Silicon photonics is a revolutionary technology in the integrated photonics field which has experienced rapid development over the past several decades. High-quality III-V semiconductor components on Si platforms have shown their great potential to realize on-chip light-emitting sources for Si photonics with low-cost and high-density integration. In this review, we will focus on semiconductor optical amplifiers (SOAs), which have received considerable interest in diverse photonic applications. SOAs have demonstrated high performance in various on-chip optical applications through different integration technologies on Si substrates. Moreover, SOAs are also considered as promising candidates for future light sources in the wavelength tunable laser, which is one of the key suitable components in coherent optical devices. Understanding the development and trends of heterogeneous integration Silicon/III-V SOA will help researchers to come up with effective strategies to combat the emerging challenges in this family of devices, progressing towards next-generation applications.

Semiconductor lasers are widely used in incoherent/coherent optical communications, optical fiber sensing, and lidar due to their small size, high efficiency, and immunity to vibrations. To support the continuous evolution of these high-performance application systems, the noise characteristics of semiconductor lasers play a key role and the noise levels need to be reduced to unprecedentedly low values (such as quantum limit). In this paper, a comprehensive overview on the principles, measurements, and suppressions of semiconductor laser noises are provided. First, we introduce the analysis models and key performance indicators of semiconductor lasers related to noise. Then, different noise measurement systems are investigated for semiconductor lasers and the noise characteristics are fully analyzed. Next, the noise suppression methods towards semiconductor lasers are demonstrated from three aspects: the chip structures, the external cavity optical feedback technology and the driving and controlling circuits. Finally, we summarize the recent advances on the noise measurement and suppression of semiconductor laser, future prospects are also discussed.

We report on a memory structure that only makes use of holes as the storage charges based on type-II GaSb/GaAs quantum dots (QDs) using an AlGaAs barrier. The C-V measurements confirm existence of quantum states in the GaSb dots and reveal the applied bias voltage range for the write/erase process by charging/discharging the QDs. A large hole activation energy value of 540 meV is obtained for the device measured by deep level transient spectroscopy. Our results indicate that type-II GaSb/GaAs QD system is a promising candidate for future memory devices.

We report on a short/mid-wave (SW/MW) two-band type-II InAs/GaSb superlattice infrared heterojunction phototransistor (HPT). The structure consists of two back-to-back HPTs for the SW and MW detections. At 77 K, the 50% cutoff wavelength of the SW and MW HPT is 2.6 and 4.2 μm, respectively. When the applied bias voltage is 1.2 V, the responsivity is 213 A/W and the current gain is 611 for the SW band, while for the MW band, the responsivity is 45.2 A/W and the current gain is 377 at bias voltage of 1.3 V. At 1.2 V, the shot noise limited detectivity D* of the SW channel and the MW channel is 1.9 × 10 ¹¹ and 1.7 × 10 ⁹ cm · Hz ^0.5 /W, respectively.

We report a specially designed p-i-n quantum dot (QD) device in which both the intersubband and the interband transitions of the QD are controlled by the applied forward bias voltage. The design is achieved by using asymmetric AlGaAs barriers on both sides of only one QD layer and by placing two-dimensional electron gas structure on one side of the QD layer. Experimentally, at 77 K, the device can detect normal incidence infrared light of about 5.6 µm when the forward bias voltage is in between about 3 and 7 V, while it emits electroluminescence of about 1 μm when the applied forward bias voltage is larger than 11 V.

We report on a mid wavelength (MW) type II InAs/GaSb superlattice (SL) photodetector structure using SiO_xN_y as the passivation material. The 50% cutoff wavelength of the photoresponse is 4.8 µm at 77 K. R₀A, the resistance-and-area product at zero bias, is 2.1×10³ Ωcm² for the device with the SiO_xN_y passivation, which is about 13 times larger than that without the passivation. Our result indicates SiO_xN_y passivation is an effective way to reduce the shunt current for MW InAs/GaSb SL photodetector.