title: Ultrafast all-optical switching based on cross modulation utilizing intersubband transitions in InGaAs/AlAs/AlAsSb coupled quantum wells with DFB grating waveguides.
abstract: A distributed feedback Bragg grating waveguide all-optical switch design relying on the ultrafast cross modulation effect of the intersubband transitions in InGaAs/AlAs/AlAsSb coupled double quantum wells is demonstrated. The pump-induced phase modulation to the signal light is converted to intensity modulation efficiently on chip with the help of the grating structures. To our best knowledge, the switching dynamic characteristics of such design are reported for the first time. With a 400 μm long grating waveguide, 3 dB modulation depth with switching energy of 5.5 pJ and recovery time of 4.5 ps is obtained for the switch-off operation.
authors.affiliation: Electronics Laboratory, ETH Zürich, 8092 Zürich, Switzerland. pingma@ife.ee.ethz.ch
authors.forename: Ping
authors.initials: P
authors.lastname: Ma
authors.forename: Yuriy
authors.initials: Y
authors.lastname: Fedoryshyn
authors.forename: Heinz
authors.initials: H
authors.lastname: Jäckel