Superpositions of excited-deexcited coherent states and some of their non-classical properties

Applying the opera,tor a+a(+) to the superposed coherent states several times, superpositions of the excited-deexcited coherent states are obtained. Compared with the original superposed coherent states, these new states can have stronger squeezing and anti-bunching effects. The operation a+a(+) can also induce squeezing or antibunching effect if the original states do not possess these properties. Calculations about the phase properties, the Q function and the Wigner function reflect the non-classical character of the excited-deexcited states from different aspects. (C) 2013 Elsevier GmbH. All rights reserved.