The enhancement of the reliability of the silicon-based III–V quantum well lasers, especially of those on an on-axis Si (001) substrate, is of great importance now a days for the development of Si-based photonic and even optoelectronic integrated circuits and is really quite challenging. As an experimental advancement, mainly by inserting a pair of InAlAs strained layers separately into the upper and lower AlGaAs cladding layers to effectively prevent the formation of the in-plane gliding misfit-dislocations within the boundary planes of the active region, the longest room-temperature and continuous-wave lifetime of the InGaAs/AlGaAs quantum well lasers on an on-axis Si (001) substrate with a cavity length of 1500 µm and a ridge width of 20 µm has been prolonged from a very initial record of ∼90 s to the present length longer than 31 min. While, the highest continuous-wave operation temperature of another one with a cavity length of 1000 µm and a ridge width of 10 µm has been shown as 103 °C with an extracted characteristic temperature of 152.7 K, further enhancement of the device reliability is still expected and would mainly depend on the level of the threading-dislocation-density reduction in the GaAs/Si virtual substrate.
Dual-mode photodetectors (DmPDs) have attracted considerable interest due to their ability to integrate multiple functionalities into a single device. However, 2D material/InP heterostructures, which exhibit built-in electric fields and rapid response characteristics, have not yet been utilized in DmPDs. In this work, we fabricate a high-performance DmPD based on a graphene/InP Van der Waals heterostructure in a facile way, achieving a broadband response from ultraviolet-visible to near-infrared wavelengths. The device incorporates two top electrodes contacting monolayer chemical vapor deposition (CVD) graphene and a bottom electrode on the backside of an InP substrate. By flexibly switching among these three electrodes, the as-fabricated DmPD can operate in a self-powered photovoltaic mode for energy-efficient high-speed imaging or in a biased photoconductive mode for detecting weak light signals, fully demonstrating its multifunctional detection capabilities. Specifically, in the self-powered photovoltaic mode, the DmPD leverages the vertically configured Schottky junction to achieve an on/off ratio of 8 × 103, a responsivity of 49.2 mA/W, a detectivity of 4.09 × 1011 Jones, and an ultrafast response, with a rising time (τr) and falling time (τf) of 2.8/6.2 μs. In the photoconductive mode at a 1 V bias, the photogating effect enhances the responsivity to 162.5 A/W. This work advances the development of InP-based multifunctional optoelectronic devices.
Silicon-based microcavity quantum dot lasers are attractive candidates for on-chip light sources in photonic integrated circuits due to their small size, low power consumption, and compatibility with silicon photonic platforms. However, integrating components like quantum dot lasers and photodetectors on a single chip remains challenging due to material compatibility issues and mode field mismatch problems. In this work, we have demonstrated monolithic integration of an InAs quantum dot microdisk light emitter, waveguide, and photodetector on a silicon platform using a shared epitaxial structure. The photodetector successfully monitored variations in light emitter output power, experimentally proving the feasibility of this integrated scheme. This work represents a key step toward multifunctional integrated photonic systems. Future efforts will focus on enhancing the light emitter output power, improving waveguide efficiency, and scaling up the integration density for advanced applications in optical communication.
The development of multifunctional optoelectronic logic gates (OELGs) with bipolar optical responses controlled by parameters such as wavelength, gate voltage, polarization, and light intensity has emerged as a key research direction in optical computing. Among these approaches, single-wavelength light-intensity modulation offers distinct advantages by enabling logic reconfiguration without additional electronic components or complex optical configurations. In this work, we integrate seven fundamental OELGs—AND, OR, NOT, NAND, NOR, XNOR, and XOR—into a single photoconductive photodetector based on a band-engineered graphene/InP heterostructure under 850 nm laser irradiation . The work-function mismatch between graphene and InP establishes a built-in electric field that directs photogenerated carrier flow across the heterointerface. As the incident light intensity increases, photogenerated carriers progressively shift the Fermi level in graphene, inducing a transition of the dominant charge carriers from holes to electrons. This light-intensity-dependent bipolar optical response enables reconfigurable logic functions. The as-fabricated device operates at an ultralow bias of 0.1 V and maintains stable logic performance across the visible-to-near-infrared (Vis–NIR) spectral range. This work presents a compact and scalable strategy for implementing all-in-one OELGs, which significantly reduces transistor count compared with conventional electronic logic devices, offering a promising route toward low-power, highly integrated optical computing chips.