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Related papers: Nested composite NOT gates for quantum computation

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The creation of composite quantum gates that implement quantum response functions $\hat{U}(\theta)$ dependent on some parameter of interest $\theta$ is often more of an art than a science. Through inspired design, a sequence of $L$…

Quantum Physics · Physics 2018-02-02 Guang Hao Low , Theodore J. Yoder , Isaac L. Chuang

We design variational pulse sequences tailored for neutral atom quantum simulators and show that we can engineer layers of single-qubit and multi-qubit gates. As an application, we discuss how the proposed method can be used to perform…

Coherent operations constitutive for the implementation of single and multi-qubit quantum gates with trapped ions are demonstrated that are robust against variations in experimental parameters and intrinsically indeterministic system…

Quantum Physics · Physics 2011-12-23 N. Timoney , V. Elman , W. Neuhauser , Chr. Wunderlich

We propose a method for applying the quantum error-correction method for errors that occur during quantum gates. Using a perturbation treatment of the noise that allows us to separate it from the ideal evolution of the quantum gate, we…

Quantum Physics · Physics 2016-04-13 Leonardo Andreta de Castro , Reginaldo de Jesus Napolitano

We examine three possible implementations of non-deterministic linear optical cnot gates with a view to an in-principle demonstration in the near future. To this end we consider demonstrating the gates using currently available sources such…

Quantum Physics · Physics 2009-11-10 A. Gilchrist , W. J. Munro , A. G. White

We introduce a simple, widely applicable formalism for designing "error-divisible" two qubit gates: a quantum gate set where fractional rotations have proportionally reduced error compared to the full entangling gate. In current noisy…

Quantum Physics · Physics 2021-10-25 David Rodriguez Perez , Paul Varosy , Ziqian Li , Tanay Roy , Eliot Kapit , David Schuster

Ground states of spin lattices can serve as a resource for measurement-based quantum computation. Ideally, the ability to perform quantum gates via measurements on such states would be insensitive to small variations in the Hamiltonian.…

Quantum Physics · Physics 2012-06-20 Dominic V. Else , Ilai Schwarz , Stephen D. Bartlett , Andrew C. Doherty

Quantum error correction and fault-tolerance make it possible to perform quantum computations in the presence of imprecision and imperfections of realistic devices. An important question is to find the noise rate at which errors can be…

Quantum Physics · Physics 2016-06-30 Christopher Chamberland , Tomas Jochym-O'Connor , Raymond Laflamme

The implementation of fault-tolerant quantum gates on encoded logic qubits is considered. It is shown that transversal implementation of logic gates based on simple geometric control ideas is problematic for realistic physical systems…

Quantum Physics · Physics 2009-10-30 R. Nigmatullin , S. G. Schirmer

We propose a universal approach based on Hamiltonian inverse engineering to realize a set of parameterized two-qubit gates. This method possesses unique advantages to simultaneous control of transitions among four energy levels, providing a…

Quantum Physics · Physics 2026-03-06 Yang-Yang Yu , Guang-Hui Zhang , Yan-Jie He , Jun Wu , Xue-Ke Song , Dong Wang

The error-robust and short composite operations named ConCatenated Composite Pulses (CCCPs), developed as high-precision unitary operations in quantum information processing (QIP), are derived from composite pulses widely employed in…

There is a recent surge of interest and insights regarding the interplay of quantum optimal control and variational quantum algorithms. We study the framework in the context of qudits which are, for instance, definable as controllable…

Quantum Physics · Physics 2022-10-26 A. Barış Özgüler , Davide Venturelli

Near-term applications of quantum information processors will rely on optimized circuit implementations to minimize gate depth and therefore mitigate the impact of gate errors in noisy intermediate-scale quantum (NISQ) computers. More…

Quantum Physics · Physics 2020-12-21 Deanna M. Abrams , Nicolas Didier , Blake R. Johnson , Marcus P. da Silva , Colm A. Ryan

The principal obstacle to quantum information processing with many qubits is decoherence. One source of decoherence is spontaneous emission which causes loss of energy and information. Inability to control system parameters with high…

Quantum Physics · Physics 2009-11-10 Almut Beige , Hugo Cable , Peter L. Knight

Certain quantum codes allow logic operations to be performed on the encoded data, such that a multitude of errors introduced by faulty gates can be corrected. An important class of such operations are {\em transversal}, acting bitwise…

Quantum Physics · Physics 2007-09-11 Bei Zeng , Andrew Cross , Isaac L. Chuang

The conventional circuit paradigm, utilizing a limited number of gates to construct arbitrary quantum circuits, is hindered by significant noise overhead. For instance, the standard gate paradigm employs two CNOT gates for the partial…

Quantum Physics · Physics 2024-04-04 Jader P. Santos , Ben Bar , Raam Uzdin

Current experiments are taking the first steps toward noise-resilient logical qubits. Crucially, a quantum computer must not merely store information, but also process it. A fault-tolerant computational procedure ensures that errors do not…

Quantum Physics · Physics 2018-11-13 Earl T. Campbell , Barbara M. Terhal , Christophe Vuillot

We proposed a scheme to realize a controlled-NOT quantum logic gate in a dimer of exchange coupled single-molecule magnets, $[\textrm{Mn}_4]_2$. We chosen the ground state and the three low-lying excited states of a dimer in a finite…

Quantum Physics · Physics 2015-06-26 Jing-Min Hou , Li-Jun Tian , Mo-lin Ge

Quantum process tomography is a necessary tool for verifying quantum gates and diagnosing faults in architectures and gate design. We show that the standard approach of process tomography is grossly inaccurate in the case where the states…

We present a scalable uniform technique for construction of highly conditional C$^n$-NOT quantum gates of trapped ion qubits, such as the Toffoli gate, without using ancilla states and circuits of an exorbitant number of concatenated one-…

Quantum Physics · Physics 2015-05-28 Svetoslav S. Ivanov , Nikolay V. Vitanov