Complementarity and quantum walks

Viv Kendon, Barry C. Sanders
2005 Physical Review A. Atomic, Molecular, and Optical Physics  
We show that quantum walks interpolate between a coherent 'wave walk' and a random walk depending on how strongly the walker's coin state is measured; i.e., the quantum walk exhibits the quintessentially quantum property of complementarity, which is manifested as a trade-off between knowledge of which path the walker takes vs the sharpness of the interference pattern. A physical implementation of a quantum walk (the quantum quincunx) should thus have an identifiable walker and the capacity to
more » ... monstrate the interpolation between wave walk and random walk depending on the strength of measurement.
doi:10.1103/physreva.71.022307 fatcat:owboquhhebfetmqtx5czosgjti