Abstract
Optical frequency combs have resulted in significant advances in optical frequency metrology and found wide applications in precise physical measurements and molecular fingerprinting. A direct analogue of frequency combs in the phononic or acoustic domain has not been reported to date. In this Letter, we report the first clear experimental evidence for a phononic frequency comb. We show that the phononic frequency comb is generated through the intrinsic coupling of a driven phonon mode with an autoparametrically excited subharmonic mode. The experiments depict the comb generation process evidenced by a spectral response consisting of equally spaced discrete and phase coherent comb lines. Through systematic experiments at different drive frequencies and amplitudes, we portray the well-connected process of phononic frequency comb formation and define the attributes to control the features associated with comb formation in such a system. In addition to the demonstration of frequency comb, the interplay between the nonlinear resonances and the well-known Duffing phenomenon is also observed.
- Received 3 October 2016
DOI:https://doi.org/10.1103/PhysRevLett.118.033903
© 2017 American Physical Society
Physics Subject Headings (PhySH)
Focus
Celebrated Optical Trick Goes Vibrational
Published 17 January 2017
A micromechanical device generates a series of precise, equally spaced vibration frequencies, analogous to the light of the “optical frequency comb,” which has dramatically improved precision measurements.
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