Non-Destructive Discrimination of arbitrary set of orthogonal quantum   states by NMR using Quantum Phase Estimation
  An algorithm based on quantum phase estimation, which discriminates quantum states nondestructively within a set of arbitrary orthogonal states, is described and experimentally verified by a NMR quantum information processor. The procedure is scalable and can be applied to any set of orthogonal states. Scalability is demonstrated through Matlab simulation. 
V S Manu and Anil Kumar
quant-ph