Broadband excess intensity noise due to an asymmetric Brillouin gain spectrum in optical fibers (Conference Presentation)

Sven Hochheim; Jörg Neumann; Dietmar Kracht; Michael Steinke

doi:10.1117/12.2508313

13 March 2019 Broadband excess intensity noise due to an asymmetric Brillouin gain spectrum in optical fibers (Conference Presentation)

Sven Hochheim, Jörg Neumann, Dietmar Kracht, Michael Steinke

Author Affiliations +

Proceedings Volume 10897, Fiber Lasers XVI: Technology and Systems; 108971R (2019) https://doi.org/10.1117/12.2508313
Event: SPIE LASE, 2019, San Francisco, California, United States

Abstract

Fiber-based single-frequency amplifiers, e.g. for gravitational wave detectors, are typically limited by the nonlinear effect of the stimulated Brillouin scattering (SBS). In addition to a decreasing output power level, SBS also initiates a broadband intensity noise in a frequency regime up to several MHz. Several published theories provide models to explain this excess intensity noise. Here, we report new theoretical and experimental studies, which suggest the conversion from phase to intensity noise by an asymmetric Brillouin gain spectrum. Due to the asymmetric Brillouin gain profile, upper and lower frequency sidebands experience a frequency-dependent gain-factor and a differential non-zero phase shift. Thus, the sidebands do not cancel each other out and the differential non-zero phase shifts provides an additional contribution to the intensity noise. Using a measured asymmetric Brillouin gain spectrum and the 1/f-frequency noise characteristics of the pump source, we are able to reconstruct the shape of the excess intensity noise fairly well. In addition, further evidence for an asymmetric SBS gain profile has been observed. Due to small back reflections at the fiber end faces corresponding resonances are evident in the intensity noise spectrum. Through the asymmetry of the SBS gain profile and the differential non-zero phase shift, the conditions for the resonator eigenfrequencies are influenced. Therefore, the beat frequency between the upper and lower eigenfrequencies with the carrier are not equal anymore, which becomes noticeable in a splitting of resonances in the intensity noise spectrum.

Conference Presentation

Citation Download Citation

Sven Hochheim, Jörg Neumann, Dietmar Kracht, and Michael Steinke "Broadband excess intensity noise due to an asymmetric Brillouin gain spectrum in optical fibers (Conference Presentation)", Proc. SPIE 10897, Fiber Lasers XVI: Technology and Systems, 108971R (13 March 2019); https://doi.org/10.1117/12.2508313

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available

Members: $17.00

Non-members: $21.00 ADD TO CART

PROCEEDINGS
PRESENTATION

WATCH
PRESENTATION SAVE TO MY LIBRARY

GET CITATION

KEYWORDS

Optical fibers

Phase shifts

Fiber amplifiers

Optical amplifiers

Resonators

Scattering

Sensors

Keywords/Phrases

Search In:

Publication Years