A comparison between the performance of number-state and coherent-state optical CDMA in lossy photon channels

We obtained the uncertainty relation in squeezed states for a time-dependent oscillator. The uncertainty relation in coherent states is same as that of the number states with n=0. However, the uncertainty relation in squeezed states does not satisfy this property and depends on squeezing parameter c. For instance, the uncertainty relation is ℏ/2 which is the minimum value as far as quantum mechanics permits for c=1, same as that in coherent state for c=±∞, and infinity for c=-1. If the time-dependency of the Hamiltonian for the system vanishes, the uncertainty relation in squeezed states will no longer depend on c and becomes the same as that in number state with n=0, like the uncertainty relation in coherent states.

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Expansion coefficients of a squeezed coherent state in the number state basis

American Journal of Physics ◽

10.1119/1.16337 ◽

1990 ◽

Vol 58 (10) ◽

pp. 1003-1006 ◽

Cited By ~ 14

Author(s):

J. J. Gong ◽

P. K. Aravind

Keyword(s):

Coherent State ◽

Number State ◽

Squeezed Coherent State ◽

Expansion Coefficients

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Quantum interferometry via a coherent state mixed with a squeezed number state

Chinese Physics B ◽

10.1088/1674-1056/28/4/044203 ◽

2019 ◽

Vol 28 (4) ◽

pp. 044203 ◽

Cited By ~ 1

Author(s):

Li-Li Hou ◽

Yong-Xing Sui ◽

Shuai Wang ◽

Xue-Fen Xu

Keyword(s):

Coherent State ◽

Number State ◽

Quantum Interferometry

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ENTANGLEMENT AND PHOTON DYNAMICS IN THE INTERACTION BETWEEN TWO QUANTIZED ELECTROMAGNETIC FIELDS AND 3-LEVEL ATOMS

International Journal of Quantum Information ◽

10.1142/s0219749911006703 ◽

2011 ◽

Vol 09 (01) ◽

pp. 593-605 ◽

Cited By ~ 1

Author(s):

B. VASEGHI ◽

G. REZAEI ◽

R. KHORDAD ◽

A. FALLAH ZADEH

Keyword(s):

Coherent State ◽

Electromagnetic Fields ◽

Atomic System ◽

Single Mode ◽

The Other ◽

Level Atom ◽

Number State ◽

Fock State ◽

The Mean ◽

Degree Of Entanglement

We study in this paper the dynamics of two electromagnetic (EM) fields and their entanglement in the interaction with a 3-level atom (Λ-configuration). We investigate the interaction when initially one of the fields is in a single mode coherent state, and the other one is in a Fock(number) state. We have calculated the mean photon numbers of the fields and their entanglement by means of the fields entropy as a measure of it. The results show the synchronization between entanglement beats and collapses-revivals of the fields, which cause the field in the Fock state (noncoherent) to behave coherently during the interaction. Also the results offer a way to generate coherent fields and achieve any desired degree of entanglement with specified dynamics via controlling the parameters of the atomic system.

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