Biaobing Jin

• Nanjing University

Achieving dynamic switching among absorption (A), reflection (R), and transmission (T) states is not only essential for advancing the understanding of light‐metasurface interactions but also holds significant potential for practical applications, such as selective electromagnetic shielding and smart windows. However, at terahertz and higher frequen...

The orbital Hall effect originating from light materials with weak spin‐orbit coupling, has attracted considerable interest in spintronic applications. Recent studies demonstrate that orbital currents can be generated from charge currents through the orbital Hall effect in ferromagnetic materials. However, the generation of orbital currents in anti...

As terahertz (THz) technology has been widely considered as a key candidate for future sixth‐generation wireless communication networks, THz modulators show profound significance in wireless communication, data storage, and imaging. In special, dynamic tuning of THz waves through 2D electron gas (2DEG) incorporated with a hybrid design of metasurfa...

Emerging reconfigurable metasurfaces offer various possibilities for programmatically manipulating electromagnetic waves across spatial, spectral, and temporal domains, showcasing great potential for enhancing terahertz applications. However, they are hindered by limited tunability, particularly evident in relatively small phase tuning over 270°, d...

Antiferromagnets are promising for nano-scale oscillator in a wide frequency range from gigahertz up to terahertz. Experimentally realizing antiferromagnetic moment oscillation via spin-orbit torque, however, remains elusive. Here, we demonstrate that the optical spin-orbit torque induced by circularly polarized laser can be used to drive free deca...

With the rapid development of terahertz-enabled devices, the study of miniaturized and integrated systems has attracted significant attention. We experimentally demonstrate an imaging-based pixelated metamaterial for detecting terahertz molecular fingerprints related to intermolecular vibrations and large-amplitude intramolecular modes, including c...

Ultrafast manipulation of optical resonance can establish the time-boundary effect in time-variant media leading to a new degree of freedom for coherent control of electromagnetic waves. Here, we demonstrate that a free-standing all dielectric Huygens metasurface of degenerate electric and magnetic resonances can prompt the broadband near-unity tra...

Since antiferromagnets (AFMs) have the potential to drive spintronic devices to higher speed and stability, generation, and transportation of terahertz (THz) spin currents in AFM/heavy metal (HM) structures have been extensively studied. However, effective methods to optimize the efficiency of THz spin current transmission at the interface are stil...

Emerging reconfigurable metasurfaces offer various possibilities in programmatically manipulating electromagnetic waves across spatial, spectral, and temporal domains, showcasing great potential for enhancing terahertz applications. However, they are hindered by limited tunability, particularly evident in relatively small phase tuning over 270o, du...

Néel spin-orbit torque allows a charge current pulse to efficiently manipulate the Néel vector in antiferromagnets, which offers a unique opportunity for ultrahigh density information storage with high speed. However, the reciprocal process of Néel spin-orbit torque, the generation of ultrafast charge current in antiferromagnets has not been demons...

The phenomenon of simultaneous degeneracy of eigenvalues and eigenstates in non-Hermitian systems, known as exceptional points (EPs), renders systems in the vicinity of EP highly sensitive to perturbations in the environment. Recently, research works on terahertz metasurfaces primarily focused on finding the degenerate eigenvalue using the transmis...

Nonlinear transport enabled by symmetry breaking in quantum materials has aroused considerable interest in condensed matter physics and interdisciplinary electronics. However, achieving a nonlinear optical response in centrosymmetric Dirac semimetals via defect engineering has remained a challenge. Here, we observe the helicity dependent terahertz...

Polarized vortex waves have attracted widespread attention in investigations of light–matter interactions and the augmentation of information capacity owing to their distinctive characteristics. Nevertheless, the reconfigurable generation of vector beams, especially at terahertz (THz) frequencies, remains challenging. In this study, a tunable THz p...

The metasurface platform with time-varying characteristics has emerged as a promising avenue for exploring exotic physics associated with Floquet materials and for designing photonic devices like linear frequency converters. However, the limited availability of materials with ultrafast responses hinders their applications in the terahertz range. He...

Recently, the growing interest in reconfigurable intelligent surface (RIS) technology has spurred extensive research on its utilization in the terahertz (THz) regime. The reconfiguration of the THz field empowered by the RIS holds great significance for various practical RIS-aided implementations at THz frequencies. In this study, we present a mult...

Symmetry breaking plays a crucial role in understanding the fundamental physics underlying numerous physical phenomena, including the electromagnetic response in resonators, giving rise to intriguing effects such as directional light scattering, supercavity lasing, and topologically protected states. This work demonstrates that adding a small fract...

Heterostructures between conventional superconductors and materials with different electronic ground states have emerged as a powerful method for exploring the exotic superconducting properties induced by the proximity effect. Here, we investigate Andreev transport through the interface between an s-wave superconductor Nb and a type-II Wely semimet...

Terahertz (THz) metasurfaces have emerged as the preferred material for active devices, with numerous potential applications. However, due to a lack of materials with an ultrafast response, functional devices with fascinating time-varying phenomena remain to be explored. In this study, we experimentally investigated a time-varying THz metasurface w...

Symmetry breaking plays a crucial role in understanding the fundamental physics underlying numerous physical phenomena, including the electromagnetic response in resonators, giving rise to intriguing effects such as directional light scattering, supercavity lasing, and topologically protected states. In this work, we demonstrate that adding a small...

Optical antireflection has been employed for a variety of applications in terahertz spectroscopy and detectors. However, current methods encounter challenges in terms of cost, bandwidth, structural complexity, and performance. In this study, a low-cost, broadband, and easily processed THz antireflection coating scheme based on the model of impedanc...

Dynamic manipulation of electromagnetic (EM) waves with multiple degrees of freedom plays an essential role in enhancing information processing. Currently, an enormous challenge is to realize directional terahertz (THz) holography. Recently, it was demonstrated that Janus metasurfaces could produce distinct responses to EM waves from two opposite i...

Terahertz (THz) filters with high transmission coefficient (T) in the passband and frequency selectivity are critical in numerous applications such as astronomical detection and next-generation wireless communication. Freestanding bandpass filters eliminate the Fabry–Pérot effect of substrate, thus providing a promising choice for cascaded THz meta...

We propose a simulation method for a multireflector terahertz imaging system. The description and verification of the method are based on an existing active bifocal terahertz imaging system at 0.22 THz. Using the phase conversion factor and angular spectrum propagation, the computation of the incident and received fields requires only a simple matr...

An important vision of modern magnetic research is to use antiferromagnets (AFMs) as controllable and active ultrafast components in spintronic devices. Hematite (α‐Fe2O3) is a promising model material in this respect because its pronounced Dzyaloshinskii‐Moriya interaction leads to the coexistence of antiferromagnetism and weak ferromagnetism. Her...

Subwavelength-sized metallic structures exhibit extraordinary responses to electromagnetic waves due to their geometry, generating surface plasmon polaritons (SPPs) at the metal–dielectric interface. The development and application of terahertz (THz) science, which is an emerging science, can be advanced by studying SPPs in the THz band. Because th...

Terahertz (THz) waves are extremely sensitive to water content and biological composition (proteins, genes, and metabolites), which are the key regulator of cancer development. Hence, the application of THz spectroscopy and imaging is promising in the field of biomedicine, especially in cancer diagnosis. Currently, the diagnosis of cancer patients...

Semiconductor Process Monitoring In article number 2201631, Zheng You, Xiaoguang Zhao, Lingyun Zhang, and co‐workers present terahertz barcodes consisting of electromagnetic metasurfaces as effective materials for semiconductor process control and monitoring applications. Once interrogated through a spectrometer, the response of the barcode reveals...

Active metasurfaces have attracted increased attention due to their capabilities in function switching and wavefront shaping. Here we develop a new paradigm for active control of metasurfaces via integrating a tunable and programmable spintronic terahertz emitter (STE). While compatible with almost all conventional materials for metasurfaces, the S...

Pancharatnam-Berry (PB) metasurfaces have demonstrated mighty capability to manipulate electromagnetic (EM) waves, and exhibited potential applications for devices with broadband and efficient functionality. However, it remains a challenge to simultaneously achieve broadband and efficient wavefront manipulation for terahertz (THz) components with s...

Reconfigurable intelligent surfaces (RISs) play an essential role in various applications, such as next-generation communication, uncrewed vehicles, and vital sign recognizers. However, in the terahertz (THz) region, the development of RISs is limited because of lacking tunable phase shifters and low-cost sensors. Here, we developed an integrated s...

Asymmetric manipulation of electromagnetic waves exhibits tremendous capabilities in the applications of encryption, ultrafast information processing, and communication. However, compact and broadband terahertz (THz) components for asymmetric applications are still scarce. Here, we demonstrate broadband, ultrathin, and efficient metasurface-based a...

An important vision of modern magnetic research is to use antiferromagnets as controllable and active ultrafast components in spintronic devices. Hematite is a promising model material in this respect because its pronounced Dzyaloshinskii-Moriya interaction leads to the coexistence of antiferromagnetism and weak ferromagnetism. Here, we use femtose...

The inverse spin Hall effect (ISHE) is one of accessible and reliable methods to detect spin current. The magnetization‐dependent inverse spin Hall effect has been observed in magnets, expanding the dimension for spin‐to‐charge conversion. However, antiferromagnetic Néel vector‐dependent ISHE is still elusive, which has been long time highly pursue...

The ultrafast modulation of terahertz (THz) waves is essential for numerous applications, such as high-rate wireless communication, nonreciprocal transmission, and linear frequency conversion. However, high-speed THz devices are rare due to the lack of materials that rapidly respond to external stimuli. Here, we demonstrate a dynamic THz metasurfac...

In this study, we describe the design, fabrication, and characterization of a cross-shaped structure reflective broadband THz polarization converter. The operating bandwidth of the proposed polarization converter was in the range of 0.8–1.6 THz. The polarization conversion rate (PCR) exceeded 85% in the frequency range of 1.07–1.35 THz and was as h...

Various kinds of metasurfaces have been proposed because they can be tailored to achieve the desired modulations on electromagnetic wave that do not occur in nature. Compared to conventional metamaterials, coding metasurfaces integrated with information science theory possess numerous distinctive advantages - simple design, time-saving and compatib...

A simple method for preparing superconducting NbN thin films on flexible dielectric substrates with controllable thickness was developed. The structure and surface characteristics and superconducting properties of the flexible film were studied by X-ray diffraction (XRD), atomic force microscopy (AFM) and physical property measurement system (PPMS)...

Spatial light modulators (SLM), capable of dynamically and spatially manipulating electromagnetic waves, have reshaped modern life in projection display and remote sensing. The progress of SLM will expedite next-generation communication and biomedical imaging in the terahertz (THz) range. However, most current THz SLMs are adapted from optical alte...

During the past decade, metasurfaces have provided a versatile platform for controlling the amplitude, phase, and polarization of electromagnetic waves, thus showing great potential for developing compact photonic devices. However, compact and broadband terahertz (THz) components are still scarce for high‐speed communication and spectroscopy analys...

We have designed and fabricated a superconducting hybrid NbTiN-Al kinetic inductance detector (KID) over a broad band centered at 4.3 THz. The detector sensitivity is characterized by changing the bath temperature in a dark environment. Both amplitude and phase readouts are performed. The measured electrical noise equivalent power for phase readout...

Programmable Memory Metamaterials In article number 2100472, Benwen Chen, Jingbo Wu, Biaobing Jin, and colleagues present a programmable terahertz metamaterial with memory function. Each pixel is electrically addressable by suppressing the thermal crosstalk, and modulation speed of 1 kHz is obtained. Its state enables being written, read, and erase...

Spatial light modulators (SLMs) exhibit a powerful capability of controlling electromagnetic waves. They are found to have numerous applications at terahertz (THz) frequencies, including wireless communication, digital holography, and compressive imaging. However, the development toward large‐scale, multi‐level, and multi‐functional THz SLM encount...

Blackbody radiation sources as a calibration source for terahertz radiometers have been widely used in recent decades with the development of terahertz detection technology in the fields of aerospace, astronomy and remote sensing. We developed a terahertz (THz) blackbody calibration source capable of working in the cryogenic environment and having...

In this paper, a real-time near-field high-resolution THz (Terahertz, THz) spectral imaging system is designed and built using optical rectification and wave-front tilting to generate strong-field terahertz signals and based on electro-optical detection. The system can switch between large beam THz imaging and tight-focusing THz imaging, which prov...

The increasing interest in antiferromagnetic electronics is driven by the vision of the operation in the terahertz regime and ultrahigh density memories. The use of a terahertz wave to scale up the writing speed to terahertz has been reported in the antiferromagnetic single layer CuMnAs with sublattice symmetry broken. Here, a reversible and reprod...

The tunability in Josephson junctions is foundational to the superconducting classical and quantum applications. Here, we demonstrate the local manipulation of supercurrent realized in a superconducting quantum interference device (SQUID) with two Nb/TiO x /Nb Josephson junctions that is biased at the TiO x layer. Our measurements indicate that the...

Metasurfaces employed for generating orbital angular momentum (OAM) beams have drawn tremendous interest since they can offer extensive applications ranging from quantum optics to information processing over the subwavelength scale. In this study, a flexible bilayer metasurface is proposed and experimentally verified in the terahertz (THz) region....

The Josephson plasmon resonance (JPR) offers a valuable probe to investigate the superconductivity in layered cuprate superconductors. However, the coupling between free space radiation and JPR in high‐temperature superconductor (HTS) film remains challenging because the excitation of JPR demands the c‐axis oriented electric field. The subwavelengt...

The gate-tunable Josephson junction, generally achieved in planar Josephson field-effect transistors (JoFETs), is a key element for the applications of superconducting devices. At present, the performance of these systems with planar JoFETs is often impeded by the large channel length, which, at best, lies in the range of tens of nanometers. In con...

We present an electrically tunable superconducting metamaterial capable of modulating terahertz (THz) waves. The device consists of two concentric ring resonators, which exhibits the electromagnetically induced transparency-like spectral response. A relatively high modulation depth of 86.8% and a group delay of 25.4 ps were achieved at the transmis...

We studied and improved the performance of a terahertz (THz) direct detector based on the superconducting NbN hot electron bolometer (HEB) integrated with microwave readout for imaging arrays and other applications. A 6 nm thick NbN microbridge at the feed point of a twin-slot antenna is embedded into a high-Q quarter-wavelength coplanar waveguide...

Dynamic terahertz (THz) beam steering is a promising technique for numerous applications, including communication, high-resolution imaging, and radar. However, advances in this technology are considerably limited by inadequate broadband and active phase shifters at THz frequencies. In this paper, we developed a type of VO2-based device capable of b...

Antiferromagnets (AFMs) have the potential to push spintronic devices from a static condition or gigahertz frequency range to the terahertz range for the sake of high-speed processing. However, the insensitivity of AFMs to magnetic fields makes the manipulation of spin currents difficult. The ultrafast generation of the spin current in ferromagnet/...

Spatial light modulators (SLMs) exhibited the powerful capability of controlling the electromagnetic wave. They have found numerous applications at terahertz (THz) frequencies, including wireless communication, digital holography, and compressive imaging. However, the development towards large-scale, multi-level and multi-functional THz SLM encount...

Coding metasurfaces have emerged as a promising venue for terahertz (THz) beam steering and beamforming. In this study, we designed a transmission metasurface with a complementary structure based on Babinet’s principle. The beam-steering capability of the coding metasurface is implemented by encoding “0” and “1” elements with different phase respon...

Chiral media exhibit optical activity, which manifests itself as differential retardation and attenuation of circularly polarized electromagnetic waves of opposite handedness. This effect can be described by different refractive indices for left‐ and right‐handed waves and yields a negative index in extreme cases. Here, active control of chirality,...

While the technology of microwave and infrared sources is quite mature and has been widely used in our daily life for decades, sources that can work well across the terahertz (THz) range are still lagging behind, which is often referred to as the “THz gap.” As one of the most pioneering THz setups, terahertz time-domain spectroscopy has been a vita...

We show the diffuse and specular reflection images of defective foams placed on iron plates, which are obtained by a bifocal active imaging system at 0.22 THz. Foam materials studied are extruded polystyrene boards and acetate copolymer boards with artificially embedded defects. In the field of view of approximately 50 × 90 cm <sup xmlns:mml="http:...

DOI:https://doi.org/10.1103/PhysRevApplied.14.059901

We demonstrate a high-efficiency visualized terahertz (THz) power meter based on the THz-photothermochromism of capsulized cholesteric liquid crystals (CCLCs) embedded in three-dimensional porous graphene (3DPG). The graphene is a broadband perfect absorber for THz radiation and transfers heat efficiently, and its black background is beneficial for...

We fabricate vertical Nb/TiOx/Nb Josephson junctions where the TiOx layer is mostly metallic but has a high-resistance interface with the top Nb electrode. Thus, the junctions are in essence of the superconductor–insulator–normal-metal–superconductor type. The TiOx layer extends beyond the junction area and allows one to send an in-plane current th...

Mirrors are widely used for redirection of electromagnetic waves in optical systems, making them arguably the most irreplaceable optical component. Metamaterial‐based chiral mirrors, composed of a 2D‐chiral planar metallic structure backed by a conventional mirror, reflect one circular polarization without changing its handedness, while absorbing t...

We experimentally studied a series of terahertz (THz) metamaterials with asymmetric resonator structures made from superconducting niobium nitride or gold films. Fano and toroidal dipole resonances are excited in superconducting metamaterials and their quality factors are higher in comparison with those of gold samples. Superconducting samples poss...

The coding metasurface integrated with tunable materials offers an attractive alternative to manipulate the THz beam dynamically. In this work, we demonstrate a THz programmable metasurface based on liquid crystal. The phase profile on the metasurface could be dynamically manipulated by switching the “0” and “1” states of each element. The programm...

Owing to appealing physical properties such as broad tunability in bandgaps and structural anisotropy, black phosphorus (BP) holds great potential in exploring novel electronic devices. However, it is extremely challenging to use BP to fabricate electronic devices, since it is prone to deteriorate in air. To address this challenge, we demonstrate a...

Relaxation oscillations related to terahertz (THz) power detection in superconducting niobium nitride hot electron bolometers (HEBs) have been studied using microwaves as a probe. The reflected microwave signal, which is related to the impedance changes of the HEB irradiated by an incident THz signal, can be used to characterize relaxation oscillat...

We describe a method for the active control of terahertz (THz) waves using vanadium dioxide (VO2)-embedded hybrid metamaterials (MMs). VO2 undergoes an insulator–metal phase transition at around 68 °C, causing its conductivity to change by five orders of magnitude. Our MM consists of a periodic array of two metallic structures connected with VO2 pa...

Photon-number-resolving (PNR) is an important functionality in many applications. The traditional SNSPDs operated with the conventional readout scheme do not have the PNR functionality. In this paper, we demonstrate a superconducting photon-number-resolving detector operating at the visible wavelength regime, based on the serial connection of six s...

In article number 1800070, Biaobing Jin, Wei Tan, and co‐workers design a bilayer metasurface which is composed of two different split‐ring resonators (SRRs) on the top and bottom surfaces of an ultrathin substrate with orthogonally oriented gaps, almost identical resonance frequencies and high loss‐contrast. It is designed to possess an exceptiona...

We report on a Stirling-cooled compact Bi2Sr2CaCu2O8+δ intrinsic Josephson-junction stack with very high critical current density and improved cooling, operating at bath temperatures Tb up to 86 K. The square stand-alone stack is embedded between two sapphire substrates. For bath temperatures between 27.8 and 86 K emission is observed at frequencie...