TUNABLE PHOTODETECTORS AND LIGHT-EMITTING-DIODES FOR WAVELENGTH-DIVISION MULTIPLEXING

The authors propose and analyse a hybrid device structure which extend s the dynamic tuning range of vertical-cavity photodiodes and emitters . The device consists of a conventional, epitaxial pin junction quantu m-well diode grown on a quarter-wave mirror stack. The upper mirror is attached to the underside of a micromachined membrane fabricated on t op of the epilayer. This configuration allows the upper mirror to be e lectrostatically deflected towards the episurface, reducing the overal l vertical cavity length which tunes the resonance wavelength over the entire free spectral range of the cavity. Simulations of the device i ndicate that eight-channel operation between 900 and 1000 nm can be ac hieved with low crosstalk. It is expected that this device will find u se in wavelength-division-multiplexing applications.