Experimental demonstration of quantum transport enhancement using time-reversal symmetry breaking on a silicon photonic chip

The continuous-time quantum walk is a basic model for studying transport and developing quantum-enhanced algorithms. Recent studies show that by introducing phase into the standard model, time-reversal symmetry can be broken without changing Hermitian property of Hamiltonian. breaking shows advantages in transport, such as perfect state transfer, directional control, speedup, efficiency enhancement. In this work, we implement walks on reconfigurable silicon photonic chip demonstrate enhancement introduced symmetry. Perfect transfer three-site ring, switch implemented six-site graph, speedup using linear chain triangles are demonstrated with high fidelity. Time-reversal asymmetry has also been used simplified light-harvesting implying potential photosynthesis investigations.