Optical force, coming from momentum exchange during light-matter interactions, has been widely utilized to manipulate microscopic objects, though mostly in vacuum or in liquids. By contrast, due to the light-induced thermal effect, photophoretic force provides an alternative and effective way to transport light-absorbing particles in ambient gases. However, in most cases these forces work independently. Here, by employing the synergy of optical force and photophoretic force, we propose and experimentally demonstrate a configuration which can drive a micron-size metallic plate moving back and forth on a tapered fiber with supercontinuum light in ambient air. Optical pulling and oscillation of the metallic plate are experimentally realized. The results might open exhilarating possibilities in applications of optical driving and energy conversion.

Leaky plasmon modes (LPMs) in metal nanowires (NWs), which combine the physical characteristic of both “plasmonics” and “leaky radiation”, present distinguished performances in terms of guiding and radiating light. In contrast to traditional light‐guiding in metal NWs with one single LPM, multiple LPMs are crucial for advanced uses such as augmenting data transmission channels, enhancing sensing performance, manipulating polarization and converting mode. Here, we demonstrate experimentally the control over multiple LPMs in pentagonal silver NWs. By combining far‐field real‐space imaging and leakage radiation microscopy, the three typical LPMs with fields mainly concentrating in corners surrounded by air are specifically identified. By manipulating excitation wavelengths and NW diameters, the number of the excited LPMs can be controlled. These findings reveal the physics of LPMs in silver NWs, thereby paving the way towards applying the high‐order leaky modes in silver NWs for photonic integrated circuits, nanoscale confinement, plasmonic sensing, QD‐nanowire coupling, etc.

Surface plasmon polaritons (SPPs) propagating at metal nanostructures play an important role in breaking the diffraction limit. Chemically synthesized single-crystalline metal nanoplates with atomically flat surfaces provide favorable features compared with traditional polycrystalline metal films. The excitation and propagation of leaky SPPs on micrometer sized (10–20 μm) and thin (30 nm) gold nanoplates are investigated utilizing leakage radiation microscopy. By varying polarization and excitation positions of incident light on apexes of nanoplates, wave-vector (including propagation constant and propagation direction) distributions of leaky SPPs in Fourier planes can be controlled, indicating tunable SPP propagation. These results hold promise for potential development of chemically synthesized single-crystalline metal nanoplates as plasmonic platforms in future applications.

Nanowelding of nanomaterials opens up an emerging set of applications in transparent conductors, thin-film solar cells, nanocatalysis, cancer therapy, and nanoscale patterning. Single point nanowelding (SPNW) is highly demanded for building complex nanostructures. In this letter, the precise control of SPNW of silver nanowires is explored in depth, where the nanowelding is laser-induced through the plasmonic resonance enhanced photothermal effect. It is shown that the illumination position is a critical factor for the nanowelding process. As an example of performance enhancement, output at wire end can be increased by 65% after welding for a plasmonic nanocoupler. Thus, single point nanowelding technique shows great potentials for high-performance electronic and photonic devices based on nanowires, such as nanoelectronic circuits and plasmonic nanodevices.

Nanojoining (including nanowelding, nanosoldering, etc.) of metal nanomaterials offers the opportunity of constructing complex structures and advanced functional devices at the nanoscale. In comparison with nanowelding, nanosoldering does not involve the melting of base metal and shows considerable mechanical strength and good thermal and electrical conductivity. Here, an optically controlled local nanosoldering technique, which ensures the nanostructures to be bonded while their original structural integrity is retained, is proposed and demonstrated. Typical elemental devices (V-shaped, T-shaped, and X-shaped nanostructures) are formed with this nanosoldering technique. The conductivity of one V-shaped junction is enhanced by 500 times after nanosoldering. This facile nanosoldering technique provides an avenue to locally manipulate light, charge, heat, and mass transport at the nanoscale and is thereby expected to benefit the development of nanophotonics and nanoelectronics.

to develop an adequate method to combine them together and understand its charge transport mechanisms.Recent advancements in the field of welding of NWs research indicate its potential capabilities in fabrication and repairing nanoelectronics, [16][17][18][19] nanophotonics, [20] nanomedicine, [21] and nanoelectromechanical systems. [22] There are reports of successful nanowelding following various techniques, including thermal annealing, [23] optical welding, [24][25][26][27][28] capillarity-driven welding, [29] chemical welding, [30] spot welding, [31] stretchinduced cold-welding, [32][33][34] and welding by Joule heating. [35,36] Although much progress has been achieved in this field, there remains many cumbersome issues, such as necessitating complicated and expensive experimental setup, use of chemicals which can contaminate the system, and lack of robustness corresponding to mechanical strength and electrical connectivity, yet to be addressed. Furthermore, the joining of semiconductor and metal NWs remains a challenging issue for miniaturization and integration of next generation nanodevices as the melting points of these two different types of materials are different.In this article, we present a relatively simple technique to achieve adequate welding of ZnO NW with Ag NW and also both type of NWs with Au electrode toward realizing heterojunction-based electronic nanodevices. The effects of local heat generation in closely spaced semiconductor and metal nanostructures due to strong optical interactions have been utilized for melting and eventually welding these nanostructures. Following this technique, four different electronic devices (two devices consisting of one Schottky and two ohmic junctions, one device with two back-to-back Schottky junctions, and another one with three ohmic contacts) have been fabricated. The devices with one Schottky and two ohmic junctions have been fabricated following two different approaches for two different orientations of the ZnO (top/bottom) and Ag (bottom/top) NWs. Although the temperature difference between the melting points of ZnO and Ag NWs is about 1000 K, it has been demonstrated that the melting points of both NWs are reached simultaneously when ZnO NW in on top of Ag NW, which results in superior quality of welding. Thereafter, toward understanding the transport mechanisms of all these devices, the obtained currentvoltage (I-V) characteristic curves are analyzed in detail. This photothermal nanowelding technique paves the path for realizing heterostructure-based 1D electronic nanodevices.An improvised and comparatively inexpensive method for welding semiconductors and metal nanowires (NWs) utilizing a plasmon-enhanced photothermal effect is presented in this article. Different types of heterojunction-based (single Schottky junction and back-to-back Schottky junctions) electronic nanodevices are fabricated by welding various combinations of silver and ZnO NWs on two gold electrodes using continuous wave laser (λ = 532 nm) shots. It is inferred from the current-vo...

Healing defects of metallic structures is an essential procedure for manufacturing and maintaining integrated devices. Current nanocomposite-assisted microhealing methodologies are inadequate for nanoscopic applications because of their concomitant contamination and limited operation accuracy. In this paper, we propose an optically controllable targeted nanohealing technique by utilizing the plasmonic-enhanced photothermal effect. The healing of nanogaps between two silver nanowires (NWs) is achieved by increasing the incident laser power in steps. Partial connection of NWs can be readily obtained using this technique, while near-perfect connection of NWs with the same crystal orientations is obtained only when the lattices on the two opposing facets are matched after recrystallization. This non-contaminating nanohealing technique not only provides deeper insight into the heat/mass transfer assisted by plasmonic photothermal conversion in the nanoscale but also suggests avenues for recovering mechanical, electronic, and photonic properties of defected metallic nanodevices.

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