Nitride-based photodiode at 510-nm wavelength for plastic optical fiber communication

We demonstrate a GaN-based waveguide photodiode at a wavelength of around 510 nm for plastic optical fiber communication. Compared with the performance of an Si-based photodiode in the same wavelength regime, our device can achieve better external efficiency. It also enjoys the unique advantage of monolithic integration with the GaN-based green-amber light-emitting-diode (LED). Our demonstrated photodiode exhibits high external efficiency (73%) and a 600-MHz electrical bandwidth. Under forward bias, this device can also serve as a transmitter (LED), and the measured optical center wavelength is around 515 nm with a 70-MHz electrical bandwidth.