Physical Review A
Orthonormalized eigenstates of the quantum operator ak and their nonclassical properties
Xiao-Ming Liu, Shun-Jin Wang, ZHANG WEN-ZHONG
Abstract
A method for construction of the k orthonormalized quantum eigenstates of the higher powers ${\mathit{a}}^{\mathit{k}}$ of the quantum-annihilation operator a is proposed, and their physical meaning is explored. Nonclassical properties of these quantum eigenstates are studied and the main results are as follows: (1) All of the eigenstates can be expressed as a linear superposition of k quantum-coherent states; (2) all of them are generalized quantum-coherent states; (3) for k\ensuremath{\ge}3, they have the Nth-order quantum squeezing for N=mk+k/2 (m=0,1,2, . . .) and even k, but no Nth-order quantum squeezing for other values of N and k; (4) for k\ensuremath{\ge}3, all of them exhibit the lowest- and higher-order quantum antibunching.