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Related papers: Hamiltonians for Quantum Computing

200 papers

Building a quantum computer is a daunting challenge since it requires good control but also good isolation from the environment to minimize decoherence. It is therefore important to realize quantum gates efficiently, using as few operations…

Quantum Physics · Physics 2019-10-28 T. Bækkegaard , L. B. Kristensen , N. J. S. Loft , C. K. Andersen , D. Petrosyan , N. T. Zinner

Quantum simulation uses a well-known quantum system to predict the behavior of another quantum system. Certain limitations in this technique arise, however, when applied to specific problems, as we demonstrate with a theoretical and…

Quantum Physics · Physics 2009-11-13 Kenneth R. Brown , Robert J. Clark , Isaac L. Chuang

An architecture for a quantum computer is presented in which spins associated with donors in silicon function as qubits. Quantum operations on the spins are performed using a combination of voltages applied to gates adjacent to the spins…

Quantum Physics · Physics 2015-06-26 B. E. Kane

We suggest an architecture for quantum computing with spin-pair encoded qubits in silicon. Electron-nuclear spin-pairs are controlled by a dc magnetic field and electrode-switched on and off hyperfine interaction. This digital processing is…

Quantum Physics · Physics 2009-11-07 A. J. Skinner , M. E. Davenport , B. E. Kane

Interesting problems in quantum computation take the form of finding low-energy states of (pseudo)spin systems with engineered Hamiltonians that encode the problem data. Motivated by the practical possibility of producing very…

Quantum Physics · Physics 2022-05-11 Jiajin Feng , Biao Wu , Frank Wilczek

If NMR systems are to be used as practical quantum computers, the number of coupled spins will need to be so large that it is not feasible to rely on purely heteronuclear spin systems. The implementation of a quantum logic gate imposes…

Quantum Physics · Physics 2009-10-31 Noah Linden , Eriks Kupce , Ray Freeman

Exploiting inherent symmetries is a common and effective approach to speed up the simulation of quantum systems. However, efficiently accounting for non-Abelian symmetries, such as the $SU(2)$ total-spin symmetry, remains a major challenge.…

Quantum Physics · Physics 2024-12-20 Anthony Gandon , Alberto Baiardi , Max Rossmannek , Werner Dobrautz , Ivano Tavernelli

Quantum computing using two-dimensional NMR has recently been described using scalar coupling evolution technique [J. Chem. Phys.,109,10603 (1998)]. In the present paper, we describe two-dimensional NMR quantum computing with the help of…

Quantum Physics · Physics 2007-05-23 T. S. Mahesh , Kavita Dorai , Arvind , Anil Kumar

We show that a wide range of spin clusters with antiferromagnetic intracluster exchange interaction allows one to define a qubit. For these spin cluster qubits, initialization, quantum gate operation, and readout are possible using the same…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 Florian Meier , Jeremy Levy , Daniel Loss

Digital-analog quantum computation aims to reduce the currently infeasible resource requirements needed for near-term quantum information processing by replacing sequences of one- and two-qubit gates with a unitary transformation generated…

The past few years have witnessed the concrete and fast spreading of quantum technologies for practical computation and simulation. In particular, quantum computing platforms based on either trapped ions or superconducting qubits have…

Quantum Physics · Physics 2020-04-21 Francesco Tacchino , Alessandro Chiesa , Stefano Carretta , Dario Gerace

We show how to implement quantum computation on a system with an intrinsic Hamiltonian by controlling a limited subset of spins. Our primary result is an efficient control sequence on a nearest-neighbor XY spin chain through control of a…

Quantum Physics · Physics 2010-01-27 Alastair Kay , Peter J. Pemberton-Ross

We present a general method which expresses a unitary operator by the product of operators allowed by the Hamiltonian of spin-1/2 systems. In this method, the generator of an operator is found first, and then the generator is expanded by…

Quantum Physics · Physics 2009-10-31 Jaehyun Kim , Jae-Seung Lee , Soonchil Lee

Given the Hamiltonian, the evaluation of unitary operators has been at the heart of many quantum algorithms. Motivated by existing deterministic and random methods, we present a hybrid approach, where Hamiltonians with large amplitude are…

Quantum Physics · Physics 2021-09-17 Shi Jin , Xiantao Li

Spins based in silicon provide one of the most promising architectures for quantum computing. A scalable design for silicon-germanium quantum dot qubits is presented. The design incorporates vertical and lateral tunneling. Simulations of a…

The application of quantum algorithms to the study of many-particle quantum systems requires the ability to prepare wavefunctions that are relevant in the behavior of the system under study. Hamiltonian symmetries are an important…

Quantum Physics · Physics 2022-03-22 Alessandro Carbone , Davide Emilio Galli , Mario Motta , Barbara Jones

Quantum computation offers the potential to solve fundamental yet otherwise intractable problems across a range of active fields of research. Recently, universal quantum-logic gate sets - the building blocks for a quantum computer - have…

This work proposes numerical tests which determine whether a two-qubit operator has an atypically simple quantum circuit. Specifically, we describe formulae, written in terms of matrix coefficients, characterizing operators implementable…

Quantum Physics · Physics 2009-11-10 Vivek V. Shende , Stephen S. Bullock , Igor L. Markov

We present a Hamiltonian quantum computation scheme universal for quantum computation (BQP). Our Hamiltonian is a sum of a polynomial number (in the number of gates L in the quantum circuit) of time-independent, constant-norm, 2-local…

Quantum Physics · Physics 2013-05-30 Daniel Nagaj

Today's devices for quantum computing are still far from implementing useful and powerful quantum algorithms. Decoherence and the wish to resist the effects of errors in a system of quantum bits incurs a lot of overhead in the number of…

Quantum Physics · Physics 2007-05-23 Torsten Asselmeyer-Maluga , Matthias Kolbe , Helge Rose'