English
Related papers

Related papers: Staying adiabatic with unknown energy gap

200 papers

Quantum adiabatic evolution is a dynamical evolution of a quantum system under slow external driving. According to the quantum adiabatic theorem, no transitions occur between non-degenerate instantaneous eigen-energy levels in such a…

Quantum Physics · Physics 2015-06-18 Qi Zhang , Jiangbin Gong , Biao Wu

Recently, several approaches to solving linear systems on a quantum computer have been formulated in terms of the quantum adiabatic theorem for a continuously varying Hamiltonian. Such approaches enabled near-linear scaling in the condition…

Quantum Physics · Physics 2021-11-17 Pedro C. S. Costa , Dong An , Yuval R. Sanders , Yuan Su , Ryan Babbush , Dominic W. Berry

The preparation of a given quantum state on a quantum computing register is a typically demanding operation, requiring a number of elementary gates that scales exponentially with the size of the problem. Using the adiabatic theorem for…

Quantum Physics · Physics 2025-01-14 Davide Cugini , Davide Nigro , Mattia Bruno , Dario Gerace

We propose a general, fully gate-based quantum algorithm for counterdiabatic driving. The algorithm does not depend on heuristics as in previous variational methods, and exploits regularisation of the adiabatic gauge potential to suppress…

Quantum Physics · Physics 2024-10-10 Dyon van Vreumingen

The quantum speed limit specifies a universal bound of the fidelity between the initial state and the time-evolved state. We apply this method to find a bound of the fidelity between the adiabatic state and the time-evolved state. The bound…

Quantum Physics · Physics 2020-07-22 Keisuke Suzuki , Kazutaka Takahashi

We prove an analytical expression for the size of the gap between the ground and the first excited state of quantum adiabatic algorithm for the 3-satisfiability, where the initial Hamiltonian is a projector on the subspace complementary to…

Quantum Physics · Physics 2009-11-11 Marko Znidaric , Martin Horvat

A general time-dependent quantum system can be driven fast from its initial ground state to its final ground state without generating transitions by adding a steering term to the Hamiltonian. We show how this technique can be modified to…

Quantum Physics · Physics 2018-12-11 A. Barış Özgüler , Robert Joynt , Maxim G. Vavilov

We investigate Landau-Zener processes modeled by a two-level quantum system, with its finite bias energy varied in time and in the presence of a single broadened cavity mode at zero temperature. By applying the hierarchy equation method to…

Quantum Physics · Physics 2016-02-03 Zhe Sun , Longwen Zhou , Gaoyang Xiao , Dario Poletti , Jiangbin Gong

Transitions out of the ground space limit the performance of quantum adiabatic algorithms, while hardware imperfections impose stringent limitations on the circuit depth. We propose an adiabatic echo verification protocol which mitigates…

Quantum Physics · Physics 2024-09-06 Benjamin F. Schiffer , Dyon van Vreumingen , Jordi Tura , Stefano Polla

Quantum computation by adiabatic evolution, as described in quant-ph/0001106, will solve satisfiability problems if the running time is long enough. In certain special cases (that are classically easy) we know that the quantum algorithm…

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

The quantum adiabatic unstructured search algorithm is one of only a handful of quantum adiabatic optimization algorithms to exhibit provable speedups over their classical counterparts. With no fault tolerance theorems to guarantee the…

Quantum Physics · Physics 2019-11-14 Mikhail Slutskii , Tameem Albash , Lev Barash , Itay Hen

We show that by a suitable choice of a time dependent Hamiltonian, Deutsch's algorithm can be implemented by an adiabatic quantum computer. We extend our analysis to the Deutsch-Jozsa problem and estimate the required running time for both…

Quantum Physics · Physics 2009-11-07 Saurya Das , Randy Kobes , Gabor Kunstatter

Adiabatic gauge potential is the origin of nonadiabatic transitions. In counterdiabatic driving, which is a method of shortcuts to adiabaticity, adiabatic gauge potential can be used to realize identical dynamics to adiabatic time evolution…

Quantum Physics · Physics 2021-01-27 Takuya Hatomura , Kazutaka Takahashi

Grover's algorithm is one of the most important quantum algorithms, which performs the task of searching an unsorted database without a priori probability. Recently the adiabatic evolution has been used to design and reproduce quantum…

Quantum Physics · Physics 2007-05-23 Zhaohui Wei , Mingsheng Ying

We study the Landau-Zener Problem for a decaying two-level-system described by a non-hermitean Hamiltonian, depending analytically on time. Use of a super-adiabatic basis allows to calculate the non-adiabatic transition probability P in the…

Quantum Physics · Physics 2009-11-13 R. Schilling , Mark Vogelsberger , D. A. Garanin

We introduce and study the adiabatic dynamics of free-fermion models subject to a local Lindblad bath and in the presence of a time-dependent Hamiltonian. The merit of these models is that they can be solved exactly, and will help us to…

Quantum Physics · Physics 2017-11-20 Maximilian Keck , Simone Montangero , Giuseppe E. Santoro , Rosario Fazio , Davide Rossini

Digitizing an adiabatic evolution is a strategy able to combine the good performance of gate-based quantum processors with the advantages of adiabatic algorithms, providing then a hybrid model for efficient quantum information processing.…

Quantum Physics · Physics 2025-02-27 Alan C. Santos

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

We present a general method for studying coupled qubits driven by adiabatically changing external parameters. Extended calculations are provided for a two-bit Hamiltonian whose eigenstates can be used as logical states for a quantum CNOT…

Condensed Matter · Physics 2009-11-10 V. Corato , P. Silvestrini , L. Stodolsky , J. Wosiek

We study the Hamiltonian associated with the quantum adiabatic algorithm with a random cost function. Because the cost function lacks structure we can prove results about the ground state. We find the ground state energy as the number of…

Quantum Physics · Physics 2012-03-30 Edward Farhi , Jeffrey Goldstone , David Gosset , Sam Gutmann , Peter Shor