Title :
Phase coherence of optical waveguides
Author :
Adar, R. ; Henry, C.H. ; Milbrodt, M.A. ; Kistler, R.C.
Author_Institution :
AT&T Bell Labs., Murray Hill, NJ, USA
fDate :
4/1/1994 12:00:00 AM
Abstract :
The effective refractive index of real waveguides is not constant, but fluctuates as a result of variations in composition and waveguide dimensions. Consequently, the accumulated phase during propagation has a component that undergoes a random walk and whose mean square increases with length ⟨Δφ2⟩=2L/Lcoh. These phase fluctuations result in wavelength fluctuations in Mach-Zehnder interferometers, especially in interferometers of low order. By measuring these fluctuations for Mach-Zehnder interferometers of different order, we have verified the above relation and determined that Lcoh≈27 m for our phosphorus-doped core silica on silicon waveguides
Keywords :
elemental semiconductors; light coherence; light interferometers; optical waveguide theory; phosphorus; refractive index; silicon; silicon compounds; Mach-Zehnder interferometer; Si; Si waveguides; SiO2:P; accumulated phase; composition; effective refractive index; length; mean square; optical waveguides; phase coherence; phase fluctuations; propagation; random walk; waveguide dimensions; wavelength fluctuations; Coherence; Fluctuations; Mach-Zehnder interferometers; Optical interferometry; Optical propagation; Optical refraction; Optical variables control; Optical waveguides; Refractive index; Wavelength measurement;
Journal_Title :
Lightwave Technology, Journal of
