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To meet the current requirements of diluted magnetic semiconductors (DMSs) resulting from continuous advancements in spintronics, designing d0 DMSs with high stability, spin polarization, and Curie temperature is essential. Present research on introducing d0 magnetism is limited to monatomic doping, lacking regulation measures for local magnetic moments and long range magnetic coupling. Herein, an adjacent doping strategy is employed to introduce degrees of freedom for tuning the magnetic properties of d0 DMSs. It is observed that by introducing Si and O atoms as central and adjacent dopants, respectively, the intrinsically nonmagnetic hexagonal boron nitride (h-BN) exhibits significant local magnetic moments. Furthermore, it is observed that the ionization energy, total magnetic moment, magnetic coupling, and Curie temperature of the doped h-BN are susceptible to the Si–O coordination. Subsequently, a magnetic half-metal (Si–O3-doped h-BN) with high thermal stability, 100% spin polarization, long range ferromagnetic coupling, and high Curie temperature is designed through high Si–O coordination doping. This study proposes a feasible approach for introducing tunable d0 magnetism using the design of Si–O adjacent-doped h-BN as an example. [ABSTRACT FROM AUTHOR]

Van der Waals heterostructure based on 2D materials is a promising technology for high-performance optoelectronic devices because of its tunable bandgaps and optical properties. However, photodetectors with a low dark current and a fast response speed commonly lose their photoresponsivity. The recovery current induced by the Schottky barrier height variation cancels out the device's reverse bias current in this paper, resulting in a quasi-vertical MoSe2 photodiode with ultralow dark current (<1 pA). Simultaneously, rapid electron–hole pair separation occurs at the interface due to the large heterojunction area and the strong interlayer coupling of MoSe2/graphene heterojunction, resulting in a fast response time of 1.5 ms and a high photoresponsivity of 19.72 A/W. Furthermore, the Au/MoSe2 forms a Schottky contact, which is asymmetrical to the Ohmic contact formed by the MoSe2/graphene, enabling the proposed device to achieve high-performance self-powered photodetection. Our work shows an alternative approach to improve the performance of future electronic and optoelectronic applications. [ABSTRACT FROM AUTHOR]

With the constant scaling down of transistors, "More Moore" has put forward requirements for channel materials. Two-dimensional materials are considered as potential next-generation channel materials due to their unique physical properties. Herein, we study the ballistic transport characteristics of sub-10 nm monolayer (ML) planar GaN metal–oxide–semiconductor field-effect transistors (MOSFETs) based on density functional theory and the non-equilibrium Green's function method. The calculation results indicate that n-type ML planar GaN MOSFETs with gate lengths not less than 5 nm exhibit excellent subthreshold characteristics, fast switching speeds, and low switching energies, and the corresponding parameters (off-current, on-current, delay time, and power-delay product) can simultaneously meet the requirements of the International Roadmap for Devices and Systems for the 2028 horizon for high-performance and low-power applications. Therefore, ML planar GaN is predicted to be a reliable next-generation channel material to extend Moore's law. [ABSTRACT FROM AUTHOR]

In this work, an enhancement-mode (E-mode) β-Ga2O3 metal-oxide-semiconductor field-effect transistor (MOSFET) has been achieved by incorporating a laminated-ferroelectric charge storage gate (L-FeG) structure [Al2O3/HfO2/Al2O3/Hf0.5Zr0.5O2 (HZO) of 10/5/2/16 nm]. The band diagram between L-FeG dielectrics (Al2O3, HfO2, and HZO) and β-Ga2O3 was determined by x-ray photoelectron spectroscopy. After applying a gate pulse with an intensity of +18 V and width of 1 ms, the saturation current of the E-mode device was measured to be 23.2 mA/mm, which shows a negligible current reduction compared to that of 22.1 mA/mm in a depletion- (D-) mode device. In addition, the threshold voltage (VTH) is only shifted by 2.76% and 2.18%, respectively, after applying the gate stress and gate-drain stress of 15 V for 104 s. Meanwhile, a high breakdown voltage of 2142 V and specific on-resistance (RON,sp) of 23.84 mΩ·cm2 were also achieved, which correspond to a state-of-art high power figure of merit of 192.5 MW/cm2, showing the great potential of combing the ferroelectric gate stack and lateral Ga2O3 MOSFET as next generation power devices. [ABSTRACT FROM AUTHOR]