A phase sensitive photodiode is fabricated on a thin (380 nm) silicon layer with a subwavelength (670 nm period) grating. Optical absorption of the photodiode is enhanced by guided resonance of the grating to approximately 81% at the incident angle of 34.6° under TE polarization. Utilizing light beams impinging at the angles with enhanced sensitivities, a phase of two beams interfering in the silicon layer is precisely detected. The compact structure of the proposed detector can be used in several microinterferometers and integrated optics.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)