Integrating solid-state quantum emitters with photonic circuits
is essential for realizing large-scale quantum photonic processors. Negatively
charged tin-vacancy (SnV−) centers in diamond have emerged as promising
candidates for quantum emitters because of their excellent optical and spin
properties, including narrow-linewidth emission and long spin coherence times.
SnV− centers need to be incorporated in optical waveguides for efficient onchip
routing of the photons they generate. However, such integration has yet to
be realized. In this Letter, we demonstrate the coupling of SnV− centers to a
nanophotonic waveguide. We realize this device by leveraging our recently
developed shallow ion implantation and growth method for the generation of
high-quality SnV− centers and the advanced quasi-isotropic diamond
fabrication technique. We confirm the compatibility and robustness of these
techniques through successful coupling of narrow-linewidth SnV− centers (as
narrow as 36 ± 2 MHz) to the diamond waveguide. Furthermore, we investigate the stability of waveguide-coupled SnV− centers
under resonant excitation. Our results are an important step toward SnV−-based on-chip spin-photon interfaces, single-photon
nonlinearity, and photon-mediated spin interactions.
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High-density integrated delay line using extreme skin-depth subwavelength grating waveguides
Optical delay lines control the flow of light in time, introducing phase and group delays for engineering interferences and ultrashort pulses. Photonic integration of such optical delay lines is essential for chip-scale lightwave signal processing and pulse control. However, typical photonic delay lines based on long spiral waveguides require extensively large chip footprints, ranging from mm2to cm2scales. Here we present a scalable, high-density integrated delay line using a skin-depth engineered subwavelength grating waveguide, i.e., an extreme skin-depth (eskid) waveguide. The eskid waveguide suppresses the crosstalk between closely spaced waveguides, significantly saving the chip footprint area. Our eskid-based photonic delay line is easily scalable by increasing the number of turns and should improve the photonic chip integration density.
more » « less- Award ID(s):
- 1930784
- NSF-PAR ID:
- 10402692
- Publisher / Repository:
- Optical Society of America
- Date Published:
- Journal Name:
- Optics Letters
- Volume:
- 48
- Issue:
- 7
- ISSN:
- 0146-9592; OPLEDP
- Page Range / eLocation ID:
- Article No. 1662
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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