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

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The accurate implementation of quantum gates is essential for the realisation of quantum algorithms and digital quantum simulations. This accuracy may be increased on noisy hardware through the variational optimisation of gates, however the…

Quantum Physics · Physics 2021-07-14 Sean Greenaway , Frédéric Sauvage , Kiran E. Khosla , Florian Mintert

The implementation of quantum gates with fidelities that exceed the threshold for reliable quantum computing requires robust gates whose performance is not limited by the precision of the available control fields. The performance of these…

Quantum Physics · Physics 2015-12-30 Alexandre M. Souza , Roberto S. Sarthour , Ivan S. Oliveira , Dieter Suter

It is shown that a good estimate of the fidelity of an experimentally realized quantum process can be obtained by measuring the outputs for only two complementary sets of input states. The number of measurements required to test a quantum…

Quantum Physics · Physics 2009-11-10 Holger F. Hofmann

We characterize the quantum gate fidelity in a state-independent manner by giving an explicit expression for its variance. The method we provide can be extended to calculate all higher order moments of the gate fidelity. Using these results…

Quantum Physics · Physics 2012-04-30 Easwar Magesan , Robin Blume-Kohout , Joseph Emerson

Quantum logic gates can perform calculations much more efficiently than their classical counterparts. However, the level of control needed to obtain a reliable quantum operation is correspondingly higher. In order to evaluate the…

Quantum Physics · Physics 2009-11-13 Holger F. Hofmann , Ryo Okamoto , Shigeki Takeuchi

The information obtained from the operation of a quantum gate on only two complementary sets of input states is sufficient to estimate the quantum process fidelity of the gate. In the case of entangling gates, these conditions can be used…

Quantum Physics · Physics 2017-08-23 Holger F. Hofmann , Ryo Okamoto , Shigeki Takeuchi

Realistic quantum gates operate at non-vanishing noise levels. Therefore, it is necessary to evaluate the performance of each device according to some experimentally observable criteria of device performance. In this presentation, the…

Quantum Physics · Physics 2007-05-23 Holger F. Hofmann

Applications of quantum technology often require fidelities to quantify performance. These provide a fundamental yardstick for the comparison of two quantum states. While this is straightforward in the case of pure states, it is much more…

We consider procedures to realize an approximate universal NOT gate in terms of average fidelity and fidelity deviation. The average fidelity indicates the optimality of operation on average, while the fidelity deviation does the…

Quantum Physics · Physics 2012-12-24 Jeongho Bang , Seung-Woo Lee , Hyunseok Jeong , Jinhyoung Lee

When applied to different input states, an imperfect quantum operation yields output states with varying fidelities, defined as the absolute square of their overlap with the desired states. We present an expression for the distribution of…

Quantum Physics · Physics 2009-02-26 Line Hjortshoj Pedersen , Niels Martin Moller , Klaus Molmer

Gate fidelity -- an average fidelity over all possible input states -- is the workhorse metric for benchmarking quantum gates or circuits, yet fault-tolerant quantum computing ultimately depends on the worst-case behavior, typically…

Quantum Physics · Physics 2026-03-10 Kyoungho Cho , Ilkwon Sohn , Yongsoo Hwang , Jeongho Bang

There is currently a significant need for robust and efficient methods for characterizing quantum devices. While there has been significant progress in this direction, there remains a crucial need to precisely determine the strength and…

Quantum Physics · Physics 2019-09-04 Arnaud Carignan-Dugas , Joel J. Wallman , Joseph Emerson

We present Monte Carlo wavefunction simulations for quantum computations employing an exchange-coupled array of quantum dots. Employing a combination of experimentally and theoretically available parameters, we find that gate fidelities…

Quantum Physics · Physics 2007-05-23 E. Simon Myrgren , K. Birgitta Whaley

Quantum state transfer protocols are a major toolkit in many quantum information processing tasks, from quantum key distribution to quantum computation. To assess performance of a such a protocol, one often relies on the average fidelity…

We compare and contrast the error probability and fidelity as measures of the quality of the receiver's measurement strategy for a quantum communications system. The error probability is a measure of the ability to retrieve {\it classical}…

Quantum Physics · Physics 2009-11-07 Stephen M. Barnett , Claire R. Gilson , Masahide Sasaki

The paper analyzes the behavior of quantum channels, particularly in large dimensions, by proving various properties of the quantum gate fidelity. Many of these properties are of independent interest in the theory of distance measures on…

Quantum Physics · Physics 2011-07-12 Easwar Magesan

We generalize the experimental success criterion for quantum teleportation/memory in continuous-variable quantum systems to be suitable for non-unit-gain condition by considering attenuation/amplification of the coherent-state amplitude.…

Quantum Physics · Physics 2008-09-29 Ryo Namiki , Masato Koashi , Nobuyuki Imoto

Quantum computers will require encoding of quantum information to protect them from noise. Fault-tolerant quantum computing architectures illustrate how this might be done but have not yet shown a conclusive practical advantage. Here we…

Quantum Physics · Physics 2019-03-01 Robin Harper , Steven T. Flammia

We study how entanglement among the register qubits affects the gate fidelity in the one-way quantum computation if a measurement is inaccurate. We derive an inequality which shows that the mean gate fidelity is upper bounded by a…

Quantum Physics · Physics 2015-05-18 Tomoyuki Morimae

In theory, quantum computers can efficiently simulate quantum physics, factor large numbers and estimate integrals, thus solving otherwise intractable computational problems. In practice, quantum computers must operate with noisy devices…

Quantum Physics · Physics 2009-11-10 E. Knill
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