US 12,218,484 B2
Variable-width waveguide for semiconductor optical amplifier devices
Alexey Kovsh, Saratoga, CA (US); David Towne, San Carlos, CA (US); and Peter Parkinson, San Jose, CA (US)
Assigned to ARISTA NETWORKS, INC., Santa Clara, CA (US)
Filed by Arista Networks, Inc., Santa Clara, CA (US)
Filed on Apr. 2, 2021, as Appl. No. 17/221,644.
Prior Publication US 2022/0320826 A1, Oct. 6, 2022
Int. Cl. H01S 5/00 (2006.01); H01S 5/042 (2006.01); H01S 5/10 (2021.01); H01S 5/34 (2006.01); H01S 5/343 (2006.01); H04B 10/50 (2013.01)
CPC H01S 5/1003 (2013.01) [H01S 5/042 (2013.01); H01S 5/3412 (2013.01); H01S 5/343 (2013.01); H04B 10/503 (2013.01)] 19 Claims
OG exemplary drawing
 
1. A semiconductor optical amplifier, comprising:
a semiconductor-based gain medium configured to receive a drive current; and
a variable-width waveguide in the semiconductor-based gain medium, the variable-width waveguide including a plurality of narrow width regions and a plurality of wide width regions positioned alternately along a longitudinal axis of the waveguide, and including a plurality of transition regions having adiabatically varying widths, each transition region connecting adjacent ones of the plurality of narrow width and wide width regions and the waveguide having a reduced drive current density in the plurality of wide width regions relative to the drive current density in the plurality of narrow width regions,
wherein each of the transition regions has one of an adiabatically increasing width and an adiabatically decreasing width relative to a direction of propagation of an optical signal along the longitudinal axis through the variable-width waveguide.