Physical Implementation of Quantum Random Walks

          @misc{ pirsa_PIRSA:09050015,
            doi = {10.48660/09050015},
            url = {https://pirsa.org/09050015},
            author = {Wang, Jingbo},
            keywords = {Quantum Information},
            language = {en},
            title = {Physical Implementation of Quantum Random Walks},
            publisher = {Perimeter Institute},
            year = {2009},
            month = {may},
            note = {PIRSA:09050015 see, \url{https://pirsa.org}}
          }
          

Abstract

Quantum random walks have received much interest due to their non- intuitive dynamics, which may hold a key to radically new quantum algorithms. What remains a major challenge is a physical realization that is experimentally viable, readily scalable, and not limited to specific connectivity criteria. In this seminar, I will present an implementation scheme for quantum walking on arbitrarily complex graphs. This scheme is particularly elegant since the walker is not required to physically step between the nodes; only flipping coins is sufficient. In addition, by taking advantage of the inherent structure of the CS decomposition of unitary matrices, we are able to implement all coin operations necessary for each step of the walk simultaneously. This scheme can be physically realized using a variety of quantum systems, such as cold atoms trapped inside an optical lattice or electrons inside coupled quantum dots.