English
Related papers

Related papers: The quantum computational speed of a single Cooper…

200 papers

We propose a new scheme for measuring the quantum efficiency of photon counting detectors by using correlated pho-tons. The measurement technique is based on a 90 rotation of the polarization of one photon member of a correlated pair…

Over the last few decades, developments in the physical limits of computing and quantum computing have increasingly taught us that it can be helpful to think about physics itself in computational terms. For example, work over the last…

Quantum Physics · Physics 2007-05-23 Michael P. Frank

When the boundary condition of a quantum system changes, how fast will it affect the state of the system? Here we show that if the response takes place immediately, then it can allow superluminal signal transfer. Else if the response…

Quantum Physics · Physics 2009-11-15 Guang Ping He

We derive algebraic bounds on achievable rates for quantum state transfer and entanglement generation in general quantum systems. We apply these bounds to graph-based models of local quantum spin systems to obtain speed limits on these…

Quantum Physics · Physics 2017-04-19 Jeffrey M. Epstein , K. Birgitta Whaley

Any protocol to process quantum information has to conclude with a measurement, aimed at producing a specific set of probabilities of measurement outcomes. In this work, we investigate the time, energy and importantly the genuine quantum…

Quantum Physics · Physics 2026-04-28 Agung Budiyono , Sebastian Deffner

The question of how fast a quantum state can evolve is considered. Using the definition of squared speed based on the Euclidean distance given in [Phys. Rev. Research, {\bf 2}, 033127 (2019)], we present a systematic framework to obtain the…

Quantum Physics · Physics 2024-02-05 Ashraf Naderzadeh-ostad , Seyed Javad Akhtarshenas

Quantum algorithms that can speed up certain tasks, such as factorisation and unstructured search, have driven a decades-long development of quantum computers and quantum technologies. Yet, outside specialized applications, quantum…

Quantum Physics · Physics 2019-07-05 Carlos Perez-Delgado , Sai Vinjanampathy

On the basis of introspective analysis, we establish a crucial requirement for the physical computation basis of consciousness: it should allow processing a significant amount of information together at the same time. Classical computation…

Quantum Physics · Physics 2009-12-31 Giuseppe Castagnoli

Spontaneous emission and the inelastic scattering of photons are two natural processes usually associated with decoherence and the reduction in the capacity to process quantum information. Here we show that when suitably detected, these…

Quantum Physics · Physics 2012-04-27 Marcelo F. Santos , Marcelo Terra Cunha , Rafael Chaves , Andre R. R. Carvalho

A computer, in order to perform a given computation, requires a certain amount of space (memory) and a certain amount of time (runtime). This leaves certain computations beyond reach due to technological limits on processing speed and…

High Energy Physics - Theory · Physics 2026-04-02 Leron Borsten , Hyungrok Kim

We propose a quantum Fourier transform on photons in which a single atom-coupled cavity system mediates the photon-photon interactions. Our protocol utilizes time-delay feedback of photons and requires no active feedforward control. The…

Quantum Physics · Physics 2022-07-18 Yu Shi , Edo Waks

The state function of a quantum object is undetermined with respect to its phase. This indeterminacy does not matter if it is global, but what if the components of the state have unknown relative phases? Can useful computations be performed…

Quantum Physics · Physics 2007-05-23 Subhash Kak

We propose a scheme for the ultrafast control of the emitter-field coupling rate in cavity quantum electrodynamics. This is achieved by the control of the vacuum field seen by the emitter through a modulation of the optical modes in a…

Quantum Physics · Physics 2015-03-23 Robert Johne , Ron Schutjens , Sartoon Fattah poor , Chao-Yuan Jin , Andrea Fiore

In standard quantum computation, the initial state is pure and the answer is determined by making a measurement of some of the bits in the computational basis. What can be accomplished if the initial state is a highly mixed state and the…

Quantum Physics · Physics 2009-01-23 E. Knill , R. Laflamme

The oracle model of computation is believed to allow a rigorous proof of quantum over classical computational superiority. Since quantum and classical oracles are essentially different, a correspondence principle is commonly implicitly used…

Quantum Physics · Physics 2007-05-23 Antoni Wojcik Ravindra W. Chhajlany

The performance of a quantum information processor depends on the precise control of phases introduced into the system during quantum gate operations. As the number of operations increases with the complexity of a computation, the phases of…

Quantum Physics · Physics 2014-11-06 I. V. Inlek , G. Vittorini , D. Hucul , C. Crocker , C. Monroe

Utilizing the program of expectation values in coherent states and its recently developed algorithmic tools, this letter investigates the dynamical properties of cosmological coherent states for Loop Quantum Gravity. To this end, the…

General Relativity and Quantum Cosmology · Physics 2022-06-22 Klaus Liegener , Łukasz Rudnicki

We consider a gedanken experiment with a beam of atoms in their ground state that are accelerated through a single-mode microwave cavity. We show that taking into account of the ''counter-rotating'' terms in the interaction Hamiltonian…

Quantum state preparation is vital to quantum computation and quantum information processing tasks. In adiabatic state preparation, the target state is theoretically obtained with nearly perfect fidelity if the control parameter is tuned…

Quantum Gases · Physics 2024-02-12 Xikun Li , Daniel Pęcak , Tomasz Sowiński , Jacob Sherson , Anne E. B. Nielsen

This paper discusses work developed in recent years, in the domain of quantum optics, which has led to a better understanding of the classical limit of quantum mechanics. New techniques have been proposed, and experimentally demonstrated,…

Quantum Physics · Physics 2015-06-26 Luiz Davidovich