Search

Quantum well (QW) diodes have the capability to function as a light-emitting diode or a photodiode and inherently feature a partial emission-detection spectral overlap. Therefore, QW diode can sense light emission from another diode sharing the same QW active region. In association with distributed Bragg reflection (DBR) technique, we here present a wavelength-division multiplexing (WDM) visible light communication (VLC) over a single channel by using vertical assembly of red, green, and blue (RGB) QW diodes. The identical QW diodes separately functioning as a transmitter and a receiver establish a wireless communications link. The DBRs enable the transmission of longer-wavelength photons or the reflection of shorter-wavelength photons, creating an optical bandpass filter in conjunction with emission-detection spectral overlap, effectively boosting the capacity of an initially single communication channel. Both the transmitter and the receiver can be switched freely by software, forming time-division multiplexing (TDM) wireless light communication system using single optical path. We unite TDM and WDM together to demonstrate real-time TDM multichannel bidirectional communication using the vertical integration of RGB QW diodes, offering the great potential to establish TDM-WDM VLC. [ABSTRACT FROM AUTHOR]

Emerging deep-ultraviolet (DUV) light communication with attractive features fulfills the increasing demand for novel wireless communication without electromagnetic interference or solar noise influence. Here, we propose, manufacture, and characterize a solar-blind full-duplex light communication system using 275-nm DUV light-emitting diodes (LEDs). Four DUV LEDs connected in series form a unit, and the transmitter consists of an array of three independent units, which can be synchronously controlled using a main processing unit to modulate the emitted light. A solar-blind filter is inserted in front of the receiver due to the lack of an ultraviolet photodetector. Both the transmitter and receiver are encapsulated together to manufacture a full-duplex DUV light communication system, which can independently transmit and receive data with a maximal communication distance of 7 m at the same time. All users within a 46 m2 area of the system have access to the DUV communication network through an integrated wireless module. Real-time video is demonstrated and different types of files could be shared. Based on Transmission Control Protocol/Internet Protocol (TCP/IP), the system is finally performed in sunlight with a transmission rate of 10 Mbps and a packet loss rate of 1.28%. [ABSTRACT FROM AUTHOR]

GaN-based devices have grown rapidly in recent decades, due to their important research value and application prospects. There is a desire to monolithically integrate different GaN devices into a single chip for the development of future optoelectronic systems with low power consumption. In addition to improved multifunctional performance, a miniature integrated system can result in a significant reduction in material costs, processing costs, and packaging costs. In view of such prospects, we propose monolithic, top-down approaches to build III-nitride transmitter, modulator, waveguide, beam splitter, receiver, and monitor as a single unit onto a conventional GaN-on-silicon wafer without involving regrowth or postgrowth doping. Data communication among these components is realized through light propagation, opening up horizons for GaN optoelectronic systems on a chip. [ABSTRACT FROM AUTHOR]

Visible light communication (VLC) is a key technology for 6G. Here, we propose, fabricate, and characterize a vertical-structure light-emitting diode (VSLED) to manage the dilemma of both power and speed for VLCs. Ultrathin VSLED architecture offers the unique features of decreasing the RC time constant for increasing modulation bandwidth and reducing confined optical modes inside the diode for enhancing light extraction. A 580-nm-thick VSLED with a dominant emission wavelength of 427.8 nm is implemented on a 2-in. metal-based bonded III-nitride-on-silicon wafer. Based on a bit-loading discrete multitone modulation scheme, we establish a visible light communication system using 1 × 1 mm2 VSLED, which can achieve a data transmission rate of 608 Mbps at a baud rate of 200 MBaud. [ABSTRACT FROM AUTHOR]