Quantum Walks with Dynamical Control: Graph Engineering, Initial State   Preparation and State Transfer
  Quantum walks are a well-established model for the study of coherent transport phenomena and provide a universal platform in quantum information theory. Dynamically influencing the walker's evolution gives a high degree of flexibility for studying various applications. Here, we present time-multiplexed finite quantum walks of variable size, the preparation of non-localized input states and their dynamical evolution. As a further application, we implement a state transfer scheme for an arbitrary input state to two different output modes. The presented experiments rely on the full dynamical control of a time-multiplexed quantum walk, which includes adjustable coin operation as well as the possibility to flexibly configure the underlying graph structures. 
Thomas Nitsche, Fabian Elster, Jaroslav Novotn\'y, Aur\'el G\'abris,   Igor Jex, Sonja Barkhofen, Christine Silberhorn
quant-ph