English
Related papers

Related papers: Exchange Gate on the Qudit Space and Fock Space

200 papers

It is known that it is possible to encode a logical qubit over many physical qubits such that it is immune to the effects of collective decoherence, and it is possible to perform universal quantum computation using these `decoherence-free'…

Quantum Physics · Physics 2013-10-30 Bobby Antonio , Sougato Bose

Effective quantum information processing is tantamount in part to the minimization the quantum resources needed by quantum logic gates. Here, we propose an optimization of an n-controlled-qubit Fredkin gate with a maximum of 2n+1 two-qubit…

Quantum Physics · Physics 2020-12-01 Wen-Qiang Liu , Hai-Rui Wei , Leong-Chuan Kwek

A new approach to single-qubit operations using exchange interactions of single electrons in gate-defined quantum dots has recently been demonstrated: the resonant exchange qubit. We show that two-qubit operations, specifically the CPHASE…

Mesoscale and Nanoscale Physics · Physics 2013-08-09 Andrew C. Doherty , Matthew P. Wardrop

We introduce the paradigm of replacement-type quantum gates. This type of gate introduces input qubits, candidate qubits, and output qubits. The candidate qubits are prepared such, that a displacement conditional on the input qubit results…

Quantum Physics · Physics 2026-02-24 Florian Ginzel , Javad Kazemi , Valentin Torggler , Wolfgang Lechner

We theoretically propose a set of universal quantum gates acting on a hybrid qubit formed by coupling a quantum dot spin qubit and Majorana fermion qubit. First, we consider a quantum dot tunnel-coupled to two topological superconductors.…

Mesoscale and Nanoscale Physics · Physics 2016-08-03 Silas Hoffman , Constantin Schrade , Jelena Klinovaja , Daniel Loss

We theoretically study specific schemes for performing a fundamental two-qubit quantum gate via controlled atomic collisions by switching microscopic potentials. In particular we calculate the fidelity of a gate operation for a…

Quantum Physics · Physics 2009-10-31 T. Calarco , E. A. Hinds , D. Jaksch , J. Schmiedmayer , J. I. Cirac , P. Zoller

Although the quality of quantum bits (qubits) and quantum gates has been steadily improving, the available quantity of qubits has increased quite slowly. To address this important issue in quantum computing, we have demonstrated arbitrary…

Quantum Physics · Physics 2016-06-29 Yang Wang , Aishwarya Kumar , Tsung-Yao Wu , David S. Weiss

We construct a quantum gate entangler based on selective phase rotation transform. In particular, we established a relation between quantum integral transform and quantum gates entangler in terms of universal controlled gates for…

Quantum Physics · Physics 2009-12-21 Hoshang Heydari

The three-spin-$1/2$ decoherence-free subsystem defines a logical qubit protected from collective noise and supports exchange-only universal gates. Such logical qubits are well-suited for implementation with electrically-defined quantum…

Quantum Physics · Physics 2019-04-26 James. R. van Meter , Emanuel Knill

We propose an approach to realize quantum gates with electron spins localized in a semiconductor that uses double occupancy to advantage. With a fast (non-adiabatic) time control of the tunnelling, the probability of double occupancy is…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 T. A. Kaplan , C. Piermarocchi

The benefit of exchange-only qubits compared to other spin qubit types is the universal control using only voltage controlled exchange interactions between neighboring spins. As a compromise, qubit operations have to be constructed from…

The SWAP gate has become an integral feature of quantum circuit architectures and is designed to permute the states of two qubits through the use of the well-known controlled-NOT gate. We consider the question of whether a two-qudit quantum…

Quantum Physics · Physics 2015-03-17 Colin Wilmott

Each year, the gap between theoretical proposals and experimental endeavours to create quantum computers gets smaller, driven by the promise of fundamentally faster algorithms and quantum simulations. This occurs by the combination of…

Quantum Physics · Physics 2016-04-20 Bobby Antonio

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

Qudit, a high-dimensional quantum system, provides a larger Hilbert space to process the quantum information and has shown remarkable advantages over the qubit counterparts. It is a great challenge to realize the high fidelity universal…

Quantum Physics · Physics 2023-12-01 Zhe Meng , Wen-Qiang Liu , Bo-Wen Song , Xiao-Yun Wang , An-Ning Zhang , Zhang-Qi Yin

We study quantum information processing using superpositions of Fock states in superconducting resonators, as quantum $d$-level systems (qudits). A universal set of single and coupled logic gates is theoretically proposed for resonators…

Quantum Physics · Physics 2015-05-30 Frederick W. Strauch

Exchange-only quantum computation is a version of spin-based quantum computation that entirely avoids the difficulty of controlling individual spins by a magnetic field and instead functions by sequences of exchange pulses. The challenge…

Quantum Physics · Physics 2024-02-19 Violeta N. Ivanova-Rohling , Niklas Rohling , Guido Burkard

In this study, we construct the quantum reversible counterparts of the logical AND, OR, XOR, NOR, and NAND gates. We utilize a quantum Fourier transform (QFT)-based adder circuit that replicates the functionality of a digital half-adder,…

Quantum Physics · Physics 2025-04-25 Ayda Kaltehei , Murat Kurt , Azmi Gençten , Selçuk Çakmak

The Heisenberg exchange interaction is a natural method to implement non-local (i.e., multi-qubit) quantum gates in quantum information processing. We consider quantum circuits comprising of $(SWAP)^\alpha $ gates, which are realized…

Quantum Physics · Physics 2009-11-10 Heng Fan , Vwani Roychowdhury , Thomas Szkopek

We propose a scheme for quantum computing using high-Q cavities in which the qubits are represented by single cavity modes restricted in the space spanned by the two lowest Fock states. We show that single qubit operations and universal…

Quantum Physics · Physics 2009-11-06 V. Giovannetti , D. Vitali , P. Tombesi , A. Ekert