Patent ID: 8774572
Filing Date: 2014-07-08
Classification: G02F,H01S

Abstract:
1. A bistable element comprising: a multi-mode interference optical waveguide provided on a substrate, and having a number M of ports formed in one end face thereof (M is integers more than one), and a number N of ports formed in another end face (N is integers more than zero, and less than M or equal to M); a first group of optical waveguides provided on said substrate, and including a number M of optical waveguides, each of which has one end face connected to a corresponding port formed in the one end face of said multi-mode interference optical waveguide; and a second group of optical waveguides provided on said substrate, and including a number N of optical waveguides, each of which has one end face connected to a corresponding port formed in the other end face of said multi-mode interference optical waveguide, characterized by the fact that said multi-mode interference optical waveguide includes a saturable absorbing region in which saturation in an amount of absorbed light is caused by the fact that an absorbing coefficient is reduced as an intensity of incident light becomes larger.