Experimental optimal generation of hybrid entangled states in photonic quantum walks

While the existence of disorders is commonly believed to weaken the unique properties of quantum systems, recent progress has predicted that it can exhibit a counterintuitive enhanced effect on the behavior of entanglement generation, which is even independent of the chosen initial conditions and physical platforms. However, to achieve a maximally entangled state in such disordered quantum systems, the key limitation of this is the scarcity of an infinite coherence time, which makes its experimental realization challenging. Here, we experimentally investigate the entanglement entropy dynamics in a photonic quantum walk with disorders in time. Through the incorporation of a classic optimization algorithm, we experimentally demonstrate that such disordered systems can relax to a high-entanglement hybrid state at any given time step. Moreover, this prominent entangling ability is universal for a wide variety of initial conditions. Our results may inspire achieving a well-controlled entanglement generator for quantum computation and information tasks. (C) 2021 Optical Society of America

Automated summary

Recent research has shown that disorders in quantum systems may have an enhanced effect on entanglement generation, independent of initial conditions and physical platforms. The challenge lies in achieving maximal entanglement due to the limited coherence time in disordered quantum systems. Through classic optimization algorithms, high-entanglement hybrid states can be achieved at any given time step, inspiring the development of well-controlled entanglement generators for quantum computation and information tasks.