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Related papers: Gate Fidelities, Quantum Broadcasting, and Assessi…

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Measurement-based quantum computing is an alternative paradigm to the circuit-based model. This approach can be advantageous in certain scenarios, such as when read-out is fast and accurate, but two-qubit gates realized via inter-particle…

Quantum Physics · Physics 2021-11-16 Zhangjie Qin , Woo-Ram Lee , Brian DeMarco , Bryce Gadway , Svetlana Kotochigova , V. W. Scarola

Motivated by the gate set tomography we study quantum channels from the perspective of information which is invariant with respect to the gauge realized through similarity of matrices representing channel superoperators. We thus use the…

Quantum Physics · Physics 2018-04-13 Łukasz Rudnicki , Zbigniew Puchała , Karol Zyczkowski

As we approach the era of quantum advantage, when quantum computers (QCs) can outperform any classical computer on particular tasks, there remains the difficult challenge of how to validate their performance. While algorithmic success can…

In this work we aim at quantifying quantum channel output similarity. In order to achieve this, we introduce the notion of quantum channel superfidelity, which gives us an upper bound on the quantum channel fidelity. This quantity is…

Quantum Physics · Physics 2018-10-12 Łukasz Pawela , Zbigniew Puchała

An experimental success criterion for continuous-variable quantum teleportation and memories is to surpass a limit of the average fidelity achieved by the classical measure-and-prepare schemes with respect to a Gaussian distributed set of…

Quantum Physics · Physics 2011-04-25 Ryo Namiki

Measurement-based quantum computation is an efficient model to perform universal computation. Nevertheless, theoretical questions have been raised, mainly with respect to realistic noise conditions. In order to shed some light on this…

Quantum Physics · Physics 2012-10-22 L. G. E. Arruda , F. F. Fanchini , R. d. J. Napolitano , J. E. M. Hornos , A. O. Caldeira

We point out the similarities in the definition of the `fidelity' of a quantum system and the generating function determining the full counting statistics of charge transport through a quantum wire and suggest to use flux- or charge qubits…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 G. B. Lesovik , F. Hassler , G. Blatter

Successfully implementing a quantum algorithm involves maintaining a low logical error rate by ensuring the validity of the quantum fault-tolerance theorem. The required number of physical qubits arranged in an array depends on the chosen…

Quantum Physics · Physics 2024-10-01 Marco De Michielis , Elena Ferraro

Since the first demonstration of coherent control of a quantum state of a superconducting charge qubit a variety of Josephson-junction-based qubits have been implemented with remarkable progress in coherence time and read-out schemes.…

Mesoscale and Nanoscale Physics · Physics 2009-11-10 T. Yamamoto , Yu. A. Pashkin , O. Astafiev , Y. Nakamura , J. S. Tsai

Practical Quantum computing hinges on the ability to control large numbers of qubits with high fidelity. Quantum dots define a promising platform due to their compatibility with semiconductor manufacturing. Moreover, high-fidelity…

Mesoscale and Nanoscale Physics · Physics 2023-07-28 W. I. L. Lawrie , M. Rimbach-Russ , F. van Riggelen , N. W. Hendrickx , S. L. de Snoo , A. Sammak , G. Scappucci , J. Helsen , M. Veldhorst

We analyze the multifractality of the fidelity in an engineered Toffoli gate. Using quantum control methods, we define several optimization problems whose global solutions realize the gate in a chain of three qubits with XY Heisenberg…

Quantum Physics · Physics 2022-03-03 Jalil Khatibi Moqadam , Guilherme S. Welter , Paulo A. A. Esquef

Several information measures have recently been defined which capture the notion of "recoverability." In particular, the fidelity of recovery quantifies how well one can recover a system $A$ of a tripartite quantum state, defined on systems…

We have previously (quant-ph/9608012) shown that for quantum memories and quantum communication, a state can be transmitted over arbitrary distances with error $\epsilon$ provided each gate has error at most $c\epsilon$. We discuss a…

Quantum Physics · Physics 2008-02-03 E. Knill , R. Laflamme , W. Zurek

Large-scale digital quantum simulations require thousands of fundamental entangling gates to construct the simulated dynamics. Despite success in a variety of small-scale simulations, quantum information processing platforms have hitherto…

We show how quantum dynamics can be captured in the state of a quantum system, in such a way that the system can be used to stochastically perform, at a later time, the stored transformation perfectly on some other quantum system. Thus…

Quantum Physics · Physics 2009-11-07 G. Vidal , L. Masanes , J. I. Cirac

As quantum devices become more complex and the requirements on these devices become more demanding, it is crucial to be able to verify the performance of such devices in a scalable and reliable fashion. A cornerstone task in this challenge…

When a system undergoes a quantum phase transition, the ground-state wave-function shows a change of nature, which can be monitored using the fidelity concept. We introduce two Quantum Monte Carlo schemes that allow the computation of…

Strongly Correlated Electrons · Physics 2009-10-21 David Schwandt , Fabien Alet , Sylvain Capponi

Contemporary quantum computers encode and process quantum information in binary qubits (d = 2). However, many architectures include higher energy levels that are left as unused computational resources. We demonstrate a superconducting…

An average gate fidelity is a standard performance metric to quantify deviation between an ideal unitary gate transformation and its realistic experimental implementation. The average is taken with respect to states uniformly distributed…

Quantum Physics · Physics 2020-11-13 Filip Wudarski , Jeffrey Marshall , Andre Petukhov , Eleanor Rieffel

In this work, we introduce a comprehensive statistical framework for assessing single-qubit quantum teleportation performance beyond the conventional average-fidelity benchmark. At first, we derive a closed-form expression for the full…

Quantum Physics · Physics 2025-10-16 D. G. Bussandri , G. M. Bosyk , P. Crespo Del Amo , K. Życzkowski