Exact wave functions and coherent states for a forced damped harmonic oscillator

The exact wave function ψnz(t) (x, t) of Schr\:odinger equation for a forced damped harmonic oscillator is obtained using transformation of variables and factorization of a wave function, where suffix n takes values 0, 1,2, … The mean value of the position or momentum satisfies the classical equation of motion. The uncertainty of position or momentum is related to time and independent of an external force, but their product being independent of time. When n = 0, ψnz(t) (x,t) expresses both the coherent states for a forced damped harmonic oscillator and the squeezed coherent states for a standard harmonic oscillator.