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Related papers: De-Signing Hamiltonians for Quantum Adiabatic Opti…

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Most research regarding quantum adiabatic optimization has focused on stoquastic Hamiltonians, whose ground states can be expressed with only real, nonnegative amplitudes. This raises the question of whether classical Monte Carlo algorithms…

Quantum Physics · Physics 2018-02-21 Jacob Bringewatt , William Dorland , Stephen P. Jordan , Alan Mink

In this review we consider the performance of the quantum adiabatic algorithm for the solution of decision problems. We divide the possible failure mechanisms into two sets: small gaps due to quantum phase transitions and small gaps due to…

Quantum Physics · Physics 2015-04-21 C. R. Laumann , R. Moessner , A. Scardicchio , S. L. Sondhi

Nonadiabatic holonomic quantum computation uses non-Abelian geometric phases to implement a universal set of quantum gates that are robust against control imperfections and decoherence. Until now, a number of three-level-based schemes of…

Quantum Physics · Physics 2018-11-16 G. F. Xu , D. M. Tong , Erik Sjöqvist

Many physically interesting models show a quantum phase transition when a single parameter is varied through a critical point, where the ground state and the first excited state become degenerate. When this parameter appears as a coupling…

Quantum Physics · Physics 2008-09-24 Gernot Schaller

In the circuit model of quantum computing, amplitude amplification techniques can be used to find solutions to NP-hard problems defined on $n$-bits in time $\text{poly}(n) 2^{n/2}$. In this work, we investigate whether such general…

In a quantum system with a smoothly and slowly varying Hamiltonian, which approaches a constant operator at times $t\to \pm \infty$, the transition probabilities between adiabatic states are exponentially small. They are characterized by an…

Quantum Physics · Physics 2009-10-31 Michael Wilkinson , Michael A. Morgan

Adiabatic quantum gate implementation generally takes longer time, which is disadvantageous in view of decoherence. In this report we implement several essential one-qubit quantum gates nonadiabatically by making use of a dynamical…

Quantum Physics · Physics 2014-04-10 Takumi Nitanda , Utkan Güngördü , Mikio Nakahara

Adiabatic processes driven by non-Hermitian, time-dependent Hamiltonians may be sped up by generalizing inverse engineering techniques based on Berry's transitionless driving algorithm or on dynamical invariants. We work out the basic…

Quantum Physics · Physics 2015-09-18 S. Ibáñez , S. Martínez-Garaot , Xi Chen , E. Torrontegui , J. G. Muga

Adiabatic quantum optimization is a procedure to solve a vast class of optimization problems by slowly changing the Hamiltonian of a quantum system. The evolution time necessary for the algorithm to be successful scales inversely with the…

Quantum Physics · Physics 2015-12-16 Salvatore Mandrà , Gian Giacomo Guerreschi , Alán Aspuru-Guzik

Perturbed Hamming weight problems serve as examples of optimization instances for which the adiabatic algorithm provably out performs classical simulated annealing. In this work we study the efficiency of the adiabatic algorithm for solving…

Quantum Physics · Physics 2015-11-24 Linghang Kong , Elizabeth Crosson

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

We propose a non-Hermitian generalization of stimulated Raman adiabatic passage (STIRAP), which allows one to increase speed and fidelity of the adiabatic passage. This is done by adding balanced imaginary (gain/loss) terms in the diagonal…

Quantum Physics · Physics 2015-06-19 Boyan T. Torosov , Giuseppe Della Valle , Stefano Longhi

Non-stoquastic Hamiltonians have both positive and negative signs in off-diagonal elements in their matrix representation in the standard computational basis and thus cannot be simulated efficiently by the standard quantum Monte Carlo…

Quantum Physics · Physics 2017-02-21 Hidetoshi Nishimori , Kabuki Takada

Consider a path of non-degenerate eigenstates of unitary operators or Hamiltonians with minimum eigenvalue gap G. The eigenpath traversal problem is to transform one or more copies of the initial to the final eigenstate. Solutions to this…

Quantum Physics · Physics 2015-03-17 S. Boixo , E. Knill , R. D. Somma

Designing proper time-dependent control fields for slowly varying the system to the ground state that encodes the problem solution is crucial for adiabatic quantum computation. However, inevitable perturbations in real applications demand…

Quantum Physics · Physics 2020-07-22 Xiaodong Yang , Ran Liu , Jun Li , Xinhua Peng

We derive a version of the adiabatic theorem that is especially suited for applications in adiabatic quantum computation, where it is reasonable to assume that the adiabatic interpolation between the initial and final Hamiltonians is…

Quantum Physics · Physics 2009-10-21 D. A. Lidar , A. T. Rezakhani , A. Hamma

Adiabatic quantum computation, based on the adiabatic theorem, is a promising alternative to conventional quantum computation. The validity of an adiabatic algorithm depends on the existence of a nonzero energy gap between the ground and…

Quantum Physics · Physics 2014-10-20 Da-Jian Zhang , Xiao-Dong Yu , D. M. Tong

It is believed that the presence of anticrossings with exponentially small gaps between the lowest two energy levels of the system Hamiltonian, can render adiabatic quantum optimization inefficient. Here, we present a simple adiabatic…

Quantum Physics · Physics 2013-05-30 Neil G. Dickson , Mohammad H. Amin

Adiabatic quantum computation employs a slow change of a time-dependent control function (or functions) to interpolate between an initial and final Hamiltonian, which helps to keep the system in the instantaneous ground state. When the…

Quantum Physics · Physics 2014-06-26 Constantin Brif , Matthew D. Grace , Mohan Sarovar , Kevin C. Young

At present, several models for quantum computation have been proposed. Adiabatic quantum computation scheme particularly offers this possibility and is based on a slow enough time evolution of the system, where no transitions take place. In…

Quantum Physics · Physics 2012-10-12 P. J. Salas Peralta