2013/08/02 by Christopher G. Poulton, Ravi Pant, Benjamin J. Eggleton · 2 citations
Engineering · Physics and Astronomy · #Acoustic wave #Acoustics #Advanced Fiber Optic Sensors #Brillouin scattering #Cladding (metalworking) #Core (optical fiber) #Coupling (piping) #Materials science #Mechanical and Optical Resonators #Optical fiber #Optics #Photonic and Optical Devices #Physical acoustics #Physics #Scattering #physics.optics
paper · pdf · doi:10.1364/josab.30.002657
arxiv created 2013/08/02 · openalex publication_date 2013/09/11 · arxiv updated 2015/06/16 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We examine the effect of acoustic mode confinement on stimulated Brillouin scattering (SBS) in optical waveguides that consist of a guiding core embedded in a solid substrate. We find that SBS can arise due to coupling to acoustic modes in three different regimes. First, the acoustic modes may be guided by total internal reflection; in this case, the SBS gain depends directly on the degree of confinement of the acoustic mode in the core, which is in turn determined by the acoustic V parameter. Second, the acoustic modes may be leaky but may nevertheless have a sufficiently long lifetime to have a large effect on the SBS gain; the lifetime of acoustic modes in this regime depends not only on the contrast in acoustic properties between the core and the cladding but is also highly dependent on the waveguide dimensions. Finally, SBS may occur due to coupling to free modes, which exist even in the absence of acoustic confinement; we find that the cumulative effect of coupling to these nonconfined modes results in significant SBS gain. We show how the different acoustic properties of core and cladding lead to these different regimes and discuss the feasibility of SBS experiments using different material systems.