a Graduate School of Humanities and Sciences, Ochanomizu University, 2-1-1 Ohtsuka, Bunkyo-ku, Tokyo 112-8610, Japan b International Christian University, 3-10-2 Osawa, Mitaka, Tokyo 181-8585, Japan
Abstract:
It is shown that the dephasing of a qubit caused by a Markov process can be suppressed by a successive application of π-pulses if two-time conditional probability of the stochastic variable depends only on the time-difference. The several types of the π-pulse sequence are compared in the case of the two-state jump Markov process.