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Title: On-chip spin-orbit locking of quantum emitters in 2D materials for chiral emission

Light carries both spin angular momentum (SAM) and orbital angular momentum (OAM), which can be used as potential degrees of freedom for quantum information processing. Quantum emitters are ideal candidates towards on-chip control and manipulation of the full SAM–OAM state space. Here, we show coupling of a spin-polarized quantum emitter in a monolayerWSe2with the whispering gallery mode of aSi3N4ring resonator. The cavity mode carries a transverse SAM ofσ<#comment/>=±<#comment/>1in the evanescent regions, with the sign depending on the orbital power flow direction of the light. By tailoring the cavity–emitter interaction, we couple the intrinsic spin state of the quantum emitter to the SAM and propagation direction of the cavity mode, which leads to spin–orbit locking and subsequent chiral single-photon emission. Furthermore, by engineering how light is scattered from the WGM, we create a high-order Bessel beam which opens up the possibility to generate optical vortex carrying OAM states.

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Award ID(s):
1932803 1842612
Publication Date:
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Article No. 953
Optical Society of America
Sponsoring Org:
National Science Foundation
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