Engineering semiconductor heterojunctions is a pivotal research frontier for developing next-generation optoelectronic devices, particularly for neuromorphic computing. However, performing precise, stimulus-selective control over interfacial carrier dynamics to unlock advanced memory and logic functions remains a significant challenge. Herein, we unveil a novel "photon-energy-gated selective carrier accumulation" mechanism within macroscopically ordered ZnO/Ga2O3 core-shell nanowire heterojunctions, governed by the Type-I band alignment at the heterointerface. This unique architecture, fabricated via a super-aligned carbon nanotube template, not only boosts the UV photoresponsivity by 78-fold compared to pure ZnO counterparts but also enables a remarkable wavelength-selective activation of persistent photoconductivity. Harnessing this optically switchable memory effect, we demonstrate its application in optoelectronic synaptic devices, and we also prove its potential in physical reservoir computing system, achieving a high classification accuracy of 87.9% on the Fashion - Modified National Institute of Standards and Technology (F-MNIST) dataset. This study provides a new paradigm for designing intelligent optoelectronic devices by precisely manipulating interfacial carrier dynamics, opening promising avenues for in-sensor computing and advanced photonic memory.

Nanofluidic memristors, exploiting ion transport in nanochannels, hold promise for neuromorphic applications. A planar architecture is particularly desired for scalable integration with established micro- and nanofabrication technologies. Here, using the Poisson-Nernst-Planck framework, we theoretically propose planar nanofluidic memristors enabled by surface charge gradient, providing an alternative to the commonly used geometrically asymmetric architectures. The resulting memristive behavior is governed by a diffusion-mediated secondary enrichment effect. By systematically solving the PNP equations, we obtain the scaling of the characteristic memory time across the parameter space. We also reveal that the memory effect is related to the first-order moment of surface charge, for arbitrary charge profiles. These results provide a theoretical basis for rationally designing and optimizing planar nanofluidic memristors through spatially patterned surface charge.

Alternating twisted multilayer graphene presents a compelling multiband system, with a coexistence of Dirac bands and flat bands, for exploring superconductivity. However, the roles of flat bands and Dirac bands played in determining the superconductivity remain elusive. Here, we focus on the alternating twisted quadralayer graphene to reveal unconventional superconducting behaviors. We disentangle Dirac bands and flat bands, revealing a Coulomb interaction-induced band broadening effect. We further quantify the electric-field-dependent evolution of the critical temperature and coherence length, and estimate the flat-band Fermi velocity and superfluid stiffness via critical current measurements. Our results demonstrate an electric-field–tunable coupling strength within the superconducting phase, revealing unconventional properties with vanishing Fermi velocity and large superfluid stiffness. Combined with our theoretical analysis, these observations support a picture in which displacement-field-driven hybridization between flat and Dirac-like bands enhances the quantum-metric contribution to superconductivity, offering new insight into multiband flat-band superconductivity in moiré systems. The authors study flat-band superconductivity in alternating twisted quadra-layer graphene by transport, finding an electric-field-tunable coupling strength within the superconducting phase, vanishing Fermi velocity and large superfluid stiffness. They attribute these phenomena to quantum metric contributions, mediated by hybridization of Dirac bands and flat bands.

Nanofluidic devices prompts unconventional ion transports appealing to energy and information technologies, thanks to the susceptibility of confined electric double layers (EDL) to various external physical fields. Although experimental studies advance rapidly, the rationalization of field-tunable nanofluidic transports has not reached a formalized and unified level. Here we formally reformulate the Poisson-Boltzmann theory and reveal distinct EDL regimes on the parameter space. Based on the regime classification, we establish a formal framework for the tunable nanofluidic transport, which reproduces the observed conductivity-concentration scaling behaviors, rationalizes the ionic transistors with reconfigurable polarities, and predicts two fundamental thermodynamic limits for electrostatic modulation (60 mV/dec and 120 mV/dec). Being accurate, generalizable and extensible, this framework can account for a wide range of ion transports in confined spaces.

Twisted graphene moire superlattice has been demonstrated as an exotic platform for investigating correlated states and nontrivial topology. Among the moire family, twisted double bilayer graphene (TDBG) is a tunable flat band system expected to show stacking-dependent topological properties. However, electron correlations and the band topology are usually intertwined in the flat band limit, rendering the unique topological property due to stacking still elusive. Focusing on a large-angle TDBG with weak electron correlations, here we probe the Landau level (LL) spectra in two differently stacked TDBG, i.e. ABBA- and ABAB-TDBG, to unveil their distinct topological properties. For ABBA-TDBG, we observe non-trivial topology at zero electric displacement filed, evident from both the emergence of Chern bands from half fillings and the closure of gap at CNP above a critical magnetic field. For ABAB-TDBG, by contrast, we find that the moire band is topologically trivial, supported by the absence of LLs from half fillings and the persistence of the gap at CNP above the critical magnetic fields. In addition, we also observe an evolution of the trivial-to-nontrivial topological transition at finite D fields, confirmed by the emerged Landau fans originating from quarter filling v = 1. Our result demonstrates, for the first time, the unique stacking-dependent topology in TDBG, offering a promising avenue for future investigations on topological states in correlated systems.

Superconductivity in flatband systems has attracted tremendous attention in condensed matter physics. Alternating twisted multilayer graphene presents a compelling multiband system, with a coexistence of Dirac bands and flat bands, for exploring superconductivity. However, the roles of flat bands and dispersive bands played in determining the superconductivity remain elusive. Here, we focus on the alternating twisted quadralayer graphene to reveal unconventional superconducting behaviors by systematically quantifying individual contributions for both the dispersive bands and the flat bands. The superconductivity is robust, with a strong electrical field tunability, a maximum BKT transition temperature of 1.6 K, and high critical magnetic fields beyond the Pauli limit. By analyzing the Landau fan diagram at zero electric displacement fields, we disentangle Dirac bands and flat bands, revealing a Coulomb interaction-induced band broadening effect. We further quantify the electric-field-dependent evolution of the critical temperature and coherence length, and estimate the flat-band Fermi velocity and superfluid stiffness via critical current measurements. Our results demonstrate an electric field tunable coupling strength within the superconducting phase, revealing unconventional properties with vanishing Fermi velocity and large superfluid stiffness. These phenomena, attributed to substantial quantum metric contributions mediated by Dirac band hybridization, offer new insights into the mechanisms underlying unconventional flatband superconductivity in moiré systems.

The silicon-based field-effect transistor (FET) is approaching the physical limits for the prominent short-channel effects and the sequent leakage currents under the conventional paradigm. Here, we propose a momentum-dependent field-effect transistor (MD-FET) to address this issue, in which a monolayer 2D semiconductor is sandwiched by two cross 1D carbon nanotube electrodes. The MD-FET enables a perfect off state, as the elastic tunneling is forbidden by the momentum mismatch between the cross 1D contacts. It can also access a substantial on state, because the momentum mismatch can be compensated by the electron-phonon scattering in a 2D channel. The MD-FET with sub-1-nm channel thus exhibits high on/off ratios of ~107, which breaks through the theoretical limit on the short-channel effect. The MD-FET opens up a previously unknown paradigm to further scale down transistors beyond silicon and inspires a promising solution for the post-Moore era.

For applications of single-walled carbon nanotubes (SWNTs) in integrated circuits, it is crucial to have high–tube density arrays of SWNTs that are well aligned and purely semiconducting. In this work, we report on the direct growth of close-packed SWNT arrays on hexagonal boron nitride (hBN) substrates, demonstrating high alignment and uniform chirality within each array. Molecular dynamics simulations suggest that a self-assembly growth mechanism resulted from the intertube van der Waals attraction and the ultralow sliding friction of SWNTs on the atomically flat hBN substrate. Field-effect transistors constructed from the grown SWNT array exhibit high performance at room temperature, with mobilities of up to 2000 square centimeters per volt per second, on/off ratios of ~10 7 , and a maximum current density of ~6 milliamperes per micrometer.

ABSTRACT Biomimetic visual perception and processing have gained increasing prominence in advancing vision restoration technologies and developing next‐generation human‐machine interfaces. As dual fundamental parameters for environmental information capture, light intensity and color perception constitute essential dimensions in visual signal acquisition. While digital encoding remains a conventional approach, the biomimetic frequency coding approach is considered to be an efficient input method for simulating the retina neural architecture in artificial vision systems. Here, we fabricated molybdenum disulfide (MoS2) based ring oscillators for color and intensity resolved image recognition, which exploit wavelength‐dependent photoresponsivity (400–700 nm) to implement biomimetic spectral coding. Through MoS2 oscillators, light signals are transduced into frequency‐modulated electrical spikes from 265 Hz to 3.8 kHz, establishing hardware foundations for chromatic opponency processing in neuromorphic visual systems. This orthogonal signal modulation strategy enables cross‐talk‐free transmission of visual information, effectively decoupling wavelength‐dependent chromatic data from intensity‐modulated luminance signals. By integrating the obtained oscillatory signals into a convolutional neural network system, we successfully demonstrated the device's applicability in amplifying subtle differences in color and texture features in image recognition and thus realizing high dynamic range encoding and robust feature extraction.

Continuous monitoring of intraocular pressure (IOP) is critical for the diagnosis and management of glaucoma. Flexible piezoresistive wearable devices, featuring high sensitivity and simple signal processing, enable such continuous monitoring. Recently, conductive metal-organic frameworks (MOFs) have shown promising potential in electronic devices due to their coordination self-assembly, which allows integration with various complex substrates for wearable sensor applications. Here, we present a flexible piezoresistive sensor with a layered fiber structure, achieved through in situ assembly of Cu3(HHTP)2 on poly(ether sulfone) (PES) fibers using a template method. The resulting sensor exhibits excellent signal stability, high sensitivity (8.10 kPa-1), a rapid response time (34 ms), and over 10,000 cycles of stability. Additionally, finite element analysis of corneal stress guided the design and fabrication of an IOP sensor encapsulated in a polydimethylsiloxane (PDMS) contact lens. Preliminary feasibility of the sensor was validated through tests on porcine eye, demonstrating its potential for wearable human applications.

Two-dimensional moiré superlattices have been extensively studied, and a variety of correlated phenomena have been observed. However, their lower-dimensional counterpart, one-dimensional (1D) moiré superlattices, remain largely unexplored. Electrons in 1D are generally described by Luttinger liquid theory, with universal scaling relations depending only on the Luttinger parameter g. In particular, at half-filling, Umklapp scattering plays a crucial role, as it can significantly change the conductance-temperature scaling relation and lead to Mott insulators. However, this prediction has never been observed since doping an empty band to half-filling was extremely difficult. Here, we show that the marriage of moiré superlattices and 1D electrons makes it possible to study the Luttinger liquid in an exceptionally wide filling region simply by electrical gating. We perform transport measurements on 1D moiré superlattices of carbon nanotubes on hexagonal boron nitride (hBN) substrates, and observe correlated insulating states at 1/4 and 1/2 fillings of the superlattice mini-band, where Umklapp scattering becomes dominant. We also observe a T-linear conductance at these commensurate fillings over a range of temperatures. Strikingly, the T-linear conductance leads to a strongly suppressed Luttinger parameter, suggesting a state of extreme correlation.

Moiré flatbands with high Chern numbers (C>1) offer opportunities to study the fractional quantum anomalous Hall effects that go beyond the Landau level paradigm with C=1, which remain unexplored yet. Here, we target the novel topological phases in high Chern number flatbands by designing a new moiré system, i.e., twisted rhombohedral trilayer-bilayer graphene. We observe quantized anomalous Hall effects (QAH) with C = 3 at v = 1 and v = 3, demonstrating the high Chern number nature of the flat band from continuum calculations. By fractionally filling the flat band, we observe QAH with C = 2 at even-denominator fractional filling v = 3/2, as well as QAH with C = 3 continuously from v = 1 to the even-denominator v = 3/2 at zero magnetic fields. Most importantly, we observe, for the first time, evidence of an FCI with C = -6/5 at v = 12/5, corresponding to 2/5 filling of a high Chern number flat band with C = -3, verified by both Streda formula analysis and a fractionally QAH. It is also worth noting that Streda formula analysis reveals a signature of another FCI with C = -3/2 at v = 5/2 under finite magnetic fields. Our results demonstrate the tRTBG, which can be naturally extended to other twisted graphene moiré superlattices based on rhombohedral graphene multilayers, as a novel platform for hosting unconventional high Chern number correlated topology in the ultra-strong correlated regime that is beyond the paradigm of fractional phases with C < 1.

AbstractReconfigurable low‐dimensional devices are attractive for electronics in the post‐Moore era. However, their performance and function design are limited by the metal–semiconductor contacts for the Fermi level pinning and fixed Schottky barrier height (SBH). Here, semimetal carbon nanotube (sCNT) contacts are incorporated into a WSe2 transistor to address these issues. The transistor exhibits excellent ambipolar transfer characteristics with on/off ratio exceeding 107 for both hole and electron conduction. Furthermore, the output characteristics are reconfigured among the four equivalent modes, P–P, P–N, N–P, and N–N, by applying appropriate gate voltage. The significant forward and backward rectifying behaviors at P‐N and N‐P modes are highly symmetrical and have high rectification ratios of over 106. The improvements are attributed to specific semimetal contacts for the gate‐tunable SBH and the drain‐induced Schottky barrier lowering (DISBL) effect. Practical circuits include a reconfigurable filter circuit and a logic invertor have been further demonstrated successfully. The progress reveals that the semimetal contacts have great potential in future reconfigurable devices and circuits.

Contact engineering at the semiconductor–electrode and semiconductor–dielectric interfaces is critical to the performance of electronic devices, especially for delicate 2D semiconductors. Here, this study proposes a new paradigm of flexible field‐effect transistors featuring solid–liquid hybrid interfaces, in which liquid metal and ionic liquid, confined within microchannels, function as the source/drain electrodes and gate dielectric, respectively. These interfaces provide MoS₂ with undisturbed, atomically smooth electrical contacts, and enable efficient gate control via electric double layers. Benefiting from the inherent softness of liquids and their damage‐free processing, Fermi level pinning is significantly mitigated by the liquid metal, achieving a pinning factor |s| = 0.7. Meanwhile, the ionic liquid enables a subthreshold swing of 60.7 mV dec −1 , approaching the theoretical thermal limit. Furthermore, our flexible transistors demonstrate multifunctionality as enhanced logic gates, low‐voltage inverters, and ultra‐high‐linearity synaptic devices. This work underscores the promise of liquid‐enabled contact strategies for advancing low‐power, flexible electronics and soft robotic systems.

Molecular dynamics simulations were first employed to investigate effect of grain Size(D = 6-15 nm) on the interface deformation mechanism and mechanical properties of polycrystalline Cu/Al2Cu/Al layered Composite Materials. The results showed that tensile strength decreased significantly with increasing grain size, while Young's modulus exhibited an increasing trend. The average flow stress peaked at a critical grain size of D = 12 nm, corresponding to a transition in the dominant deformation mechanism from grain boundary migration to dislocation slip. By adjusting grain size, a balance between strength and ductility was achieved, resulting in excellent overall mechanical performance. Size-dependent responses primarily originated from grain-regulated interface shear strain and dislocation density redistribution. Grain size had minimal influence on the fracture mechanism. Cracks consistently initiated at the Al2Cu grain boundary and propagated laterally, displaying characteristics of brittle fracture. A decrease in grain size led to reduced failure strain, and higher stress was required to initiate crack propagation. Crack propagation behavior exhibited a strong dependence on grain size. At the critical size of D = 12 nm, crack tip blunting effectively suppressed microvoid formation and crack advancement. Dislocation density and mobility were identified as key factors underlying the pronounced size effect in polycrystalline Cu/Al2Cu/Al interfaces. These findings clarify the competing mechanisms underlying the strength-ductility trade-off influenced by grain size and provide theoretical and practical insights for microstructural design and optimization of intermetallic compound interface materials.

Graphene nanoribbons (GNRs) are highly promising for exploring one-dimensional (1D) correlation physics and constructing digital logic circuits. Here, we report the intrinsic electrical transport behaviors of GNR field-effect transistors (FETs) fabricated using GNRs in situ encapsulated by hexagonal boron nitride (hBN) flakes. The FET devices exhibit excellent performance at room temperature: mobility up to ∼5000 cm2 V-1 s-1, on/off ratio up to ∼106, and subthreshold swing down to ∼70 mV dec-1. The devices exhibit periodic conductance peaks and regular Coulomb diamonds due to strong electron-electron repulsion at cryogenic temperatures. Additionally, conductance of the GNR devices exhibits power-law dependence and universal scaling, signatures of Luttinger liquid behaviors, with a tunable Luttinger parameter g ranging from 0.1 to 0.3. Our study demonstrates that the in situ encapsulated GNRs can function as both high-performance FET devices and strongly interacting 1D quantum systems, providing an ideal platform for studying 1D transport and correlated physics.

The utilization of functional fillers in the development of composite materials has come a long way since its advent to improve physical, chemical, or mechanical properties of the base material. However, the heterogenous roles contributed by a single type of filler remain uncommon in this field. Here the endowment of various modifications to a 1,8-octanediol/1,12-dodecanedioic acid/citric acid (OD/DDA/CA) matrix through the incorporation of iron oxide nanoparticles (IONPs) is reported. Owing to the relaxation and hysteresis loss behaviors of IONPs when exposed to an alternating magnetic field (AMF), the composites demonstrate a magnetothermal response. Similarly, the excitation and relaxation of electrons in IONPs under near-infrared light (NIR) enable photothermic-responsiveness. In combination, two findings nurtured an observed shape-memory effect when the samples are under actuation by these indirect stimuli, where a shape recovery ratio (>= 98%) and reversible strain (<= 7%) are recorded. Moreover, the catalytic role of IONPs aided transesterification in the covalent network, demonstrated by successful repeated cycles of shape reconfiguration of the samples. This work highlights the prospectives of multifunctional composite fillers in the exploration of bio-derived composite smart materials.

This is a short review of the recent progresses on Hofstadter butterfly in graphene, organized in the following. We first briefly introduce the Hofstadter butterfly, including the theoretic toy model of Bloch electrons in the magnetic field, the resulting Harper's equation and its solution, and realizations in non-graphene systems. Then, we discuss the ways to realize the fractal Hofstadter spectra in graphene, and introduce three types of graphene superlattice structure, including graphene-hBN, twisted graphene layers, nanofabricated graphene superlattice. In particular, details about the fractal Hofstadter spectrum in graphene will be focused and discussed in the graphene-hBN superlattice and the twisted bilayer graphene.

Nanowires can provide a large specific surface area and short carrier transport paths in photovoltaic and photoelectric detection devices, improving their photoelectric conversion efficiency and response speed. However, the ability to control the morphology and size of oxide nanowires is still a challenge. In this study, ZnO nanowire arrays were produced using superaligned carbon nanotube (SACNT) films as templates. The control of morphology and structure of oxide nanowires allowed them to grow orderly and be transferred onto any substrate. The as-prepared ZnO nanowires exhibited a unique hollow tubular network structure, which promoted the increase in specific surface area and carrier mobility. After 20 min of sputtering, the peak photoresponsivity of ZnO nanowires was 132% higher than that of directly deposited ZnO thin films. Moreover, it even exceeded the peak photoresponsivity of ZnO thin films at a sputtering time of 60 min, greatly reducing costs and increasing sputtering efficiency. This low-cost scalable method opens up prospects for the development and widespread application of high-performance ultraviolet (UV) photodetectors.

Two-dimensional (2D) materials enable vertical field effect transistors (VFETs), which provide an alternative path for scaling down the channels of transistors. The challenge is the short channel effect when the thickness of the 2D channel decreases to ∼10 nm. Here, we show that a VFET with an ultrashort channel can be accomplished by employing a semimetal carbon nanotube (CNT) as a 1D van der Waals (vdW) contact. The CNT-VFETs with 5-10 nm MoS2 channels exhibit high on/off ratios exceeding 105, low subthreshold swing values of 160-120 mV/dec, and high current densities over 104 A/cm2. Such a switch even works with an ∼ 3.4 nm thick channel. The excellent comprehensive performance can be ascribed to the reduced short channel effect as the sub-2 nm CNT contact has weaker electrostatic screening to the gate, a reduced Fermi level pinning effect, and a highly tunable barrier. The VFETs with 1D vdW contacts hold great promise for ultrascaled transistors and are prospective in future nanoelectronics and nano-optoelectronics.