title: High-Q-preserving coupling between a spiral and a semicircle micro-cavity.
abstract: We present an efficient design for direct coupling between a spiral-shaped and a semicircle-shaped microcavity (micro-cavity) as an alternative to traditional evanescent wave coupling for planar integrated photonic technology. We observe the preservation of the high Q-value of the spiral oscillator when coupled to a semicircle under current injection using an AlGaAs single-quantum-well heterostructure. With slight alterations to the directly coupled micro-cavity configuration, such as coupling shape and overlap distance, the number of observed modes and output intensity are changed. AlGaAs and InGaN spiral-shaped microcavities have unidirectional emission normal to the spiral notch.
authors.affiliation: Department of Applied Physics, Yale University, CT 06520, USA. gracehern@yahoo.com
authors.forename: G D
authors.initials: GD
authors.lastname: Chern
authors.forename: G E
authors.initials: GE
authors.lastname: Fernandes
authors.forename: R K
authors.initials: RK
authors.lastname: Chang
authors.forename: Q
authors.initials: Q
authors.lastname: Song
authors.forename: L
authors.initials: L
authors.lastname: Xu
authors.forename: M
authors.initials: M
authors.lastname: Kneissl
authors.forename: N M
authors.initials: NM
authors.lastname: Johnson