(英) |
Quantum walk is a quantum version of random walk and is expected to have applications in quantum simulation and quantum computation. Using photons, the unitary transformations required for quantum walks are relatively easy to realize. Therefore, many experiments of quantum walks have been performed using photons. However, almost all experiments have been carried out under absorbing boundary conditions, where photons are lost at the boundaries. Hence, we aim to realize a two-dimensional quantum walk with new boundary conditions keeping photons in the system, called helical boundary conditions. Two-dimensional quantum walks with helical boundary conditions have translation invariance and are expected to have attractive applications such as novel kinds of quantum simulations and implementation of quantum search algorithms. In this study, we propose a method to implement a photonic quantum walk with helical boundary conditions, and report on the generation and evaluation of light with petal-shaped spatial modes which is the key to its realization. |