Experimental protection and revival of quantum correlation in open solid systems

TL;DR

This paper demonstrates the experimental preservation and revival of quantum discord in a solid-state system, extending its stable duration significantly through dynamical decoupling, thus enhancing its potential as a resource in quantum information processing.

Contribution

It provides the first experimental evidence of a stable quantum correlation interval and its revival in a solid-state system under realistic noise conditions.

Findings

Quantum discord remains stable until a critical time of 166 ns.

Dynamical decoupling extends the quantum correlation lifetime to 8 microseconds.

Revival of quantum and classical correlations observed in the system.

Abstract

Quantum correlation quantified by quantum discord has been demonstrated experimentally as important physical resources in quantum computation and communication for some cases even without the presence of entanglement. However, since the interaction between the quantum system and the noisy environment is inevitable, it is essential to protect quantum correlation from lost in the environment and to characterize its dynamical behavior in the real open systems. Here we showed experimentally in the solid-state P:Si system the existence of a stable interval for the quantum correlation in the beginning until a critical time $t_c \approx 166$ ns of the transition from classical to quantum decoherence. To protect the quantum correlation, we achieved the extension of the critical time by 50 times to $8 \mu$s by applying a two-flip dynamical decoupling (DD) pulse sequence. Moreover, we observed the phenomenon of the revival of quantum correlation, as well as classical correlation. The experimental observation of a non-decay interval for quantum correlation and the great extension of it in an important solid-state system with genuine noise makes the use quantum discord as physical resources in quantum information processing more practicable.