Abstract
Low-decoherence regime plays a key role in constructing multi-particle quantum systems and has therefore been constantly pursued in order to build quantum simulators and quantum computers in a scalable fashion. Quantum error correction and quantum topological computing have been proved being able to protect quantumness but haven't been experimentally realized yet. Recently, topological boundary states are found inherently stable and are capable of protecting physical fields from dissipation and disorder, which inspires the application of such a topological protection on quantum correlation. Here, we present an experimental demonstration of topological protection of two-photon quantum states on a photonic chip. By analyzing the quantum correlation of photons out from the topologically nontrivial boundary state, we obtain a high cross-correlation and a strong violation of Cauchy-Schwarz inequality up to 30 standard deviations. Our results, together with our integrated implementation, provide an alternative way of protecting quantumness, and may inspire many more explorations in 'quantum topological photonics', a crossover between topological photonics and quantum information.
Highlights
Low-decoherence regime plays a key role in constructing multi-particle quantum systems and has been constantly pursued in order to build quantum simulators and quantum computers in a scalable fashion
Two-particle quantum walk can be an algorithmic tool for the graph isomorphism problem [8], and the universal computation can be achieved by multiparticle quantum walk efficiently [9]
Quantum error correction is proposed to preserve logical quantum states in a subspace and rectify errors according to the measurement outcomes of ancillary particles [10, 11]
Summary
Low-decoherence regime plays a key role in constructing multi-particle quantum systems and has been constantly pursued in order to build quantum simulators and quantum computers in a scalable fashion. Together with the integrability and controllability of integrated photonic chip [8, 26], the on-chip topological boundary states may provide an alternative way of protecting quantumness effectively. We experimentally investigate the evolution dynamics and their preservation of two-photon quantum correlated states in the topological photonic lattice on a photonic chip.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
