We demonstrate the formation of a complex, multi-wavelength, three-dimensional laser beam configuration with integrated metasurface (MS) optics. Our experiments support the development of a compact Sr optical-lattice clock, which leverages magneto-optical trapping at 461 nm and 689 nm without bulk free-space optics. We integrate six mm-scale metasurfaces on a fused silica substrate and illuminate them with light from optical fibers. The metasurfaces provide full control of beam pointing, divergence, and polarization to create the laser configuration for a magneto-optical trap. We report the efficiency and integration of the visible laser beam configuration, demonstrating the suitability of metasurface optics for atomic laser cooling.
Integrating planar photonics for multi-beam generation and atomic clock packaging on chip
Abstract The commercialization of atomic technologies requires replacing laboratory-scale laser setups with compact and manufacturable optical platforms. Complex arrangements of free-space beams can be generated on chip through a combination of integrated photonics and metasurface optics. In this work, we combine these two technologies using flip-chip bonding and demonstrate an integrated optical architecture for realizing a compact strontium atomic clock. Our planar design includes twelve beams in two co-aligned magneto-optical traps. These beams are directed above the chip to intersect at a central location with diameters as large as 1 cm. Our design also includes two co-propagating beams at lattice and clock wavelengths. These beams emit collinearly and vertically to probe the center of the magneto-optical trap, where they will have diameters of ≈100 µm. With these devices we demonstrate that our integrated photonic platform is scalable to an arbitrary number of beams, each with different wavelengths, geometries, and polarizations.
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- Award ID(s):
- 2016244
- PAR ID:
- 10431138
- Date Published:
- Journal Name:
- Light: Science & Applications
- Volume:
- 12
- Issue:
- 1
- ISSN:
- 2047-7538
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract Realization of chip‐scale nonreciprocal optics such as isolators and circulators is highly demanding for all‐optical signal routing and protection with standard photonics foundry process. Owing to the significant challenge for incorporating magneto‐optical materials on chip, the exploration of magnetic‐free alternatives has become exceedingly imperative in integrated photonics. Here, a chip‐based, tunable all‐optical isolator at the telecommunication band is demonstrated, which is based upon bulk stimulated Brillouin scattering (SBS) in a high‐Q silica microtoroid resonator. This device exhibits remarkable characteristics over most state‐of‐the‐art implements, including high isolation ratio, no insertion loss, and large working power range. Thanks to the guided acoustic wave and accompanying momentum‐conservation condition, bulk SBS also assist in realizing the nonreciprocal parity‐time symmetry in two directly coupled microresonators. The breach of time‐reversal symmetry further makes the design a versatile arena for developing many formidable ultra‐compact devices such as unidirectional single‐mode Brillouin lasers and supersensitive photonic sensors.
- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1038/s41377-023-01081-x
