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The time-programmable frequency comb and its use in quantum-limited ranging



Emily Caldwell, Laura Sinclair, Nathan R. Newbury, Jean-Daniel Deschenes


Two decades after its invention, the frequency comb is an unparalleled ruler for frequency, time, and distance metrology due to the rigid spacing of its optical output. Here, in contrast, we demonstrate a programable frequency comb by combining self-referenced stabilization with digital phase control. This source emits coherent pulses with programmable time and phase at ±2 attosecond accuracy, with respect to the underlying oscillator. Among other capabilities, it enables a tracking frequency comb for quantum-limited detection of weak signals in comb-based sensing without sacrificing accuracy. In dual-comb ranging, the SNR is improved 10,000-fold to enable ranging with precision as low as 0.7 nm, a 26-kHz measurement rate, and a nearly quantum-limited detection threshold of 0.013 mean signal photons per pulse. Beyond ranging, applications in time/frequency metrology, comb-based linear and nonlinear spectroscopy, pump-probe experiments, and compressive sensing should benefit from coherent control of the comb pulse time and phase.


Frequency Comb, Optical Metrology, Dual-comb Ranging, Optical Time Transfer


Caldwell, E. , Sinclair, L. , Newbury, N. and Deschenes, J. (2022), The time-programmable frequency comb and its use in quantum-limited ranging, Nature, [online], (Accessed April 20, 2024)
Created October 27, 2022, Updated March 20, 2023