US 12,253,357 B2
Interferometric measurement system using time-correlated photons
Gary Vacon, East Falmouth, MA (US); and Kristin A. Rauschenbach, Franconia, NH (US)
Assigned to Qubit Moving and Storage, LLC, Franconia, NH (US)
Filed by Qubit Moving and Storage, LLC, Franconia, NH (US)
Filed on Mar. 9, 2024, as Appl. No. 18/600,690.
Application 18/600,690 is a continuation of application No. 17/749,079, filed on May 19, 2022, granted, now 11,933,608.
Prior Publication US 2024/0263936 A1, Aug. 8, 2024
Int. Cl. G01B 9/02001 (2022.01)
CPC G01B 9/02007 (2013.01) [G01B 2290/55 (2013.01)] 23 Claims
OG exemplary drawing
 
1. An interferometric measurement system:
a) an optical source configured to simultaneously generate a set of four time-correlated photons such that a first pair of photons in the set of four time-correlated photons are time correlated indicating that a second pair of photons in the set of four time-correlated photons are time correlated and such that a photon from the first pair of photons emerges at a first output, another photon from the first pair of photons emerges at a second output, a photon from the second pair of photons emerges at a third output and another photon from the second pair of photons emerges at a fourth output;
b) an interferometer having a first input optically coupled to the first output of the optical source and configured to receive the photon from the first pair of photons and a second input optically coupled to the second output of the optical source and configured to receive the other photon from the first pair of photons and having a first output and a second output;
c) a first detector optically coupled to the first output of the interferometer and configured to generate an electrical signal in response to measurement of a photon;
d) a second detector optically coupled to the second output of the interferometer configured to generate an electrical signal in response to measurement of a photon;
e) a third detector optically coupled to the third output of the optical source and configured to generate an electrical signal in response to measurement of the photon from the second pair of photons;
f) a fourth detector optically coupled to the fourth output of the optical source and configured to generate an electrical signal in response to measurement of the other photon from the second pair of photons; and
g) a processor coupled to outputs of the first, second, third and fourth detector and configured to determine a coincidence of the generated electrical signal in response to measurement of the photon from the second pair of photons and the generated electrical signal in response to measurement of the other photon from the second pair of photons, thereby identifying the set of four time-correlated photons and heralding an interferometric measurement from the generated electrical signals of the first and second detectors.