Abstract Tunable band-stop filters based on graphene with periodically modulated chemical potentials are proposed. Periodic can be considered as a plasmonic crystal. Its energy band diagram is analyzed, which clearly shows blue shift of the forbidden increasing potential. Structural design and optimization performed by an effective-index-based transfer matrix method, confirmed numerical simulations. The center frequency filter tuned in range from 37 to 53 THz electrical tunability graphene,...

General actively tunable near-field plasmon-induced transparency (PIT) systems based on couplings between localized plasmon resonances of graphene nanostructures not only suffer from interantenna separations smaller than 20 nm, but also lack switchable effect about the window. Here, performance an active PIT system grating-sheet with coupling distance more 100 nm is investigated in mid-infrared. The window spectrum analyzed objectively and proved to be likely stemmed Aulter-Townes splitting....

Osmotic conditions play an important role in the cell properties of human red blood cells (RBCs), which are crucial for pathological analysis some diseases such as malaria. Over past decades, numerous efforts have mainly focused on study RBC biomechanical that arise from unique deformability erythrocytes. Here, we demonstrate nonlinear optical effects RBCs suspended different osmotic solutions. Specifically, observe self-trapping and scattering-resistant propagation a laser beam through...

We propose a simple and cost-effect method, current-stimulus dielectric breakdown, to manipulate the 3D shapes of nanochannels in 20-nm-thick SiNx membranes. Besides precise control nanopore size, cone orientation can be determined by pulse polarity. The angle nanopores systematically tuned simply changing stimulus waveform, allowing gradual shape from conical obconical. After they are formed, these further certain range adjusting widening pulse. Such size controllable abiotic construct...

Optical trapping is important in assessing the deformability of red blood cells (RBCs), providing quick, noncontact force measurement liquid medium with piconewton resolution. Traditional techniques, though, can involve complicated processes or cause photodamage. This study employs ``tug-of-war'' (TOW) optical tweezers object-adapted potentials, to simply and stably trap, stretch, squeeze a single RBC under different osmotic conditions, thus enabling assessment deformability. The large...

Unidirectionally propagated electromagnetic waves are rare in nature but heavily sought after due to their potential applications backscatter-free optical information processing setups. It was theoretically shown that the distinct bulk band topologies of a gyrotropic metal and an isotropic can enable topologically protected unidirectional surface plasmon polaritons (SPPs) at interface. Here, we experimentally identify such interfacial modes terahertz frequencies. Launching SPPs via tailored...

Abruptly autofocusing beams were proposed and tested for a variety of applications such as optical manipulation, yet their trapping performance associated with the forces trap stiffness remains largely unexplored. In this work, we design demonstrate specially modulated beams. We theoretically experimentally show improved properties capabilities compared to unmodulated counterparts. particular, an beam tailored Bessel function exhibits shorter focal length much stronger peak intensity than...

Graphene plasmons provide great opportunities in light–matter interactions benefiting from the extreme confinement and electrical tunability. Structured graphene cavities possess enhanced confinements 3D steerable plasmon resonances, potential applications for sensing emission control at nanoscale. Besides boundaries obtained by mask lithography, defects engineered ion beams have shown efficient reflections. In this paper, near‐field responses of structured achieved beam direct‐writing are...

In the past decade, development of artificial materials exhibiting novel optical properties has become a major scientific endeavor. One particularly interesting system is synthetic soft matter, which plays central role in numerous fields ranging from life sciences, chemistry to condensed matter and biophysics. this paper, we review briefly force-induced nonlinearities colloidal suspensions, can give rise nonlinear self-trapping light for enhanced propagation through otherwise highly...

The spatial switching of mid-infrared light near-fields is proposed in coupled graphene heterogeneous ribbon pairs. By using the plasmon modes pairs, electric near-field enhancement can be spatially controlled ribbons as tuning external bias voltage difference. More specifically, due to symmetry breaking, anti-symmetrically dipolar plasmons exist except for symmetrically homogeneous Moreover, gap distance one key parameters near-fields, strong coupling means efficient control near-fields.

The electrical, optical, mechanical and thermal properties of graphene can be significantly altered by defects, thus engineering the defects in is promising for applications functionalized materials nanoscale devices. Here propagations surface plasmon waves near defect boundaries created ion beams are studied. Specifically, reflections observed induced first time, which implies that ion-irradiation act as efficient scattering centers plasmonic waves, just like native grain boundaries....

We experimentally demonstrate self-trapping of light, as a result plasmonic resonant optical nonlinearity, in both aqueous and organic (toluene) suspensions gold nanorods. The threshold power for soliton formation is greatly reduced toluene opposed to suspensions. It well known that the gradient forces are optimized at off-resonance wavelengths which suspended particles typically exhibit strong positive (or negative) polarizability. However, surprisingly, we tune wavelength beam from...

An optically bistable device based on a Bragg grating resonator with nonlinear medium in metal-insulator-metal waveguides is proposed. Its properties are numerically investigated by finite-difference time-domain method and further qualitatively analyzed adopting Airy equation. Cavities different Q factors compared respect to bi-stability. small factor lead high transmission narrow hysteresis loop. The response time of such cavities found be the sub-picosecond region. Our nano-scale switching...

Spontaneous emission control of an optical emitter is critical for many applications, such as in the fields sensing, integrated photonics and quantum optics. Integrating emitters with a mechanical system can provide avenue strain sensors well. Here, dynamic spontaneous modification coupled to graphene by uniaxial demonstrated. Our results show that rate be controlled tuning graphene, which depends on polarized orientation emitter. More specifically, decay enhanced several times if...

The excitation of the higher-order multipole localized surface plasmon resonance (LSPR) modes in sub-10 nm-gap plasmonic structure is desired many enhancement applications. However, unfortunately, are either hard to be excited by light or make a very small contribution electromagnetic enhancement, generally. In this paper, we demonstrate that tunable longitudinal LSPR can large-area metal structures based on mature PS@Au core-halfshell ordered array nanostructure experiment and numerical...

We propose a method for generation of tunable three-dimensional (3D) helical lattices with varying helix pitch. In order to change only the lattice pitch, periodically phase along propagation direction is added central beam - one interference beams construction. The periodicity determines which can be reconfigured at ease. Furthermore, structure an interface (domain wall) also achieved by changing lateral beams, leading opposite rotating (helicity) on different sides interface. When Gaussian...

Plasmonic Tamm states configuration is proposed for field enhancement in an insulator–metal–insulator (IMI) Bragg reflector by periodic modulation of the dielectrics surrounding metal core. Finite-difference time-domain simulation carried out structure optimization and dispersion relation plasmonic states. In metal–Bragg interface, 2 orders magnitude electromagnetic intensity 4 decay rate are obtained. Besides enhancement, there two that related to even odd modes IMI waveguide. The show...

We present a bistable device consisting of Bragg grating resonator with Kerr medium sandwiched between two dielectric slab waveguides. The is situated in nanometer-scaled metal?insulator?metal plasmonic waveguide. Due to the dimensional confinement from waveguide nanoscaled waveguide, electric fields are enhanced greatly, which will further reduce threshold value. Moreover, semi-analytic method, based on impedance theory and transfer matrix developed study transmission reflection spectra as...

Plasmon nanoresonators in graphene have many applications biosensing, photodetectors and modulators. As a result, an efficient precise patterning technique for is required. Helium ion lithography (HIL) emerges as promising tool direct writing fabrication because it owns improved precision compared to electron beam conventional gallium focused technique. In this paper, utilizing HIL, set of triangles are patterned excellent plasmon response detected. Particularly, the evolution breathing mode...

Strong coupling originating from excitons of quantum dots and plasmons in nanocavities can be realized at room temperature due to the large electromagnetic field enhancement plasmons, offering building blocks for information systems, ultralow-power switches lasers. However, most current strong effects were by interaction between far-field light excited bright plasmon modes visible range. Beyond that, there is still a lack direct imaging polariton nanoscale. In this work, using...

The interactions between light and plasmonic charge oscillations in conducting materials are important venues for realizing nanoscale manipulations. Conventional metal-based devices lack tunability due to the fixed material permittivities. Here, we show that reconfigurable functionalities can be achieved using spatially controlled phase transitions strongly correlated oxide films. experimental results discussed here enabled by a recently developed scanning probe-based technique allows...

Controlled orientation and alignment of rod‐shaped plasmonic nanoparticles are great interest for many applications. Herein, it is demonstrated that the nonlinear optical response gold nanorod suspensions dynamically controlled by electric field‐induced orientation. Merely switching incident light polarization, longitudinal transverse surface plasmon resonance (SPR) absorption peaks modulated with opposite trends, resulting nonlinearity revealed from self‐trapping resonant solitons....

Aluminum (Al) has prominent material and plasmonic properties in the ultraviolet (UV) spectral range. However, large losses of plasmon antennas with multicrystal Al is bottleneck for applications. Here, single-crystal nanostructures are compared. In platform bulk Al, spatially spectrally resolved cathodoluminescence (CL) spectroscopy used to excite image modes I-shaped cross-shaped nanoridge antennas. The evolution coupling at nanoscale clearly observed these Plasmon can be exactly...

Using cathodoluminescence, the plasmonic modes of open triangle cavities patterned in single-crystal bulk aluminum are explored deep subwavelengths from UV to visible, showing large <italic>Q</italic> factors.