Remote epitaxy and exfoliation of vanadium dioxide via sub-nanometer thick amorphous interlayer.

The recently emerged remote epitaxy technique, utilizing 2D materials (mostly graphene) as interlayers between the epilayer and the substrate, enables the exfoliation of crystalline nanomembranes from the substrate, expanding the range of potential device applications. However, remote epitaxy has been so far applied to a limited range of material systems, owing to the need of stringent growth conditions to avoid graphene damaging, and has therefore remained challenging for the synthesis of oxide nanomembranes. Here, we demonstrate the remote epitaxial growth of an oxide nanomembrane (vanadium dioxide, VO) with a sub-nanometer thick amorphous interlayer, which can withstand potential sputtering-induced damage and oxidation.

Enhanced photothermoelectric conversion in self-rolled tellurium photodetector with geometry-induced energy localization.

Photodetection has attracted significant attention for information transmission. While the implementation relies primarily on the photonic detectors, they are predominantly constrained by the intrinsic bandgap of active materials. On the other hand, photothermoelectric (PTE) detectors have garnered substantial research interest for their promising capabilities in broadband detection, owing to the self-driven photovoltages induced by the temperature differences.

Multilevel design and construction in nanomembrane rolling for three-dimensional angle-sensitive photodetection.

Releasing pre-strained two-dimensional nanomembranes to assemble on-chip three-dimensional devices is crucial for upcoming advanced electronic and optoelectronic applications. However, the release process is affected by many unclear factors, hindering the transition from laboratory to industrial applications. Here, we propose a quasistatic multilevel finite element modeling to assemble three-dimensional structures from two-dimensional nanomembranes and offer verification results by various bilayer nanomembranes.

One-step rolling fabrication of VO tubular bolometers with polarization-sensitive and omnidirectional detection.

Uncooled infrared detection based on vanadium dioxide (VO) radiometer is highly demanded in temperature monitoring and security protection. The key to its breakthrough is to fabricate bolometer arrays with great absorbance and excellent thermal insulation using a straightforward procedure. Here, we show a tubular bolometer by one-step rolling VO nanomembranes with enhanced infrared detection.

Self-Rolled-Up Ultrathin Single-Crystalline Silicon Nanomembranes for On-Chip Tubular Polarization Photodetectors.

Freestanding single-crystalline nanomembranes and their assembly have broad application potential in photodetectors for integrated chips. However, the release and self-assembly process of single-crystalline semiconductor nanomembranes still remains a great challenge in on-chip processing and functional integration, and photodetectors based on nanomembrane always suffer from limited absorption of nanoscale thickness. Here, a non-destructive releasing and rolling process is employed to prepare tubular photodetectors based on freestanding single-crystalline Si nanomembranes.

Ferroelectric-tuned van der Waals heterojunction with band alignment evolution.

Van der Waals integration with abundant two-dimensional materials provides a broad basis for assembling functional devices. In a specific van der Waals heterojunction, the band alignment engineering is crucial and feasible to realize high performance and multifunctionality. Here, we design a ferroelectric-tuned van der Waals heterojunction device structure by integrating a GeSe/MoS VHJ and poly (vinylidene fluoride-trifluoroethylene)-based ferroelectric polymer.

End-Bonded Contacts of Tellurium Transistors.

The development of novel low-dimensional materials makes the metallic contact to nanostructure facing challenges. Compared to side contacts, end-bonded contacts are proposed to be more effective pathways for charge injection and extraction. However, there is a lack of up-to-date understanding regarding end-bonded contacts, especially the recently emerged high-performance field-effect transistors (FETs).

A versatile photodetector assisted by photovoltaic and bolometric effects.

The advent of low-dimensional materials with peculiar structure and superb band properties provides a new canonical form for the development of photodetectors. However, the limited exploitation of basic properties makes it difficult for devices to stand out. Here, we demonstrate a hybrid heterostructure with ultrathin vanadium dioxide film and molybdenum ditelluride nanoflake.

Multifunctional MoS Transistors with Electrolyte Gel Gating.

MoS , one of the most valued 2D materials beyond graphene, shows potential for future applications in postsilicon digital electronics and optoelectronics. However, achieving hole transport in MoS , which is dominated by electron transport, is always a challenge. Here, MoS transistors gated by electrolyte gel exhibit the characteristics of hole and electron transport, a high on/off ratio over 10 , and a low subthreshold swing below 50 mV per decade.

MoTe p-n Homojunctions Defined by Ferroelectric Polarization.

Doped p-n junctions are fundamental electrical components in modern electronics and optoelectronics. Due to the development of device miniaturization, the emergence of two-dimensional (2D) materials may initiate the next technological leap toward the post-Moore era owing to their unique structures and physical properties. The purpose of fabricating 2D p-n junctions has fueled many carrier-type modulation methods, such as electrostatic doping, surface modification, and element intercalation.

Multimode Signal Processor Unit Based on the Ambipolar WSe-Cr Schottky Junction.

A Schottky barrier is a double-edged sword in electronic and optoelectronic devices, especially devices based on two-dimensional materials. It may restrict the carrier transport in devices, but it can also realize multifunctional devices by architecture design. We designed a simple but novel device structure based on theWSe-Cr Schottky junction with an asymmetric Schottky contact area of the source and drain.