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Related papers: Nonunitary quantum circuit

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Universal quantum computation requires the implementation of arbitrary control operations on the quantum register. In most cases, this is achieved by external control fields acting selectively on each qubit to drive single-qubit operations.…

Quantum Physics · Physics 2015-06-19 Jingfu Zhang , Daniel Burgarth , Raymond Laflamme , Dieter Suter

An important result in the theory of quantum control is the "universality" of $2$-local unitary gates, i.e. the fact that any global unitary evolution of a system of $L$ qudits can be implemented by composition of $2$-local unitary gates.…

Quantum Physics · Physics 2026-02-10 Marco Lastres , Frank Pollmann , Sanjay Moudgalya

Quantum gates based on geometric phases possess intrinsic noise-resilience features and therefore attract much attention. However, the implementations of previous geometric quantum computation typically require a long pulse time of gates.…

Quantum Physics · Physics 2022-10-10 Zhuang Ma , Jianwen Xu , Tao Chen , Yu Zhang , Wen Zheng , Dong Lan , Zheng-Yuan Xue , Xinsheng Tan , Yang Yu

We describe a method for achieving arbitrary 1-qubit gates and controlled-NOT gates within the context of the Single Cooper Pair Box (SCB) approach to quantum computing. Such gates are sufficient to support universal quantum computation.…

Quantum Physics · Physics 2007-05-23 P. Echternach , C. P. Williams , S. C. Dultz , P. Delsing , S. L. Braunstein , J. P. Dowling

Quantum circuit depth minimization is critical for practical applications of circuit-based quantum computation. In this work, we present a systematic procedure to decompose multiqubit controlled unitary gates, which is essential in many…

Quantum Physics · Physics 2022-10-06 Adenilton J. da Silva , Daniel K. Park

In this paper, we propose quantum circuits for runtime assertions, which can be used for both software debugging and error detection. Runtime assertion is challenging in quantum computing for two key reasons. First, a quantum bit (qubit)…

Quantum Physics · Physics 2019-10-23 Huiyang Zhou , Gregory Byrd

What resources are universal for quantum computation? In the standard model, a quantum computer consists of a sequence of unitary gates acting coherently on the qubits making up the computer. This paper shows that a very different model…

Quantum Physics · Physics 2009-11-07 Michael A. Nielsen

A novel universal and fault-tolerant basis (set of gates) for quantum computation is described. Such a set is necessary to perform quantum computation in a realistic noisy environment. The new basis consists of two single-qubit gates…

Quantum Physics · Physics 2007-05-23 P. Oscar Boykin , Tal Mor , Matthew Pulver , Vwani Roychowdhury , Farrokh Vatan

A large-scalable quantum computer model, whose qubits are represented by the subspace subtended by the ground state and the single exciton state on semiconductor quantum dots, is proposed. A universal set of quantum gates in this system may…

Quantum Physics · Physics 2009-11-10 Kaiyu Yang , Shi-Liang Zhu , Z. D. Wang

We present a concept of non-Gaussian measurement composed of a non-Gaussian ancillary state, linear optics and adaptive heterodyne measurement, and on the basis of this we also propose a simple scheme of implementing a quantum cubic gate on…

We define and construct efficient depth-universal and almost-size-universal quantum circuits. Such circuits can be viewed as general-purpose simulators for central classes of quantum circuits and can be used to capture the computational…

Computational Complexity · Computer Science 2008-04-16 Debajyoti Bera , Stephen Fenner , Frederic Green , Steve Homer

We propose a scalable scheme for optical quantum computing using measurement-induced continuous-variable quantum gates in a loop-based architecture. Here, time-bin-encoded quantum information in a single spatial mode is deterministically…

Quantum Physics · Physics 2017-09-27 Shuntaro Takeda , Akira Furusawa

In this paper is presented an abstract theory of quantum processors and controllers, special kind of quantum computational network defined on a composite quantum system with two parts: the controlling and controlled subsystems. Such…

Quantum Physics · Physics 2010-05-12 Alexander Yu. Vlasov

We propose a theory of characterizing quantum circuits with qubit functional configurations. Any quantum circuit can be decomposed into alternating sequences of 1-qubit unitary gates and CNOT gates. Each CNOT sequence prepares the current…

Quantum Physics · Physics 2022-05-13 Zixuan Hu , Sabre Kais

We propose a method of compiling that permits to identify quantum circuits able to simulate arbitrary $n$-qubit unitary operations via the adjustment of angles in single-qubit gates therein. The method of compiling itself extends older…

Quantum Physics · Physics 2021-01-06 Rahul P. Singh , A. Mandilara

Quantum measurement is universal for quantum computation. This universality allows alternative schemes to the traditional three-step organisation of quantum computation: initial state preparation, unitary transformation, measurement. In…

Quantum Physics · Physics 2007-05-23 Simon Perdrix , Philippe Jorrand

From a geometric approach, we derive the minimum number of applications needed for an arbitrary Controlled-Unitary gate to construct a universal quantum circuit. A new analytic construction procedure is presented and shown to be either…

Quantum Physics · Physics 2009-11-10 Jun Zhang , Jiri Vala , Shankar Sastry , K. Birgitta Whaley

We show that the integrable Lindblad superoperators found recently can be used to build integrable nonunitary quantum circuits with two-site gates by demonstrating that the $\check{R}$-matrices are completely positive and trace preserving.…

Strongly Correlated Electrons · Physics 2022-11-09 Lei Su , Ivar Martin

Quantum measurement is universal for quantum computation. This universality allows alternative schemes to the traditional three-step organisation of quantum computation: initial state preparation, unitary transformation, measurement. In…

Quantum Physics · Physics 2016-09-08 Simon Perdrix , Philippe Jorrand

The quantum circuit model is the most widely used model of quantum computation. It provides both a framework for formulating quantum algorithms and an architecture for the physical construction of quantum computers. However, several other…

Quantum Physics · Physics 2008-09-16 Stephen P. Jordan