state energies is a central application of quantum computing, requiring both the preparation of accurate quantum states and efficient energy readout. Understanding the effect of hardware noise on these…

Quantum Physics · Physics 2025-12-23 Ludwig Nützel , Michael J. Hartmann , Henrik Dreyer , Etienne Granet

Quantum adiabatic algorithms are commonly analyzed through local spectral properties of an interpolating Hamiltonian, most notably the minimum energy gap. While this perspective captures an important constraint on adiabatic runtimes, it…

Quantum Physics · Physics 2026-01-06 Prathamesh S. Joshi

Adiabatic quantum algorithms must evolve slowly enough to suppress non-adiabatic transitions while remaining fast enough to be practical. In open systems, this trade-off is reshaped by decoherence. For Hamiltonians subject to dephasing…

Quantum Physics · Physics 2026-03-31 Afaf El Kalai , Peter J. Eder , Christian B. Mendl

Variational quantum algorithms (VQAs) are hybrid quantum-classical approaches used for tackling a wide range of problems on noisy intermediate-scale quantum (NISQ) devices. Testing these algorithms on relevant hardware is crucial to…

Quantum adiabatic algorithm is a method of solving computational problems by evolving the ground state of a slowly varying Hamiltonian. The technique uses evolution of the ground state of a slowly varying Hamiltonian to reach the required…

Quantum Physics · Physics 2015-06-26 Avik Mitra , Arindam Ghosh , Ranabir Das , Apoorva Patel , Anil Kumar

The Quantum Approximate Optimization Algorithm (QAOA) exhibits significant potential for tackling combinatorial optimization problems. Despite its promise for near-term quantum devices, a major challenge in applying QAOA lies in the cost of…

Quantum Physics · Physics 2024-01-23 Mingyou Wu , Hanwu Chen

In recent years, variational quantum algorithms (VQAs) have gained significant attention due to their adaptability and efficiency on near-term quantum hardware. They have shown potential in a variety of tasks, including linear algebra,…

Quantum Physics · Physics 2024-12-06 Yigal Ilin , Itai Arad