| 摘要 |
<p>PURPOSE:To obtain an optical bistable element which can make high-speed operation without using a resonator by using quantum well structure into which a carrier is injected and making light of the low energy in the range when the coefft. of absorption increases with an increase in carrier density incident on said structure from the absorption end of the quantum well thereby operating the same. CONSTITUTION:The optical bistable element 1 of 20mum length is constituted of the structure in which a quantum well waveguide layer 11 consisting of a quantum well of GaAs/Al0.2Ga0.8As having 110Angstrom well width, as well as a p clad layer 12 and n clad layer 13 consisting of Ga0.6Al0.4As are embedded with an n<-> embedding layer 17 and p<-> embedding layer 18 consisting of Ga0.7 Al0.3As. The absorption ends of such quantum well exists at 1.47eV, but when the carrier density of the quantum well is made 1.0X10<12>cm<-2> by injecting current thereto from electrodes 15, 16, the coefft. of absorption at which the carrier density increases with the light of 1.456eV energy increases and the optical bistability is obtd. The optical bistable element which can make high- speed operation is thus obtd. without the need for a resonator.</p> |
