title: Spin-cavity interactions between a quantum dot molecule and a photonic crystal cavity.
abstract: The integration of InAs/GaAs quantum dots into nanophotonic cavities has led to impressive demonstrations of cavity quantum electrodynamics. However, these demonstrations are primarily based on two-level excitonic systems. Efforts to couple long-lived quantum dot electron spin states with a cavity are only now succeeding. Here we report a two-spin-cavity system, achieved by embedding an InAs quantum dot molecule within a photonic crystal cavity. With this system we obtain a spin singlet-triplet Λ-system where the ground-state spin splitting exceeds the cavity linewidth by an order of magnitude. This allows us to observe cavity-stimulated Raman emission that is highly spin-selective. Moreover, we demonstrate the first cases of cavity-enhanced optical nonlinearities in a solid-state Λ-system. This provides an all-optical, local method to control the spin exchange splitting. Incorporation of a highly engineerable quantum dot molecule into the photonic crystal architecture advances prospects for a quantum network.
authors.affiliation: NRC research associate residing at the Naval Research Laboratory, Washington, District of Columbia 20375, USA.
authors.forename: Patrick M
authors.initials: PM
authors.lastname: Vora
authors.affiliation: Naval Research Laboratory, Washington, District of Columbia 20375, USA.
authors.forename: Allan S
authors.initials: AS
authors.lastname: Bracker
authors.affiliation: Naval Research Laboratory, Washington, District of Columbia 20375, USA.
authors.forename: Samuel G
authors.initials: SG
authors.lastname: Carter
authors.affiliation: NRC research associate residing at the Naval Research Laboratory, Washington, District of Columbia 20375, USA.
authors.forename: Timothy M
authors.initials: TM
authors.lastname: Sweeney
authors.affiliation: Sotera Defense Solutions Inc., Columbia, Maryland 21046, USA.
authors.forename: Mijin
authors.initials: M
authors.lastname: Kim
authors.affiliation: Naval Research Laboratory, Washington, District of Columbia 20375, USA.
authors.forename: Chul Soo
authors.initials: CS
authors.lastname: Kim
authors.affiliation: NRC research associate residing at the Naval Research Laboratory, Washington, District of Columbia 20375, USA.
authors.forename: Lily
authors.initials: L
authors.lastname: Yang
authors.affiliation: US Naval Academy, Annapolis, Maryland 21402, USA.
authors.forename: Peter G
authors.initials: PG
authors.lastname: Brereton
authors.affiliation: Naval Research Laboratory, Washington, District of Columbia 20375, USA.
authors.forename: Sophia E
authors.initials: SE
authors.lastname: Economou
authors.affiliation: Naval Research Laboratory, Washington, District of Columbia 20375, USA.
authors.forename: Daniel
authors.initials: D
authors.lastname: Gammon