Patent ID: 11869679
Assignee: HRL LABORATORIES, LLC
Field: Measurement (Instruments)
Classification: CPC G  H | IPC G  H

Claim 20:
21. A method of creating a stable frequency reference, said method comprising:
(a) creating an atomic vapor;
(b) ionizing at least some atoms in said atomic vapor, to form ionized atoms;
(c) collimating said ionized atoms in an ion collimator, to form a collimated beam of said ionized atoms;
(d) optionally, illuminating some of said ionized atoms with a cooling laser;
(e) illuminating at least some of said ionized atoms with a first probe laser at a first-probe-laser frequency;
(f) illuminating at least some of said ionized atoms with a second probe laser at a second-probe-laser frequency;
(g) adjusting said first-probe-laser frequency and said second-probe-laser frequency using Ramsey spectroscopy to an S→D transition of at least some of said ionized atoms; and
(h) illuminating at least some of said ionized atoms with a readout laser to determine a ground-state population of said ionized atoms.