	US 11,860,420 B2
	Microgear photonic crystal patterning for chip-integrated optical ring resonators
Kartik Srinivasan, Rockville, MD (US); and Xiyuan Lu, Montgomery Village, MD (US)
Assigned to University of Maryland, College Park, College Park, MD (US); and Government of the United States of America, as Represented by the Secretary of Commerce, Gaithersburg, MD (US)
Filed by University of Maryland, College Park, College Park, MD (US); and Government of the United States of America, as Represented by the Secretary of Commerce, Gaithersburg, MD (US)
Filed on Feb. 17, 2022, as Appl. No. 17/674,079.
Claims priority of provisional application 63/150,637, filed on Feb. 18, 2021.
Prior Publication US 2022/0260782 A1, Aug. 18, 2022
Int. Cl. G02B 6/12 (2006.01); G02B 6/122 (2006.01); G02B 6/293 (2006.01); B82Y 20/00 (2011.01)

CPC G02B 6/29341 (2013.01) [G02B 6/122 (2013.01); G02B 6/12007 (2013.01); G02B 6/29338 (2013.01); B82Y 20/00 (2013.01); G02F 2203/15 (2013.01)]

28 Claims

1. An optical cavity, comprising:

a ring defining an internal boundary and an external boundary, at least one of the internal boundary or the external boundary being periodically modulated to define a gear-shaped configuration including a plurality of teeth, thereby enabling a plurality of slow-light modes wherein at least one slow-light mode of the plurality of slow-light modes has an optical quality factor (Q) of at least about 1.1×10⁶and a group velocity slowdown ratio (SR) of at least about 10; and

at least one waveguide coupled to the ring.