Lei Shao

Sun Yat-Sen University | SYSU · State Key Laboratory of Optoelectronic Materials and Technologies

Plasmonic materials have been extensively explored for surface-enhanced Raman scattering (SERS) due to their high tunability and excellent localized electric field enhancement. Most research for now has focused on noble metals, with limited investigation into corrosion-resistant materials for SERS effects. In this study, a photolithography process...

Diamond particles have many interesting properties and possible applications. However, producing diamond particles with well-defined shapes at scale is challenging because diamonds are chemically inert and extremely hard. Here, we show air oxidation, a routine method for purifying diamonds, can be used to precisely shape diamond particles at scale....

Multiple Fano resonances (mFRs) are arising as a promising optical platform to achieve precise sensing and detection. However, experimentally achieving mFRs by simple structures has remained challenging, which impedes the widespread applications of mFRs. Herein a simple structure composed of a single colloidal metal nanoparticle and a transition me...

Integrated 2-dimensional (2D) photonic devices such as monolayer waveguide has generated exceptional interest because of their ultimate thinness. In particular, they potentially permit stereo photonic architecture through bond-free van der Waals integration. However, little is known about the coupling and controlling of the single-atom guided wave...

The photoemission of surface plasmon decay-produced hot electrons is usually of very low efficiencies, hindering the practical utilization of such nonequilibrium charge carriers in harvesting photons with less energy than the semiconductor band gap for more efficient solar energy collection and photodetection. However, it has been demonstrated that...

The deposition of chiral nanoparticles (NPs) onto various substrates is crucial for the fabrication of high-density photonic devices. Understanding the interaction of chiral light and chiral NPs supported on substrates is essential for developing optical sensors and modulators. However, the chiroptical responses of plasmonic chiral NPs on substrate...

Transferring traditional plasmonic noble metal nanomaterials from the laboratory to industrial production has remained challenging due to the high price of noble metals. The development of cost-effective non-noble-metal alternatives with outstanding plasmonic properties has therefore become essential. Herein, we report on the gram-scale production...

Plasmonic waveguides have attracted tremendous interest due to efficiently confining photons on the subwavelength spatial scale to be beating the propagation diffraction limit. Transition metal molybdenum (Mo) exhibits outstanding properties in light trapping and electromagnetic field confining, making it potentially valuable in 1.55 μm plasmonic w...

Enriching the library of chiral plasmonic nanoparticles that can be chemically mass-produced will greatly facilitate the applications of chiral plasmonics in areas ranging from constructing optical metamaterials to sensing chiral molecules and activating immune cells. Here we report on a halide-assisted differential growth strategy that can direct...

Photothermal conversion, heat localization and water supply are the keys to achieving efficient solar‐driven interfacial evaporation. However, effective coupling between the three aspects at the air/liquid interface remains challenging. Herein, Au@Ag‐Pd trimetallic nanostructure/polystyrene (PS) microsphere Janus structures are designed as the sola...

Locally routing the exciton emissions in two-dimensional (2D) transition-metal dichalcogenides along different directions at the nanophotonic interface is of great interest in exploiting the promising 2D excitonic systems for functional nano-optical components. However, such control has remained elusive. Herein we report on a facile plasmonic appro...

The growing prevalence of counterfeit products worldwide poses serious threats to economic security and human health. Developing advanced anti-counterfeiting materials with physical unclonable functions offers an attractive defense strategy. Here, we report multimodal, dynamic and unclonable anti-counterfeiting labels based on diamond microparticle...

Chiral plasmonic nanostructures have attracted increasing attention because of their superchiral near‐fields as well as strong far‐field chiral optical response. Recently, the development of chemical synthesis methods enabled the large‐scale manufacturing of three‐dimensional colloidal chiral plasmonic nanocrystals. Further improving the chiral opt...

The growing prevalence of counterfeit products worldwide poses serious threats to economic security and human health. Developing advanced encryption materials with physical unclonable functions offers an attractive defense against counterfeiting. Here, we have successfully developed multimodal, dynamic and unclonable anti-counterfeiting labels base...

The increasing demand for compact and high-performance photonic devices drives the development of optical resonators with nanoscale sizes and ultrahigh quality factors. Fabry-Pérot (FP) resonators, the most widely employed optical resonators, can support ultrahigh quality factors in the simple structure, which is particularly attractive for applica...

Excitons in a transition-metal dichalcogenide (TMDC) monolayer can be modulated through strain with spatial and spectral control, which offers opportunities for constructing quantum emitters for applications in on-chip quantum communication and information processing. Strain-localized excitons in TMDC monolayers have so far mainly been observed und...

Moiré superlattices have led to observations of exotic emergent electronic properties such as superconductivity and strong correlated states in small-rotation-angle twisted bilayer graphene (tBLG)1,2. Recently, these findings have inspired the search for new properties in moiré plasmons. Although plasmon propagation in the tBLG basal plane has been...

Surface-enhanced Raman scattering (SERS) is a promising detection technique providing outstanding molecular fingerprint identification and high sensitivity of analytes. Developing sensitive and stable SERS substrates is highly desirable but remains a challenge. We herein report a wet-chemistry approach for the preparation of (Au nanorod core)@(Zr-b...

Structural Colors on Diamond Metasurfaces In article number 2100292, Ngai Wong, Zhiqin Chu, and co‐workers propose and demonstrate the concept of a low‐loss and high‐saturation color pixel design based on diamond metasurfaces. Moreover, a tensor completion‐based algorithm is introduced for the first time to assist the design of vivid colors, highly...

Bio-compatible Au nanoparticles exhibit great advantages in the application of biomedical research, such as bio-sensing, medical diagnosis, and cancer therapy. Bio-molecules can even be manipulated by laser tweezers with the optically trapped Au nanoparticles as handles. In this paper, optical scattering torque arising from coupled Au nanoparticles...

Artificial colors generated by light–matter interactions are widely achieved using metal or dielectric nanostructures. However, those systems are susceptible to reported issues like high optical loss and insufficient robustness, limiting their practical deployment. To address these limitations, the concept of a low‐loss and high‐saturation color pi...

Bio-compatible Au nanoparticles exhibit great advantages in the application of biomedical researches, such as bio-sensing, medical diagnosis, and cancer therapy. Bio-molecules can even be manipulated by laser tweezers with the optically trapped Au nanoparticles as handles. In this Letter, optical scattering torque arising from the coupled Au nanopa...

Benefiting from their low-loss light manipulation at subwavelength scales, optically resonant dielectric nanostructures have emerged as one of the most promising nanophotonic building blocks. Here, we theoretically conceive a dielectric nanocavity made of moderate-refractive-index gallium nitride and investigate the strong electromagnetic field con...

Plasmonic photocatalysis has received much attention owing to attractive plasmonic enhancement effects in improving the solar-to-chemical conversion efficiency. However, the photocatalytic efficiencies have remained low mainly due to the short carrier lifetime caused by the rapid recombination of plasmon-generated hot charge carriers. Although plas...

Light‐driven nanomotors have attracted much attention due to their potential applications. The movement of conventional nanomotors typically occurs in the solution phase, which limits their application fields. Utilizing visible light to drive nanomotors at the solid–liquid interface represents a grand challenge due to the large friction force betwe...

Plasmonic heterostructures composed of plasmonic metal nanocrystals (NCs) and semiconductors or metals have been attracting extensive attention due to their extraordinary properties and potential applications. Site-selective deposition of semiconductors or metals on anisotropic plasmonic metal NCs delivers more advantages than the core@shell nanost...

Light‐driven nanomotors have attracted much attention due to their potential applications. The movement of conventional nanomotors typically occurs in the solution phase, which limits their application fields. Utilizing visible light to drive nanomotors at the solid–liquid interface represents a grand challenge due to the large friction force betwe...

Plasmonic nanoparticles can concentrate electromagnetic fields at the nanoscale and function as a powerful intermediary to enhance light-matter interactions. They have been widely employed for solar energy harvesting, photocatalysis, medicine, sensing, imaging, spectroscopy, optics, and optoelectronics. In this Perspective, we provide a brief overv...

The reshaping of metal nanocrystals on substrates is usually realized by pulsed laser irradiation or ion-beam milling with complex procedures. In this work, we demonstrate a simple method for reshaping immobilized Au nanoplates through plasma treatment. Au nanoplates can be reshaped gradually with nearly periodic right pyramid arrays formed on the...

Plasmonic hotspots can enhance hot charge carrier generation, offering new opportunities for improving the photocatalytic activity. In this work, eight types of heteronanostructures are synthesized by selectively depositing catalytic metals at the different sites of highly asymmetric Au nanocups for the photocatalytic oxidation of o-phenylenediamin...

Plasmonic metal nanostructures generate vivid colors with high spatial resolution. Active control of plasmonic pixels by electrical means, which is compatible with integrated circuit technologies, is a promising technique for dynamic full color reflective display. However, the development of electrical plasmonic display is still limited by the diff...

Electronic valley in two-dimensional transition-metal dichalcogenides (2D TMDCs) offers a new degree of freedom for information storage and processing. The valley pseudospin can be optically encoded by photons with specific helicity, enabling the construction of electronic information devices with both high performance and low power consumption. Ro...

Chiral optical responses of bilayer metasurfaces made of twisted metallic nanorods are investigated in detail with focus on the collective effect due to lattice resonance (LR). Using an analytical approach based on the coupled dipole method (supported by full wave simulation), we find optical chirality is dramatically increased by the coupling betw...

To overcome the diffraction limit of electromagnetic waves, plasmonic and dielectric nanoantennas have been developed for manipulating the direction of light at nanoscale. The cover shows various types of nanoantennas made of different materials and in different architectures for directional light scattering and emission. They include V‐antennas, Y...

Directional light control at nanoscale shows great potential in applications such as holograms, optical neural networks, and ultracompact photonic circuits. Plasmonic nanostructures with designed geometrical shapes or complex architectures have been employed to manipulate light directionally. The interaction among the electric dipole and multipole...

Light manipulation has been widely employed in lighting, display, and energy storage, becoming an inseparable part of human lives. However, the conventional optical devices suffer from the diffraction limit of electromagnetic waves. To overcome the limitation, plasmonic and dielectric nanoantennas are introduced for the control of light direction a...

(Gold nanorod core)/(poly(3,4-ethylene-dioxythiophene) (PEDOT) shell) nanostructures are prepared by the surfactant-assisted oxidative polymerization of 3,4-ethylene-dioxythiophene on the surface of gold nanorods (NRs). The PEDOT shell exhibits distinct dielectric properties at doped and undoped states, which allows the manipulation of plasmonic re...

Optical anapoles are often realized with high‐refractive‐index dielectric nanoparticles or metallic metamaterials with complex geometries. In this work, anapole states and plasmon‐induced toroidal resonances are observed on a simple plasmonic configuration, which is made of individual Au nanoplates supported on Au films. The nanoplate and the film...

Valleytronics, based on the valley degree of freedom rather than charge, is a promising candidate for next-generation information devices beyond complementary metal–oxide–semiconductor (CMOS) technology1–4. Although many intriguing valleytronic properties have been explored based on excitonic injection or the non-local response of transverse curren...

Many organic molecules with various functional groups have been used to passivate the perovskite surface for improving the efficiency and stability of perovskite solar cell (PSCs). However, the intrinsic attributes of the passivation effect based on different chemical bonds are rarely studied. Here, we comparatively investigate the passivation effe...

Light exerts force or torque on objects through the momentum or angular momentum exchange between photons and the objects. For absorbing structures, light also induces a thermal gradient that can be used to power the object movement. The light‐driven mechanism, with the advantages of wireless, versatile modulation, and excellent spatial and tempora...

Graphene nanoribbons (GNRs) with atomically precise heterojunction interfaces are exploited as nanoscale light emitting devices with modulable emission frequencies. By connecting GNRs with different widths and lengths, topological boundary states can be formed and manipulated. Using first-principles-based atomistic simulations, we studied the lumin...

Two-dimensional (2D) materials, such as graphene, transition metal dichalcogenides, black phosphorus and hexagonal boron nitride, have been intensively investigated as building blocks for optoelectronic devices in the past few years. Very recently, significant efforts have been devoted to the improvement of the optoelectronic performances of 2D mat...

Plasmonic Fano resonance has attracted extensive attention for its many applications, including plasmonic sensing, electromagnetically induced transparency, light trapping and stopping, due to its narrow linewidth and asymmetric spectral shape. However, many metal nanostructures are designed with complex geometries to generate Fano resonance and fe...

We describe a route to the preparation of (metal yolk)/(porous ceria shell) nanostructures through the heterogeneous growth of ceria on porous metal nanoparticles followed by the calcination-induced shrinkage of the nanoparticles. The approach allows for the control of the ceria shell thickness, the metal yolk composition and size, which is difficu...

Plasmonic color generation from metal nanostructures has attracted intensive attention because of their excellence in achieving high spatial resolution, strong color contrast, and long‐term durability. The limited area of plasmonic patterns anchored on substrates and produced by current top‐down methods, however, severely restricts the advanced dev...

Hole-mask colloidal lithography (HCL) using self-assembled colloidal polymer nanospheres to create masks is a versatile technique to fabricate nanostructure arrays over wafer-scale areas. It is a powerful and cost-effective tool to produce plasmonic nanostructures. This review presents an overview of recent development of using the HCL technique to...

The interference between spectrally overlapping superradiant and subradiant plasmon resonances generates plasmonic Fano resonance, which allows for attractive applications such as electromagnetically induced transparency, light trapping, and refractometric sensing with high figures of merit. The active switching of plasmonic Fano resonance holds gr...

Photogenerated nonequilibrium hot carriers play a key role in graphene's intriguing optoelectronic properties. Compared to conventional photoexcitation, plasmon excitation can be engineered to enhance and control the generation and dynamics of hot carriers. Here, we report an unusual negative differential photoresponse of plasmon-induced "ultrahot"...

Quantum tunneling plays an important role in coupled plasmonic nanocavities with ultrasmall gap distances. It can lead to intriguing applications like plasmon mode excitation, hot carrier generation, and construction of ultra-compact electro-optic devices. Molecular junctions bridging plasmonic nanocavities can provide a tunneling channel at modera...

Antibody-antigen interactions are complex events central to immune response, in vivo and in vitro diagnostics, and development of therapeutic substances. We developed an ultrastable single-molecule localized surface plasmon resonance (LSPR) sensing platform optimized for studying antibody-antigen interaction kinetics over very long time scales. The...

Noble metal nanostructures are promising electrocatalysts with their performance determined by their size, shape, and architecture. This study reports the facile preparation of Au/(PdAg alloy) electrocatalysts with diverse architectures, including nanodumbbells, yolk/shell nanoframes, and yolk/shell nanoboxes, from Au nanorod core/Ag shell bimetall...

Colloidal metal nanocrystals exhibit distinct plasmonic resonances that can greatly enhance optical forces and torques. This article highlights the recent application of such particles as light-driven rotary motors at the nanoscale. By using laser tweezers, it is possible to achieve unprecedented rotation performance in solution, providing a variet...

Brownian microparticles diffusing in optical potential energy landscapes constitute a generic testbed for nonequilibrium statistical thermodynamics and has been used to emulate a wide variety of physical systems, ranging from Josephson junctions to Stirling engines. Here we demonstrate that it is possible to scale down this approach to nanometric l...

Brownian microparticles diffusing in optical potential energy landscapes constitute a generic testbed for nonequilibrium statistical thermodynamics and has been used to emulate a wide variety of physical systems, ranging from Josephson junctions to Stirling engines. Here we demonstrate that it is possible to scale down this approach to nanometric l...

Gold nanoparticles offer a unique possibility for contact-free bioanalysis and actuation with high spatial resolution that increases their potential for bio-applications such as affinity based biosensing, drug delivery and cancer treatment. Here we demonstrate an ultra-sensitive optomechanical method for probing and releasing DNA cargo from individ...

Plasmonic structures exhibit promising applications in high-resolution and durable color generation. Research on advanced hybrid plasmonic materials that allow dynamically reconfigurable color control has developed rapidly in recent years. Some of these results may give rise to practically applicable reflective displays in living colors with high p...

Plasmonic gold nanorods are prime candidates for a variety of biomedical, spectroscopy, data storage and sensing applications. It was recently shown that gold nanorods optically trapped by a focused circularly polarized laser beam can function as extremely efficient nanoscopic rotary motors. The system holds promise for applications ranging from na...

Gold nanorods can be optically trapped in aqueous solution and forced to rotate at kilohertz rates by circularly polarized laser light. This enables detailed investigations of local environmental parameters and processes, such as medium viscosity and nanoparticle–molecule reactions. Future applications may include nanoactuation and single-cell anal...

High-refractive-index silicon nanoresonators are promising low-loss alternatives to plasmonic particles in CMOS-compatible nanophotonics applications. However, complex 3D particle morphologies are challenging to realize in practice, thus limiting the range of achievable optical functionalities. Using 3D film structuring and a novel gradient mask tr...

Gold nanocrystals can be used in various biomedical applications due to their excellent chemical and physical properties. They also exhibit promising potentials in further clinical practices. In particular, in contrast with small molecules and bulk materials, Au nanocrystals exhibit fascinating plasmonic properties, which allow them to possess extr...

Ultrathin plasmonic metasurfaces create bright colors when illuminated by white light. On page 9956, A. B. Dahlin and co-workers show that by growing a conductive polymer on the nanostructures, they can be electrically switched between a “color on” and a “color off” state. This opens up the way for new types of low-power flexible electronic paper d...