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GaN power electronic devices, such as the lateral AlGaN/GaN Schottky barrier diode (SBD), have received significant attention in recent years. Many studies have focused on optimizing the breakdown voltage (BV) of the device, with a particular emphasis on achieving ultra-high-voltage (UHV, > 10 kV) applications. However, another important question arises: can the device maintain a BV of 10 kV while having a low turn-on voltage (V_on)? In this study, the fabrication of UHV AlGaN/GaN SBDs was demonstrated on sapphire with a BV exceeding 10 kV. Moreover, by utilizing a double-barrier anode (DBA) structure consisting of platinum (Pt) and tantalum (Ta), a remarkably low V_on of 0.36 V was achieved. This achievement highlights the great potential of these devices for UHV applications.

Low temperature complementary metal oxide semiconductor (CMOS) or cryogenic CMOS is a promising avenue for the continuation of Moore's law while serving the needs of high performance computing. With temperature as a control “knob” to steepen the subthreshold slope behavior of CMOS devices, the supply voltage of operation can be reduced with no impact on operating speed. With the optimal threshold voltage engineering, the device ON current can be further enhanced, translating to higher performance. In this article, the experimentally calibrated data was adopted to tune the threshold voltage and investigated the power performance area of cryogenic CMOS at device, circuit and system level. We also presented results from measurement and analysis of functional memory chips fabricated in 28 nm bulk CMOS and 22 nm fully depleted silicon on insulator (FDSOI) operating at cryogenic temperature. Finally, the challenges and opportunities in the further development and deployment of such systems were discussed.

With the increasing number of ion qubits and improving performance of sophisticated quantum algorithms, more and more scalable complex ion trap electrodes have been developed and integrated. Nonlinear ion shuttling operations at the junction are more frequently used, such as in the areas of separation, merging, and exchanging. Several studies have been conducted to optimize the geometries of the radio-frequency (RF) electrodes to generate ideal trapping electric fields with a lower junction barrier and an even ion height of the RF saddle points. However, this iteration is time-consuming and commonly accompanied by complicated and sharp electrode geometry. Therefore, high-accuracy fabrication process and high electric breakdown voltage are essential. In the current work, an effective method was proposed to reduce the junction's pseudo-potential barrier and ion height variation by setting several individual RF electrodes and adjusting each RF voltage amplitude without changing the geometry of the electrode structure. The simulation results show that this method shows the same effect on engineering the trapping potential and reducing the potential barrier, but requires fewer parameters and optimization time. By combining this method with the geometrical shape-optimizing, the pseudo-potential barrier and the ion height variation near the junction can be further reduced. In addition, the geometry of the electrodes can be simplified to relax the fabrication precision and keep the ability to engineer the trapping electric field in real-time even after the fabrication of the electrodes, which provides a potential all-electric degree of freedom for the design and control of the two-dimensional ion crystals and investigation of their phase transition.

Two-dimensional (2D) van der Waals materials have attracted great interest and facilitated the development of post-Moore electronics owing to their novel physical properties and high compatibility with traditional microfabrication techniques. Their wafer-scale synthesis has become a critical challenge for large-scale integrated applications. Although the wafer-scale synthesis approaches for some 2D materials have been extensively explored, the preparation of high-quality thin films with well-controlled thickness remains a big challenge. This review focuses on the wafer-scale synthesis of 2D materials and their applications in integrated electronics. Firstly, several representative 2D layered materials including their crystal structures and unique electronic properties were introduced. Then, the current synthesis strategies of 2D layered materials at the wafer scale, which are divided into “top-down” and “bottom-up”, were reviewed in depth. Afterwards, the applications of 2D materials wafer in integrated electrical and optoelectronic devices were discussed. Finally, the current challenges and future prospects for 2D integrated electronics were presented. It is hoped that this review will provide comprehensive and insightful guidance for the development of wafer-scale 2D materials and their integrated applications.

Solution-processed colloidal semiconductor nanocrystals (NCs) have become attractive materials for the development of optoelectronic and photonic devices due to their inexpensive synthesis and excellent optical properties. Recently, CdSe NCs with different dimensions and structures have achieved significant progress in photonic integrated circuits (PICs), including light generation (laser), guiding (waveguide), modulation, and detection on a chip. This article summarizes the development of CdSe NCs–based lasers and discusses the challenges and opportunities for the application of CdSe NCs in PICs. Firstly, an overview of the optical properties of CdSe-based NCs with different dimensions is presented, with emphasis on the amplified stimulated emission and laser properties. Then, the nanophotonic devices and PICs based on CdSe NCs are introduced and discussed. Finally, the prospects for PICs are addressed.

Superconducting nanowire single-photon detectors (SNSPDs) have become a mainstream photon-counting technology that has been widely applied in various scenarios. So far, most multi-channel SNSPD systems, either reported in literature or commercially available, are polarization sensitive, that is, the system detection efficiency (SDE) of each channel is dependent on the state of polarization of the to-be-detected photons. Here, we reported an eight-channel system with fractal SNSPDs working in the wavelength range of 930 to 940 nm, which are all featured with low polarization sensitivity. In a close-cycled Gifford-McMahon cryocooler system with the base temperature of 2.2 K, we installed and compared the performance of two types of devices: (1) SNSPD, composed of a single, continuous nanowire and (2) superconducting nanowire avalanche photodetector (SNAP), composed of 16 cascaded units of two nanowires electrically connected in parallel. The highest SDE among the eight channels reaches ${96}_{-5}^{+4}$%, with the polarization sensitivity of 1.02 and a dark-count rate of 13 counts per second. The average SDE for eight channels for all states of polarization is estimated to be 90 ± 5%. It is concluded that both the SNSPDs and the SNAPs can reach saturated, high SDE at the wavelength of interest, and the SNSPDs show lower dark-count (false-count) rates, whereas the SNAPs show better properties in the time domain. With the adoption of this system, we showcased the measurements of the second-order photon-correlation functions of light emission from a single-photon source based on a semiconductor quantum dot and from a pulsed laser. It is believed that this work will provide new choices of systems with single-photon detectors combining the merits of high SDE, low polarization sensitivity, and low noise that can be tailored for different applications.

As a typical representative of nanomaterials, carbon nanomaterials have attracted widespread attention in the construction of electronic devices owing to their unique physical and chemical properties, multi-dimensionality, multi-hybridization methods, and excellent electronic properties. Especially in the recent years, memristors based on carbon nanomaterials have flourished in the field of building non-volatile memory devices and neuromorphic applications. In the current work, the preparation methods and structural characteristics of carbon nanomaterials of different dimensions were systematically reviewed. Afterwards, in depth discussion on the structural characteristics and working mechanism of memristors based on carbon nanomaterials of different dimensions was conducted. Finally, the potential applications of carbon-based memristors in logic operations, neural network construction, artificial vision systems, artificial tactile systems, and multimodal perception systems were also introduced. It is believed that this paper will provide guidance for the future development of high-quality information storage, high-performance neuromorphic applications, and high-sensitivity bionic sensing based on carbon-based memristors.

Building communication links among multiple users in a scalable and robust way is a key objective in achieving large-scale quantum networks. In a realistic scenario, noise from the coexisting classical light is inevitable and can ultimately disrupt the entanglement. The previous significant fully connected multiuser entanglement distribution experiments are conducted using dark fiber links, and there is no explicit relation between the entanglement degradations induced by classical noise and its error rate. Here, a semiconductor chip with a high figure-of-merit modal overlap is fabricated to directly generate broadband polarization entanglement. The monolithic source maintains the polarization entanglement fidelity of above 96% for 42 nm bandwidth, with a brightness of 1.2 × 10⁷ Hz mW⁻¹. A continuously working quantum entanglement distribution are performed among three users coexisting with classical light. Under finite-key analysis, secure keys are established and images encryption are enabled as well as quantum secret sharing between users. This work paves the way for practical multiparty quantum communication with integrated photonic architecture compatible with real-world fiber optical communication network.

The development of large-scale quantum computing has boosted an urgent desire for the advancement of cryogenic CMOS (cryo-CMOS), which is a promising scalable solution for the control and read-out interface of quantum bits. In the current work, 180 nm CMOS transistors were characterized and modeled down to 4 K, and the impact of low-temperature transistor performance variations on circuit design was also analyzed. Based on the proposed cryogenic model, a 180 nm CMOS-based 450 to 850 MHz clock generator operating at 4 K for quantum computing applications was presented. At the output frequency of 600 MHz, it achieved < 4.8 ps RMS jitter with 30 mW power consumption (with test buffer), corresponding to a −211.6 dB jitter-power FOM, which is suitable for providing a stable clock signal for the control and readout electronics of scalable quantum computers.

This paper provides a comprehensive review of advanced radio frequency (RF) filter technologies available in miniature chip or integrated circuit (IC) form for wireless communication applications. The RF filter technologies were organized according to the timeline of their introduction, in conjunction with each generation of wireless (cellular) communication standards (1G to 5G). This approach enabled a clear explanation of the corresponding invention history, working principles, typical applications and future development trends. The article covered commercially successful acoustic filter technologies, including the widely used surface acoustic wave (SAW) and bulk acoustic wave (BAW) filters, as well as electromagnetic filter technologies based on low-temperature co-fired ceramic (LTCC) and integrated passive device (IPD). Additionally, emerging filter technologies such as IHP-SAW, suspended thin-film lithium niobate (LiNbO₃ or LN) resonant devices and hybrid were also discussed. In order to achieve higher performance, smaller form factor and lower cost for the wireless communication industry, it is believed that fundamental breakthroughs in materials and fabrication techniques are necessary for the future development of RF filters.