The midIR spectroscopic properties of
Travelingwave optomechanical interactions, known as Brillouin interactions, have now been established as a powerful and versatile resource for photonic sources, sensors, and radiofrequency processors. However, established Brillouinbased interactions with sufficient interaction strengths involve short phonon lifetimes, which critically limit their performance for applications, including radiofrequency filtering and optomechanical storage devices. Here, we investigate a new paradigm of optomechanical interactions with tightly confined fundamental acoustic modes, which enables the unique and desirable combination of high optomechanical coupling, long phonon lifetimes, tunable phonon frequencies, and singlesideband amplification. Using sensitive fourwave mixing spectroscopy controlling for noise and spatial mode coupling, optomechanical interactions with long
 Award ID(s):
 1943658
 NSFPAR ID:
 10393241
 Publisher / Repository:
 Optical Society of America
 Date Published:
 Journal Name:
 Optica
 Volume:
 10
 Issue:
 2
 ISSN:
 23342536
 Page Range / eLocation ID:
 Article No. 206
 Format(s):
 Medium: X
 Sponsoring Org:
 National Science Foundation
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