Experimental protection and revival of quantum correlation in open solid systems
Xing Rong, Fangzhou Jin, Zixiang Wang, Jianpei Geng, Chenyong Ju, Ya Wang, Runmin Zhang, Chang‐Kui Duan, Mingjun Shi, Jiangfeng Du · Physical Review B · 2013
Quantum correlations quantified by quantum discord have been experimentally demonstrated as important physical resources in quantum information processing. Because of the inevitable interactions between the quantum system and the environment, it is essential to characterize the quantum correlation's dynamics in open systems and to protect the quantum correlation from being lost in the environment. Herein it is experimentally demonstrated in the Si:P system that there is a sudden change (at a critical time ${t}_{c}\ensuremath{\approx}166$ ns) in the decay rates of classical and quantum correlations. To protect the quantum correlation, we achieve an extension of the critical time by 50 times to $8\phantom{\rule{0.28em}{0ex}}\ensuremath{\mu}$s by applying a two-flip dynamical decoupling pulse sequence. Moreover, we observe the phenomenon of the revival of both quantum and classical correlations. The experimental observation of a nondecay interval for quantum correlation and its great extension in a solid-state system with genuine noise makes the use of quantum discord as a physical resource in quantum information processing more practicable.