Localized Excitation of Single Atom to a Rydberg State with Structured Laser Beam for Quantum Information

Control fields in quantum information processing are almost by definition assumed to be classical. In reality, however, when such a field is used to manipulate the quantum state of qubits, the qubits always become slightly entangled with the field. For quantum information processing this is an undesirable property, as it precludes perfect quantum computing and quantum communication. Here we consider the interaction of atomic qubits with laser fields and quantify atom-field entanglement in various cases of interest. We find that the entanglement decreases with the average number of photons \bar{n} in a laser beam as $E\propto\log_2 \bar{n}/\bar{n}$ for $\bar{n}\rightarrow\infty$.

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Quantum Information

MRS Bulletin ◽

10.1557/mrs2005.28 ◽

2005 ◽

Vol 30 (2) ◽

pp. 99-104 ◽

Cited By ~ 2

Author(s):

Luiz Davidovich

Keyword(s):

Quantum Information ◽

San Francisco ◽

Quantum Physics ◽

Quantum Algorithms ◽

Rapid Development ◽

Superposition Principle ◽

Deep Understanding ◽

Single Atom ◽

Recent Developments ◽

Fundamental Research

AbstractThe following article is based on the plenary address by Luiz Davidovich (Federal University of Rio de Janeiro), presented on April 14, 2004, at the 2004 MRS Spring Meeting in San Francisco. The field of quantum information is a discipline that aims to investigate methods for characterizing, transmitting, storing, compressing, and computationally utilizing the information carried by quantum states. It owes its rapid development over the last few years to several factors: the ability, developed in several laboratories, to control and measure simple microscopic systems; the discovery of fast quantum algorithms; and the recognition that Moore's law will soon lead to the single-atom limit of elementary computing gates.Cryptography and quantum computing are among the main applications in the field.They rely on the subtle and fundamental properties of the quantum world: the unavoidable disturbance associated with measurement, the superposition principle, and the nonlocal properties of entangled states. Progress in this area is intimately connected to a deep understanding of quantum physics: recent achievements include the experimental demonstration of teleportation and detailed investigations of the role of the environment in the quantum–classical transition. This article reviews basic concepts and recent developments in the field of quantum information, emphasizing the close ties between fundamental research and possible applications.

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Conditional operation using three degrees of freedom of a laser beam for application in quantum information

Journal of the Optical Society of America B ◽

10.1364/josab.33.001649 ◽

2016 ◽

Vol 33 (8) ◽

pp. 1649 ◽

Cited By ~ 6

Author(s):

W. F. Balthazar ◽

J. A. O. Huguenin

Keyword(s):

Quantum Information ◽

Laser Beam ◽

Degrees Of Freedom ◽

Three Degrees Of Freedom

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Quantum Computation and Quantum Information by Michael E. Nielson and Isaac L. Chuang

Mapana Journal of Sciences ◽

10.12723/mjs.2.10 ◽

2003 ◽

Vol 1 (2) ◽

pp. 120-121

Author(s):

Neeraj Sinha

Keyword(s):

Quantum Mechanics ◽

Quantum Information ◽

Quantum Computation ◽

Semiconductor Industry ◽

Atomic Level ◽

Present Form ◽

Single Atom ◽

Large Size ◽

Physical Laws ◽

Ultimate Limit

One of the most promising scieniifc of East century was the Computers. Computers of initial days were of very large size consisting vacuum tubes ond valves. This has taken over by sernicor-,ductor and transistors which were 0' smaller size and more efficient. The rapid growth in the semiconductor industry hos led to the present form computer on our desktop. This hos initiated the questions about the ultimate limit of this development. AS size Of computer chip is decreasing, if has been predicted by Moor's law that within next twenty year, the size Of a sing bit will be of the order of a single atom. Physical laws governing the atomic phenomena, such cs quantum mechanics, are very different from macroscopic laws. so the computers operating on atomic level will not be Same cs pæsent days computers. This possibility has openee c completely new field of Quantum Computation.

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Approaching Single Atom Detection with Atomic Fluorescence in a Glow Discharge Atom Reservoir

Applied Spectroscopy ◽

10.1366/0003702894202148 ◽

1989 ◽

Vol 43 (5) ◽

pp. 873-876 ◽

Cited By ~ 33

Author(s):

B. W. Smith ◽

J. B. Womack ◽

N. Omenetto ◽

J. D. Winefordner

Keyword(s):

Detection Limit ◽

Glow Discharge ◽

Laser Beam ◽

Hollow Cathode ◽

Single Atom ◽

Atomic Fluorescence ◽

Discharge Source ◽

Atom Detection ◽

Atomization Characteristics ◽

Glow Discharge Source

A commercial hollow cathode lamp is used as an atom reservoir for the atomic fluorescence of lead excited by a copper laser pumped dye laser. The glow discharge source is nearly an ideal atom cell for such measurements, having very low background emission and excellent atomization characteristics. A detection limit of 1.8 ag of lead within the laser beam is easily obtained.

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Coherent excitation of a single atom to a Rydberg state

Physical Review A ◽

10.1103/physreva.82.013405 ◽

2010 ◽

Vol 82 (1) ◽

Cited By ~ 35

Author(s):

Y. Miroshnychenko ◽

A. Gaëtan ◽

C. Evellin ◽

P. Grangier ◽

D. Comparat ◽

...

Keyword(s):

Rydberg State ◽

Single Atom ◽

Coherent Excitation

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Velocity-dependent optical forces and Maxwell’s demon

Scientific Reports ◽

10.1038/s41598-019-50284-z ◽

2019 ◽

Vol 9 (1) ◽

Author(s):

J. D. Franson

Keyword(s):

Quantum Information ◽

Laser Beam ◽

Optical Tweezers ◽

Optical Forces ◽

Velocity Dependence ◽

Photon Scattering ◽

Maxwell’S Demon ◽

Maxwell's Demon ◽

Dipole Force ◽

The Doppler Effect

Abstract An atom placed in a focused laser beam will experience a dipole force due to the gradient in the interaction energy, which is analogous to the well-known optical tweezers effect. This force will be dependent on the velocity of the atom due to the Doppler effect, which could potentially be used to implement a Maxwell’s demon. Photon scattering and other forms of dissipation can be negligibly small, which would seem to contradict quantum information proofs that a Maxwell’s demon must dissipate a minimum amount of energy. We show that the velocity dependence of the dipole force is cancelled out by another force that is related to the gradient in the phase of the laser beam. As a result, a Maxwell’s demon cannot be implemented in this way.

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