A NEW TYPE OF q-COHERENT STATES AND ITS APPLICATIONS

In this letter, a new type of q-coherent states with M components is introduced. Some properties of the q-coherent state are discussed. The cycle representations of quantum algebra SU q(2) are obtained by means of the two-mode q-coherent states.

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Modified photon-added coherent states: Generation and relatedentangled states

Canadian Journal of Physics ◽

10.1139/p08-088 ◽

2008 ◽

Vol 86 (12) ◽

pp. 1387-1392 ◽

Cited By ~ 4

Author(s):

M -L Liang ◽

J -N Zhang ◽

B Yuan

Keyword(s):

Coherent State ◽

Radiation Field ◽

Coherent States ◽

Hermitian Operator ◽

Field Interaction ◽

Wave Approximation ◽

New Type ◽

The One ◽

Entangled Coherent States ◽

03.65 Ud

We construct one new type of quantum state that we call the modified photon-added coherent state (MPACS) of the radiation field. These states are created by repeatedly applying the Hermitian operator (a + a+) to the coherent state m times. It turns out that these states are the superpositions of the coherent and the photon-added coherent states, and have highly nonclassical behavior depending on the excitation m and other parameters. The one-mode and two-mode modified entangled coherent states are also studied. MPACS can be generated through the atom-field interaction under the nonrotating wave approximation. PACS Nos.: 42.50.Dv, 03.65.Ca, 03.65.Ud

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The Two-Variable Coherent States of the Quantum Algebra su q (1,1)

Communications in Theoretical Physics ◽

10.1088/0253-6102/28/2/231 ◽

1997 ◽

Vol 28 (2) ◽

pp. 231-236

Author(s):

Gong Renshan

Keyword(s):

Coherent States ◽

Quantum Algebra

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INTERACTION OF MESOSCOPIC JOSEPHSON JUNCTION WITH A SUCCESSIVE SQUEEZED COHERENT FIELD

Modern Physics Letters B ◽

10.1142/s021798490000077x ◽

2000 ◽

Vol 14 (16) ◽

pp. 609-618

Author(s):

V. A. POPESCU

Keyword(s):

Coherent State ◽

Josephson Junction ◽

Coherent States ◽

Quantum Noise ◽

Shapiro Steps ◽

Superconducting Ring ◽

Coherent Field ◽

Current Voltage ◽

Quantum Current ◽

The Difference

Signal-to-quantum noise ratio for quantum current in mesoscopic Josephson junction of a circular superconducting ring can be improved if the electromagnetic field is in a successive squeezed coherent state. The mesoscopic Josephson junctions can feel the difference between the successive squeezed coherent states and other types of squeezed coherent states because their current–voltage Shapiro steps are different. We compare our method with another procedure for superposition of two squeezed coherent states (a squeezed even coherent state) and consider the effect of different large inductances on the supercurrent.

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Common Coherence Witnesses and Common Coherent States

Entropy ◽

10.3390/e23091136 ◽

2021 ◽

Vol 23 (9) ◽

pp. 1136

Author(s):

Bang-Hai Wang ◽

Zi-Heng Ding ◽

Zhihao Ma ◽

Shao-Ming Fei

Keyword(s):

Coherent State ◽

Coherent States ◽

State Problem ◽

Properties And Characterization ◽

The Common ◽

High Level

We show the properties and characterization of coherence witnesses. We show methods for constructing coherence witnesses for an arbitrary coherent state. We investigate the problem of finding common coherence witnesses for certain class of states. We show that finitely many different witnesses W1,W2,⋯,Wn can detect some common coherent states if and only if ∑i=1ntiWi is still a witnesses for any nonnegative numbers ti(i=1,2,⋯,n). We show coherent states play the role of high-level witnesses. Thus, the common state problem is changed into the question of when different high-level witnesses (coherent states) can detect the same coherence witnesses. Moreover, we show a coherent state and its robust state have no common coherence witness and give a general way to construct optimal coherence witnesses for any comparable states.

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Basis set sampling in the method of coupled coherent states: Coherent state swarms, trains, and pancakes

The Journal of Chemical Physics ◽

10.1063/1.2828509 ◽

2008 ◽

Vol 128 (5) ◽

pp. 054102 ◽

Cited By ~ 55

Author(s):

Dmitrii V. Shalashilin ◽

Mark S. Child

Keyword(s):

Coherent State ◽

Coherent States ◽

Basis Set

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Binary Communication with Gazeau–Klauder Coherent States

Entropy ◽

10.3390/e22020201 ◽

2020 ◽

Vol 22 (2) ◽

pp. 201

Author(s):

Jerzy Dajka ◽

Jerzy Łuczka

Keyword(s):

Coherent State ◽

Optical Communication ◽

Coherent States ◽

Error Probability ◽

Nonlinear Oscillator ◽

Short Paper ◽

Trace Distance ◽

Advantages And Disadvantages

We investigate advantages and disadvantages of using Gazeau–Klauder coherent states for optical communication. In this short paper we show that using an alphabet consisting of coherent Gazeau–Klauder states related to a Kerr-type nonlinear oscillator instead of standard Perelomov coherent states results in lowering of the Helstrom bound for error probability in binary communication. We also discuss trace distance between Gazeau–Klauder coherent states and a standard coherent state as a quantifier of distinguishability of alphabets.

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Teleporting the Schrödinger Cat State

Modern Physics Letters B ◽

10.1142/s0217984998001438 ◽

1998 ◽

Vol 12 (29n30) ◽

pp. 1209-1216 ◽

Cited By ~ 6

Author(s):

M. H. Y. Moussa ◽

B. Baseia

Keyword(s):

Coherent State ◽

Quantum Channel ◽

Coherent States ◽

Joint Measurement ◽

Bell Basis ◽

Schrödinger Cat ◽

Schrodinger Cat State

We present a scheme for the teleportation of a coherent state or a mesoscopic superposition of coherent states — the Schrödinger-cat state. The proposal involves a mesoscopic-correlated state as the quantum channel which is generated through an adaptation of a quantum switch scheme. The required joint measurement performed in a mesoscopic Bell basis is accomplished through a technique for detection of a Schrödinger-cat state "trapped" in a cavity.

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On the Squeezing and Displacement of nth-Order

Modern Physics Letters B ◽

10.1142/s0217984997000499 ◽

1997 ◽

Vol 11 (09n10) ◽

pp. 399-406

Author(s):

Norton G. de Almeida ◽

Célia M. A. Dantas

Keyword(s):

Coherent State ◽

Coherent States ◽

Photon Number ◽

Natural Generalization ◽

Statistical Properties ◽

Number Distribution ◽

Quantum Statistical ◽

Photon Number Distribution

The norder expressions for the squeezed and coherent states are derived as a natural generalization of the usual squeezed coherent and coherent states. The photon number distribution of n order of squeezed coherent states that are eigenstates of the operators [Formula: see text] is derived. The n order coherent state is a particular case of the states that we are now deriving. Some mathematical and quantum statistical properties of these states are discussed.

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COHERENT STATES WITHOUT GROUPS: QUANTIZATION ON NONHOMOGENEOUS MANIFOLDS

Modern Physics Letters A ◽

10.1142/s021773239300146x ◽

1993 ◽

Vol 08 (18) ◽

pp. 1735-1738 ◽

Cited By ~ 18

Author(s):

JOHN R. KLAUDER

Keyword(s):

Phase Space ◽

Coherent State ◽

Wide Class ◽

Coherent States ◽

Path Integrals ◽

Killing Vector ◽

Single Variable ◽

Holomorphic Representation ◽

Representation Spaces ◽

State Path

A wide class of single-variable holomorphic representation spaces are constructed that are associated with very general sets of coherent states defined without the use of transitively acting groups. These representations and states are used to define coherent-state path integrals involving phase-space manifolds having one Killing vector but a quite general curvature otherwise.

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The influence of excitation number of photon-added coherent state field on the entanglement swapping process

International Journal of Modern Physics B ◽

10.1142/s0217979217501983 ◽

2017 ◽

Vol 31 (27) ◽

pp. 1750198 ◽

Cited By ~ 3

Author(s):

M. Soltani ◽

M. K. Tavassoly ◽

R. Pakniat

Keyword(s):

Coherent State ◽

Quantum Electrodynamics ◽

Coherent States ◽

Success Probability ◽

Entanglement Swapping ◽

Cavity Quantum Electrodynamics ◽

Linear Entropy ◽

Entangled State ◽

Maximally Entangled State ◽

Coherent Field

In this paper, we outline a scheme for the entanglement swapping procedure based on cavity quantum electrodynamics using the Jaynes–Cummings model consisting of the coherent and photon-added coherent states. In particular, utilizing the photon-added coherent states ([Formula: see text][Formula: see text][Formula: see text][Formula: see text], where [Formula: see text] is the Glauber coherent state) in the scheme, enables us to investigate the effect of [Formula: see text], i.e., the number of excitations corresponding to the photon-added coherent field on the entanglement swapping process. In the scheme, two two-level atoms [Formula: see text] and [Formula: see text] are initially entangled together, and distinctly two exploited cavity fields [Formula: see text] and [Formula: see text] are prepared in an entangled state (a combination of coherent and photon-added coherent states). Interacting the atom [Formula: see text] with field [Formula: see text] (via the Jaynes–Cummings model) and then making detection on them, transfers the entanglement from the two atoms [Formula: see text], [Formula: see text] and the two fields [Formula: see text], [Formula: see text] to the atom-field “[Formula: see text]-[Formula: see text]”, i.e., entanglement swapping occurs. In the continuation, we pay our attention to the evaluation of the fidelity of the swapped entangled state relative to a suitable maximally entangled state, success probability of the performed detections and linear entropy as the degree of entanglement of the swapped entangled state. It is demonstrated that, an increase in the number of excitations, [Formula: see text], leads to the increment of fidelity as well as the amount of entanglement. According to our numerical results, the maximum values of fidelity (linear entropy) 0.98 (0.46) is obtained for [Formula: see text], however, the maximum value of success probability does not significantly change by increasing [Formula: see text].

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