Parametric fluctuations or stochastic signals are introduced into the control
pulse sequence to investigate the feasibility of random control over quantum
open systems. In a large parameter error region, the out-of-order control
pulses work as well as the regular pulses for dynamical decoupling and
dissipation suppression. Calculations and analysis are based on a
non-perturbative control approach allowed by an exact quantum-state-diffusion
equation. When the average frequency and duration of the pulse sequence take
proper values, the random control sequence is robust, fault- tolerant, and
insensitive to pulse strength deviations and interpulse temporal separation in
the quasi-periodic sequence. This relaxes the operational requirements placed
on quantum control experiments to a great deal.Comment: 7 pages, 6 firgure