Experimental realization of a generalized measuring device via a   one-dimensional photonic quantum walk
  We demonstrate an implementation of unambiguous state discrimination of two equally probable single-qubit states via a one-dimensional photonic quantum walk experimentally. Furthermore we experimentally realize a quantum walk algorithm for implementing a generalized measurement in terms of positive operator value measurement on a single qubit. The measurement of the single-photons' positions corresponds to a measurement of an element of the positive operator value measurement on the polarizations of the single-photons. 
Zhihao Bian, Rong Zhang, Hao Qin, Xiang Zhan, Jian Li, and Peng Xue
quant-ph