TY - DATA T1 - Fidelity evolution of the single-qutrit dephasing model under a 20 control-pulse UDD sequence with different environment memory parameter γ PY - 2013/08/27 AU - Wenchong Shu AU - Xinyu Zhao AU - Jun Jing AU - Lian-Ao Wu AU - Ting Yu UR - https://iop.figshare.com/articles/figure/_Fidelity_evolution_of_the_single_qutrit_dephasing_model_under_a_20_control_pulse_UDD_sequence_with_/1012652 DO - 10.6084/m9.figshare.1012652.v1 L4 - https://ndownloader.figshare.com/files/1480475 KW - time points KW - control fields KW - udd KW - control pulses KW - amplitude noises KW - control dynamics KW - freedom KW - control efficacy KW - QSD approach KW - Trotter product formula KW - control operators KW - quantum systems KW - environment memory time KW - rangle KW - sequence KW - quantum state diffusion KW - equation KW - Atomic Physics KW - Molecular Physics N2 - Figure 2. Fidelity evolution of the single-qutrit dephasing model under a 20 control-pulse UDD sequence with different environment memory parameter γ. The initial state |\psi _0\rangle =\frac{1}{\sqrt{3}}(|0\rangle +|1\rangle +|2\rangle ). Abstract In this paper, we use the quantum state diffusion (QSD) equation to implement the Uhrig dynamical decoupling to a three-level quantum system coupled to a non-Markovian reservoir comprising of infinite numbers of degrees of freedom. For this purpose, we first reformulate the non-Markovian QSD to incorporate the effect of the external control fields. With this stochastic QSD approach, we demonstrate that an unknown state of the three-level quantum system can be universally protected against both coloured phase and amplitude noises when the control-pulse sequences and control operators are properly designed. The advantage of using non-Markovian QSD equations is that the control dynamics of open quantum systems can be treated exactly without using Trotter product formula and be efficiently simulated even when the environment is comprised of infinite numbers of degrees of freedom. We also show how the control efficacy depends on the environment memory time and the designed time points of applied control pulses. ER -