US 12,306,040 B2
Superconducting single photon detector with photon number resolution
Mohsen Keshavarz Akhlaghi, North Vancouver (CA)
Assigned to PHOTONIC INC., Coquitlam (CA)
Appl. No. 18/573,369
Filed by PHOTONIC INC., Coquitlam (CA)
PCT Filed Jul. 22, 2022, PCT No. PCT/CA2022/051136
§ 371(c)(1), (2) Date Dec. 21, 2023,
PCT Pub. No. WO2023/000106, PCT Pub. Date Jan. 26, 2023.
Claims priority of provisional application 63/203,478, filed on Jul. 23, 2021.
Prior Publication US 2024/0361181 A1, Oct. 31, 2024
Int. Cl. G01J 1/44 (2006.01); G01J 1/02 (2006.01); G01J 1/04 (2006.01); G01R 19/00 (2006.01)
CPC G01J 1/44 (2013.01) [G01J 1/0252 (2013.01); G01J 1/0425 (2013.01); G01R 19/0092 (2013.01); G01J 2001/442 (2013.01)] 21 Claims
OG exemplary drawing
 
1. A photon number resolving detector (PNRD) comprising:
a waveguide having an optical input connected to receive photons for detection;
multiple nanowires extending transversely across the waveguide at spaced apart locations, each of the nanowires comprising a material that is superconducting at an operating temperature of the PNRD, each of the nanowires connected in series with an electrically resistive component to provide a branch, the branches electrically connected in parallel with one another;
wherein the PNRD is connectable to:
a power source to apply a voltage across the branches, and;
a current monitor to monitor an electrical current drawn from the power source by the branches;
and wherein, at the operating temperature, an electrical time constant of the nanowire is small enough to cause latching to a latched state when the nanowire absorbs a photon.