US 12,468,087 B2
Apparatus and methods for reduction of crosstalk in integrated photonics applied to addressing quantum memories
Michael L. Fanto, Rome, NY (US); David Hucul, Fayette, NY (US); Stefan Preble, Pittsford, NY (US); Amos M. Smith, Chittenango, NY (US); Zachary Smith, Clinton, NY (US); Kathy-Anne Soderberg, Manilus, NY (US); and Christopher Tison, Rome, NY (US)
Assigned to United States of America as represented by the Secretary of the Air Force, Rome, NY (US)
Filed by Government of the United States as represented by the Secretary of the Air Force, Rome, NY (US)
Filed on Mar. 28, 2023, as Appl. No. 18/191,013.
Prior Publication US 2024/0329303 A1, Oct. 3, 2024
Int. Cl. G02B 6/12 (2006.01); G02B 6/122 (2006.01); G02B 6/136 (2006.01)
CPC G02B 6/122 (2013.01) [G02B 6/136 (2013.01)] 18 Claims
OG exemplary drawing
 
1. An apparatus for the reduction of crosstalk in integrated photonic devices, comprising:
a photonic chip substrate having an input facet and an output facet;
at least one waveguide disposed in said chip, having its input coincident with said input facet and at least one output coincident with said output facet;
a plurality of scatter reduction features, comprising:
fill, disposed on either side of said waveguide to absorb and block photon propagation;
a first plurality of trenches etched in said substrate and disposed on either side of said waveguide so as to create an air gap along the sides of said waveguide that prevents scatter-induced sideways slab mode propagation of light;
bridges etched in said substrate and undercut beneath said waveguide so as to create an air gap beneath said waveguide so as to prevent scatter-induced underside slab mode propagation of light;
a second plurality of trenches etched in said substrate extending to said output facet so as to prevent the propagation of slab modes between said at least one waveguide output;
wherein said plurality of scatter reduction features further comprises:
a descending escalator disposed within a path of said waveguide directing light from a first upper SiN layer into a lower Si layer;
an ascending escalator disposed within a path of said waveguide directing light from said lower Si layer into a second upper SiN layer;
wherein said first upper and said second upper SiN layers overlap said lower Si layer; and
wherein said first upper SiN layer, said lower Si layer, and said second upper SiN layer, in combination, produce wavelength selective filtering of light.