Continuous quantum feedback of coherent oscillations in a solid-state   qubit
  We have analyzed theoretically the operation of the Bayesian quantum feedback of a solid-state qubit, designed to maintain perfect coherent oscillations in the qubit for arbitrarily long time. In particular, we have studied the feedback efficiency in presence of dephasing environment and detector nonideality. Also, we have analyzed the effect of qubit parameter deviations and studied the quantum feedback control of an energy-asymmetric qubit. 
Qin Zhang, Rusko Ruskov, and Alexander N. Korotkov