  A behavior of quantum states (superposition of two lowest eigenstates,
Gaussian wave packet) in phase space is studied for one and two dimensional
double well potential. Two dimensional potential is constructed from double
well potential coupled linearly and quadratically to harmonic potential.
Quantum trajectories are compared with classical ones. Preferable tunneling
path in phase space is found. An influence of energy of initial Gaussian wave
packet and trajectory initial condition on tunneling process is analyzed..
Coupling effect on trajectories and preferable tunneling path for two
dimensional potential is studied.
