US 12,253,719 B2
Mach Zehnder lattice based generalized Mach Zehnder interferometer
Hugo Cable, San Mateo, CA (US)
Assigned to Psiquantum, Corp., Palo Alto, CA (US)
Filed by Psiquantum, Corp., Palo Alto, CA (US)
Filed on Jul. 6, 2022, as Appl. No. 17/858,852.
Claims priority of provisional application 63/218,651, filed on Jul. 6, 2021.
Prior Publication US 2023/0021995 A1, Jan. 26, 2023
Int. Cl. G02B 6/293 (2006.01); G02F 1/21 (2006.01); G02F 1/225 (2006.01)
CPC G02B 6/29355 (2013.01) [G02F 1/212 (2021.01); G02F 1/225 (2013.01)] 17 Claims
OG exemplary drawing
 
1. A circuit comprising:
a first Mach Zehnder lattice having a first waveguide defining a first input path and first output path, a second waveguide defining a second input path and a second output path, the first Mach Zehnder lattice including a plurality of first active phase shifters disposed along the first waveguide and a plurality of directional coupler regions disposed along both waveguides between the first active phase shifters;
a second Mach Zehnder lattice having a first waveguide defining a first input path and first output path, a second waveguide defining a second input path and a second output path, the second Mach Zehnder lattice including a plurality of second active phase shifters disposed along the second waveguide and a plurality of directional coupler regions disposed along both waveguides between the second active phase shifters;
a first passive phase shifter coupled between the first output path of the first Mach Zehnder lattice and the first input path of the second Mach Zehnder lattice, the first passive phase shifter implementing a first phase shift; and
a second passive phase shifter coupled between the second output path of the first Mach Zehnder lattice and the second input path of the second Mach Zehnder lattice, the second passive phase shifter implementing a second phase shift that differs from the first phase shift by π radians.