title: Interaction-induced mode switching in steady-state microlasers.
abstract: We demonstrate that due to strong modal interactions through cross-gain saturation, the onset of a new lasing mode can switch off an existing mode via a negative power slope. In this process of interaction-induced mode switching (IMS) the two involved modes maintain their identities, i.e. they do not change their spatial field patterns or lasing frequencies. For a fixed pump profile, a simple analytic criterion for the occurrence of IMS is given in terms of their self- and cross-interaction coefficients and non-interacting thresholds, which is verified for the example of a two-dimensional microdisk laser. When the spatial pump profile is varied as the pump power is increased, IMS can be induced even when it would not occur with a fixed pump profile, as we show for two coupled laser cavities. Our findings apply to steady-state lasing and are hence different from dynamical mode switching or hopping. IMS may have potential applications in robust and flexible all-optical switching.
authors.forename: Li
authors.initials: L
authors.lastname: Ge
authors.forename: David
authors.initials: D
authors.lastname: Liu
authors.forename: Alexander
authors.initials: A
authors.lastname: Cerjan
authors.forename: Stefan
authors.initials: S
authors.lastname: Rotter
authors.forename: Hui
authors.initials: H
authors.lastname: Cao
authors.forename: Steven G
authors.initials: SG
authors.lastname: Johnson
authors.forename: Hakan E
authors.initials: HE
authors.lastname: Türeci
authors.forename: A Douglas
authors.initials: AD
authors.lastname: Stone