Narrow-band tunable optical filters based on cascaded Fabry-Perot cavities

Abstract

Narrow-band tunable optical filters (TOF) based on three cascaded Fabry-Perot (FP) cavities are demonstrated. The FP cavities are fabricated with Pb(Mg1/3Nb2/3)O3-PbTiO3 (PMN-PT), which is a transparent electro-optic ceramic. With a reflective design, the optical signal passes the three FP cavities twice. Thus we can design the FP cavities with a relatively low reflectivity, which enables it more tolerant to the loss in the cavities. Two types of TOF samples are fabricated. The specifications of the transmissive type TOF with dual-ports are tuning range >48nm, FWHM (full width half maximum) <0.06nm, insertion loss <3.87dB, crosstalk <−39dB, which meet the requirements by optical performance monitor (OPM) applications. The specifications of the reflective type TOF with single-port are tuning range >48nm, FWHM (full width half maximum) <0.1nm, insertion loss <2.82dB, crosstalk <−30dB, which can be employed in tunable fiber lasers for wavelength selection and tuning.

Polarization Insensitivity Research of the Three-layer Silicon-based Symmetric Cascade Optical Sensor

“…GMR is more likely to occur in subwavelength grating structures [6][7][8], where the grating period is significantly smaller than the incident light wavelength. Such structures exhibit high diffraction efficiency and narrow bandwidth properties, making them suitable for designing narrow-band filters [9][10][11][12][13], optical modulators [14][15][16][17][18], and sensors [19][20][21][22].…”