**46**, 359-363 (2008)

https://doi.org/10.1140/epjd/e2007-00304-5

## Amplitude-squared squeezing in superposed coherent states

^{1}
Department of Physics, University of Allahabad, Allahabad, 211002, India

^{2}
M.N. Saha Centre of Space Studies, Institute of Interdisciplinary Studies, University of Allahabad, Allahabad, 211002, India

^{3}
Bhavan's Mehta Mahavidyalaya (V.S. Mehta College of Science), Bharwari, Kaushambi, 212201, India

Corresponding authors: ^{a}
prakash_hari123@rediffmail.com
- ^{b}
pankaj_k25@rediffmail.com

Received:
12
June
2007

Revised:
31
August
2007

Published online:
31
October
2007

We study amplitude-squared squeezing of the Hermitian operator Z_{θ}=Z_{1}
cosθ+Z_{2} sin θ, in the most general superposition state
, of two coherent states
and . Here operators Z_{1,2 } are defined by
, a is annihilation operator, θ is angle, and
complex numbers C_{1,2 }, α, β are arbitrary and only
restriction on these is the normalization condition of the state . We define the condition for a state to be amplitude-squared squeezed for the operator Z_{θ
} if squeezing parameter , where N=a^{+}a and . We find
maximum amplitude-squared squeezing of Z_{θ} in the superposed
coherent state with minimum value 0.3268 of the
parameter S for an infinite combinations with α- β= 2.16
exp [±i(π/4) + iθ/2], and with
arbitrary values of (α+β) and θ. For this minimum
value of squeezing parameter S, the expectation value of photon number can
vary from the minimum value 1.0481 to infinity. Variations of the parameter
S with different variables at maximum amplitude-squared squeezing are also
discussed.

PACS: 42.50.Dv – Nonclassical states of the electromagnetic field, including entangled photon states; quantum state engineering and measurements

*© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2007*