Athermal operation of silicon waveguides: spectral, second order and footprint dependencies.
We report the design criteria and performance of Si ring resonators for passive athermal applications in wavelength division multiplexing (WDM). The waveguide design rules address i) positive-negative thermo-optic (TO) composite structures, ii) resonant wavelength dependent geometry to achieve constant confinement factor (Gamma), and iii) observation of small residual second order effects. We develop exact design requirements for a temperature dependent resonant wavelength shift (TDWS) of 0 pm/K and present prototype TDWS performance of 0.5 pm/K. We evaluate the materials selection tradeoffs between high-index contrast (HIC) and low-index contrast (LIC) systems and show, remarkably, that FSR and footprint become comparable under the constraint of athermal design.
Raghunathan
Vivek
V
Microphotonics Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA. vivekr@mit.edu
Ye
Winnie N
WN
Hu
Juejun
J
Izuhara
Tomoyuki
T
Michel
Jurgen
J
Kimerling
Lionel
L
D004581:Electronics / Q000295:instrumentation / Q000379:methods; D006358:Hot Temperature; D008962:Models, Theoretical; D055095:Optics and Photonics / Q000295:instrumentation* / Q000379:methods*; D011108:Polymers / Q000737:chemistry; D012031:Refractometry / Q000295:instrumentation / Q000379:methods; D012825:Silicon / Q000737:chemistry*; D017655:Silicon Compounds / Q000737:chemistry*
D011108:Polymers; D017655:Silicon Compounds; C032734:silicon nitride; D012825:Silicon