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Title: Strong optomechanical interactions with long-lived fundamental acoustic waves

Traveling-wave optomechanical interactions, known as Brillouin interactions, have now been established as a powerful and versatile resource for photonic sources, sensors, and radio-frequency processors. However, established Brillouin-based interactions with sufficient interaction strengths involve short phonon lifetimes, which critically limit their performance for applications, including radio-frequency 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 single-sideband amplification. Using sensitive four-wave mixing spectroscopy controlling for noise and spatial mode coupling, optomechanical interactions with long><#comment/>2µ<#comment/>sphonon lifetimes and strong><#comment/>400W−<#comment/>1m−<#comment/>1coupling are observed in a tapered fiber. In addition, we demonstrate novel phonon self-interference effects resulting from the unique combination of an axially varying device geometry with long phonon lifetimes. A generalized theoretical model, in excellent agreement with experiments, is developed with broad applicability to inhomogeneous optomechanical systems.

 
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Award ID(s):
1943658
NSF-PAR ID:
10393241
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
Optical Society of America
Date Published:
Journal Name:
Optica
Volume:
10
Issue:
2
ISSN:
2334-2536
Page Range / eLocation ID:
Article No. 206
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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