This paper investigated the use of semipolar InGaN/GaN multiple quantum well based micro-photodetectors (μPDs) as the optical receiver for visible light communication (VLC). The fabricated semipolar μPDs exhibited a low dark current of 1.6 pA at −10 V, a responsivity of 0.191 A W−1, and a −3 dB modulation bandwidth of 347 MHz. A high data rate of up to 1.55 Gbit s−1 was achievable by utilizing the extended bandwidth of more than −10 dB, and based on a straight-forward non-return-to-zero on–off keying modulation scheme. This development demonstrated the feasibility of wavelength-selective detection scheme using semipolar μPD for high-data-capacity VLC systems.

Visible light communication (VLC) has drawn significant attention in recent years. Though high-speed visiblelight sources have seen significant advances, commercially available photodetectors have low wavelength selectivity and modulation bandwidth in the near-violet-blue wavelengths, making them a bottleneck in VLC links. Here we show a record 7.4-Gbit/s visible-light communication link using a wavelengthselective, (2021)-oriented, semipolar InGaN/GaN multiplequantum-well micro-photodetector (µPD) on GaN substrate. This is achieved by leveraging on the unique photodetection properties of semipolar µPDs, combined with an optimized communication system utilizing bit-and power-loading schemes in orthogonal frequency-division multiplexing (OFDM) modulation over a 2-GHz bandwidth. We used a 405-nm violet laser diode transmitter as the responsivity of the µPD was highest within the responsivity range of 360-420 nm. The investigation fully demonstrated the feasibility and favorable choice of semipolar InGaN/GaN µPDs for multi-Gbit/s optical wireless communication.

We report on wavelength-selective semipolar (2021) InGaN/GaN micro-photodetector with broad modulation bandwidth of 293.52 MHz, outperforming polar-based devices. A 1.5-Gbit/s data rate was achieved without the need of spectral-efficient modulation format.

No abstract