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Related papers: Certifying quantum memories with coherence

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Coherence of a quantum state intrinsically depends on the choice of the reference basis. A natural question to ask is the following: if we use two or more incompatible reference bases, can~there be some trade-off relation between the…

Quantum Physics · Physics 2016-07-20 Uttam Singh , Arun Kumar Pati , Manabendra Nath Bera

In the lectures we will be concerned with some aspects of physical implementations of quantum gate operations which are necessary for quantum information processing. We will discuss two possible realizations. One of them is based on qubits…

Quantum Physics · Physics 2007-05-23 Stefan Scheel , Jiannis Pachos , E. A. Hinds , Peter L. Knight

We describe how one may go about performing quantum computation with arbitrary "quantum stuff", as long as it has some basic physical properties. Imagine a long strip of stuff, equipped with regularly spaced wires to provide input settings…

Quantum Physics · Physics 2019-12-03 Lucien Hardy , Adam G. M. Lewis

Quantum measurements are not deterministic. For this reason quantum measurements are repeated for a number of shots on identically prepared systems. The uncertainty in each measurement depends on the number of shots and the expected outcome…

Quantum Physics · Physics 2025-03-12 Pieter Thijs Eendebak

I review recent works showing that information geometry is a useful framework to characterize quantum coherence and entanglement. Quantum systems exhibit peculiar properties which cannot be justified by classical physics, e.g. quantum…

Quantum Physics · Physics 2018-10-08 Davide Girolami

One of the main problems for the future of practical quantum computing is to stabilize the computation against unwanted interactions with the environment and imperfections in the applied operations. Existing proposals for quantum memories…

Quantum Physics · Physics 2007-05-23 Emanuel Knill , Raymond Laflamme

Quantum communication channels and quantum memories are the fundamental building blocks of large-scale quantum communication networks. Estimating their capacity to transmit and store quantum information is crucial in order to assess the…

Quantum Physics · Physics 2022-12-01 Ya-Dong Wu , Giulio Chiribella

The power of quantum computers relies on the capability of their components to maintain faithfully and process accurately quantum information. Since this property eludes classical certification methods, fundamentally new protocols are…

Quantum Physics · Physics 2018-11-07 Pavel Sekatski , Jean-Daniel Bancal , Sebastian Wagner , Nicolas Sangouard

Concomitant with the rapid development of quantum technologies, challenging demands arise concerning the certification and characterization of devices. The promises of the field can only be achieved if stringent levels of precision of…

Quantum Physics · Physics 2020-07-03 J. Eisert , D. Hangleiter , N. Walk , I. Roth , D. Markham , R. Parekh , U. Chabaud , E. Kashefi

The traditional formalism of quantum measurement (hereafter ``TQM'') describes processes where some properties of quantum states are extracted and stored as classical information. While TQM is a natural and appropriate description of how…

A new approach suitable for distributed quantum machine learning and exhibiting memory is proposed for a photonic platform. This measurement-based quantum reservoir computing takes advantage of continuous variable cluster states as the main…

Long-distance quantum communication via distant pairs of entangled quantum bits (qubits) is the first step towards more secure message transmission and distributed quantum computing. To date, the most promising proposals require quantum…

Quantum Physics · Physics 2009-11-13 O. A. Collins , S. D. Jenkins , A. Kuzmich , T. A. B. Kennedy

Quantum memory is a crucial component of a quantum information processor, just like a classical memory is a necessary ingredient of a conventional computer. Moreover, quantum memory of light would serve as a quantum repeater needed for…

Quantum Physics · Physics 2021-10-12 Kazuki Ikeda , Dmitri E. Kharzeev , Yuta Kikuchi

Various measures have been suggested recently for quantifying the coherence of a quantum state with respect to a given basis. We first use two of these, the l_1-norm and relative entropy measures, to investigate tradeoffs between the…

Quantum Physics · Physics 2015-10-08 Shuming Cheng , Michael J. W. Hall

If a quantum computer is stabilized by fault-tolerant quantum error correction (QEC), then most of its resources (qubits and operations) are dedicated to the extraction of error information. Analysis of this process leads to a set of…

Quantum Physics · Physics 2007-05-23 Andrew M. Steane

Just as classical information systems require buffers and memory, the same is true for quantum information systems. The potential that optical quantum information processing holds for revolutionising computation and communication is…

Quantum Physics · Physics 2017-08-23 M. Hosseini , G. Campbell , B. M. Sparkes , P. K. Lam , B. C. Buchler

Understanding temporal processes and their correlations in time is of paramount importance for the development of near-term technologies that operate under realistic conditions. Capturing the complete multi-time statistics defining a…

Quantum Physics · Physics 2020-04-28 Philip Taranto

Based on an idea that spatial separation of charge states can enhance quantum coherence, we propose a scheme for quantum computation with quantum bit (qubit) constructed from two coupled quantum dots. Quantum information is stored in…

Quantum Physics · Physics 2009-11-07 Xin-Qi Li , YiJing Yan

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

We introduce a rigorous framework for the quantification of coherence and identify intuitive and easily computable measures of coherence. We achieve this by adopting the viewpoint of coherence as a physical resource. By determining defining…

Quantum Physics · Physics 2014-10-07 T. Baumgratz , M. Cramer , M. B. Plenio