US 12,014,246 B2
Nanophotonic quantum memory
Mihir Keshav Bhaskar, Cambridge, MA (US); Denis D. Sukachev, Cambridge, MA (US); Christian Thieu Nguyen, Cambridge, MA (US); Bartholomeus Machielse, Cambridge, MA (US); David S. Levonian, Cambridge, MA (US); Ralf Riedinger, Cambridge, MA (US); Mikhail D. Lukin, Cambridge, MA (US); and Marko Loncar, Cambridge, MA (US)
Assigned to President and Fellows of Harvard College, Cambridge, MA (US)
Appl. No. 17/623,757
Filed by President and Fellows of Harvard College, Cambridge, MA (US)
PCT Filed Jul. 16, 2020, PCT No. PCT/US2020/042316
§ 371(c)(1), (2) Date Dec. 29, 2021,
PCT Pub. No. WO2021/011765, PCT Pub. Date Jan. 21, 2021.
Claims priority of provisional application 62/875,340, filed on Jul. 17, 2019.
Prior Publication US 2022/0269974 A1, Aug. 25, 2022
Int. Cl. G06N 10/70 (2022.01); B82Y 20/00 (2011.01); G02B 6/122 (2006.01)
CPC G06N 10/70 (2022.01) [B82Y 20/00 (2013.01); G02B 6/1225 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method of making a quantum network node comprising:
calculating a plurality of scoring function F values for an array of at least two photonic crystal cavity unit cells, each photonic crystal cavity unit cell having a lattice constant α and a hole having a length Hx and a width Hy, wherein the scoring function comprises:
F=min(Q,Qcutoff)/(Qcutoff×Vmode)
wherein Q is a cavity quality factor, Qcutoff is an estimated maximum realizable Q, and Vmode is a cavity mode volume;
selecting a value of α, a value of Hx, and a value of Hy for which the scoring function value meets a scoring function value criteria;
forming, on a substrate, a waveguide region and the array of at least two photonic crystal cavity unit cells based on the selected value a, the selected value Hz, and the selected value Hy;
implanting at least one ion between a hole of a first photonic crystal cavity unit cell and a second photonic crystal cavity unit cell;
annealing the at least one implanted ion into at least one quantum defect; and
forming a coplanar microwave waveguide on the substrate configured to be electromagnetically coupled to the array of at least two photonic crystal cavity unit cells.