Abstract

This paper studies a new method to generate a three-photon entangled state. The entangled three-photon state is created by using the idler from two independent spontaneous downcon-versions (SPDC) to generate a third beam by sum frequency generation (SFG) or upconver-sion. The two signal photons along with the upconverted photon form the three-photon entangled state, or triphoton (Fig. 1). The quantum mechanical development provided here follows that found in Rubin et al.¹ and Keller and Rubin².

© 1998 Optical Society of America