US 12,276,710 B2
Quantum spin amplification
Aashish Clerk, Chicago, IL (US); Martin Koppenhöfer, Chicago, IL (US); and Peter Groszkowski, Knoxville, TN (US)
Assigned to The University of Chicago, Chicago, IL (US)
Filed by The University of Chicago, Chicago, IL (US)
Filed on Nov. 22, 2022, as Appl. No. 18/057,807.
Claims priority of provisional application 63/264,617, filed on Nov. 29, 2021.
Prior Publication US 2023/0194634 A1, Jun. 22, 2023
Int. Cl. G01R 33/00 (2006.01); G01R 33/12 (2006.01)
CPC G01R 33/0029 (2013.01) [G01R 33/1284 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method for quantum spin amplification, comprising:
spin-polarizing an ensemble of quantum spins in an initial spin state to generate a sensing spin state that is transversely polarized with respect to a quantization axis, the quantum spins identically having an upper energy state and a lower energy state;
accumulating, by the sensing spin state, a phase shift that transforms the sensing spin state into a phase-accumulated spin state having first and second transverse polarization components that are orthogonal to each other, the phase shift being based on an energy spacing between the upper and lower energy states;
transforming the phase-accumulated spin state into an intermediate spin state by rotating the first transverse polarization component into a longitudinal polarization component of the intermediate spin state;
coupling the ensemble of quantum spins to an auxiliary mode, wherein the intermediate spin state, in response to said coupling, evolves such that the second transverse polarization component is amplified into an amplified transverse polarization; and
measuring the amplified transverse polarization.