Naoya TATE and Jun TANIDA

Department of Information and Physical Sciences, Graduate School of Information Science and Technology, Osaka University, 2-1 Yamadaoka Suita, Osaka 565-0871, Japan

(Received June 2, 2003; Accepted January 19, 2004)

Several implementations of quantum computation making effective use of the quantum behavior of single-photons have been explored. These implementing methods were found unsuitble for large-scale computation, because they require 2^N-1 optical paths to represent N qubits. In this paper, a new computing scheme is described which utilizes spatial distribution of photons. The occupation of several optical paths by single-photons is adopted as qubits. This adoption gives several extension of processing capacity and computational functionality with a simple setup. An optical implementation of a solution algorithm on four-bit Deutsch-Jozsa problem is demonstrated with utilization of the spatial distribution of photons.

Key words: quantum computing, single-photon, Deutsch-Jozsa problem