By Topic

Theory and Design of THz Intracavity Gain-Flattened Filters for Monolithically Integrated Mode-Locked Lasers

Sign In

Cookies must be enabled to login.After enabling cookies , please use refresh or reload or ctrl+f5 on the browser for the login options.

Formats Non-Member Member
$31 $13
Learn how you can qualify for the best price for this item!
Become an IEEE Member or Subscribe to
IEEE Xplore for exclusive pricing!
close button

puzzle piece

IEEE membership options for an individual and IEEE Xplore subscriptions for an organization offer the most affordable access to essential journal articles, conference papers, standards, eBooks, and eLearning courses.

Learn more about:

IEEE membership

IEEE Xplore subscriptions

6 Author(s)
Parker, J.S. ; Dept. of Electr. Eng., Univ. of California, Santa Barbara, CA, USA ; Guzzon, R.S. ; Norberg, E.J. ; Bhardwaj, A.
more authors

We present the theory and design of a tunable gain-flattening filter for integrated mode-locked lasers (MLLs). The filter provides the inverse of the semiconductor spectral gain profile and produces a broad flattened net gain. This improves the performance of MLLs by allowing more modes to lase simultaneously. We demonstrate a gain-flattened MLL with a record 10 dB bandwidth of 2.08 THz, the widest frequency comb span for an integrated quantum-well-based laser at 1.55 μm. Gain-flattening theory is used to extend the integrated comb span to 40 nm. We use scattering matrices to investigate feed-forward filters based on asymmetric Mach-Zehnder interferometers (MZIs). We compare MZI filters designed for a fixed coupling value to those that use an active gain arm to adjust the extinction ratio. Tunable zero placement of these filters is achieved using a passive phase tuning arm. The optimized gain-flattening filter has a 5 dB extinction ratio and a 70 nm free-spectral-range. When the filter is incorporated into a ring MLL, simulations predict a 40 nm, i.e., 5 THz, comb span with a power variation <; 3.5 dB.

Published in:

Quantum Electronics, IEEE Journal of  (Volume:48 ,  Issue: 2 )