Near-infrared Wavelength Range Research Articles

Polymer-Peptide Modified Gold Nanorods to Improve Cell Conjugation and Cell labelling for Stem Cells Photoacoustic Imaging.

The use of gold nanorods (GNRs) as a contrast agent in bioimaging and cell tracking has numerous advantages, primarily due to the unique optical properties of gold nanorods which allow for the use of infrared regions when imaging. Owing to their unique geometry, Au NRs exhibit surface plasmon modes in the near-infrared wavelength range, which is ideal for carrying out optical measurements in biological fluids and tissue. Gold nanorod functionalization is essential, since the Cetyltrimethyl ammonium bromide CTAB gold nanorods are toxic, and for further in vitro and in vivo experiments the nanorods should be functionalized to become optically stable and biocompatible. In the present study, gold nanorods with an longitudinal surface plasmon resonance (LSPR) position around 800 nm were synthesized in order to be used for photoacoustic imaging applications for stem cell tracking. The gold nanorods were functionalized using both thiolated poly (ethylene glycol) (PEG) to stabilize the gold nanorods surface and a CALNN–TAT peptide sequence. Both ligands were attached to the gold nanorods through an Au–sulfur bond. CALNN–TAT is known as a cell penetrating peptide which ensures endocytosis of the gold nanorods inside the mesenchymal stem cells of mice (MSCD1). Surface modifications of gold nanorods were achieved using optical spectroscopy (UV–VIS), electron microscopy (TEM), zeta-potential, and FTIR. Gold nanorods were incubated in MSCD1 in order to achieve a cellular uptake that was characterized by a transmission electron microscope (TEM). For photoacoustic imaging, Multi-Spectral Optoacoustic Tomography (MSOT) was used. The results demonstrated good cellular uptake for PEG–CALNN–TAT GNRs and the successful use of modified gold nanorods as both a contrast agent in photoacoustic imaging and as a novel tracking bioimaging technique.

Germanium Nanosheets with Dirac Characteristics as a Saturable Absorber for Ultrafast Pulse Generation.

Bulk germanium as a group-IV photonic material has been widely studied due to its relatively large refractive index and broadband and low propagation loss from near-infrared to mid-infrared. Inspired by the research of graphene, the 2D counterpart of bulk germanium, germanene, has been discovered and the characteristics of Dirac electrons have been observed. However, the optical properties of germanene still remain elusive. In this work, several layers of germanene are prepared with Dirac electronic characteristics and its morphology, band structure, carrier dynamics, and nonlinear optical properties are systematically investigated. It is surprisingly found that germanene has a fast carrier-relaxation time comparable to that of graphene and a relatively large nonlinear absorption coefficient, which is an order of magnitude higher than that of graphene in the near-infrared wavelength range. Based on these findings, germanene is applied as a new saturable absorber to construct an ultrafast mode-locked laser, and sub-picosecond pulse generation in the telecommunication band is realized. The results suggest that germanene can be used as a new type of group-IV material for various nonlinear optics and photonic applications.

Theory of exciton thermal radiation in semiconducting single-walled carbon nanotubes.

Spectral control of thermal radiation is an essential strategy for highly efficient and functional utilization of thermal radiation energy. Among the various proposed methods, quantum confinement in low-dimensional materials is promising because of its inherent ability to emit narrowband thermal radiation. Here, we theoretically investigate thermal radiation from one-dimensional (1D) semiconductors characterized by the strong quantum correlation effect due to the Coulomb interaction. We derive a simple and useful formula for the emissivity, which is then used to calculate the thermal radiation spectrum of semiconducting single-walled carbon nanotubes as a representative of 1D semiconductors. The calculations show that the exciton state, which is an electron-hole pair mutually bound by the Coulomb interaction, causes enhancement of the radiation spectrum peak and significant narrowing of its linewidth in the near-infrared wavelength range. The theory developed here will be a firm foundation for exciton thermal radiation in 1D semiconductors, which is expected to lead to new energy harvesting technologies.

A Near-Infrared Organic Fluorescent Probe for Broad Applications for Blood Vessels Imaging by High-Throughput Screening via 3D-Blood Vessel Models.

Blood vessels are present in all of the organs, reflecting their importance for oxygen and nutrient delivery to the cells. Until now, no organic fluorophore has been reported for the live imaging of endothelium although the layer is the key to blood vessel functions. Here, the discovery of a blood vessel organic probe at near-infrared (NIR) wavelength range (BV-NIR) through an engineered blood capillary-based screening system, which is a more physiological model than a conventional cell culture condition, is reported. This selected Cy5 based probe shows the highest specific adsorption property out of 240 candidates on the endothelium and is equivalent to an anti-CD31 antibody in terms of intensity. The BV-NIR probe indicating strong and stable in vitro, ex vivo, and in vivo imaging of the endothelium even after histological immunostaining processes shows potential as a convenient tool for live imaging as well as for covisualization with a specific antibody.

Two-Dimensional Bi2Sr2CaCu2O8+δ Nanosheets for Ultrafast Photonics and Optoelectronics.

Two-dimensional (2D) Bi2Sr2CaCu2O8+δ (BSCCO) is a emerming class of 2D materials with high-temperature superconductivity for which their electronic transport properties have been intensively studied. However, the optical properties, especially nonlinear optical response and the photonic and optoelectronic applications of normal state 2D Bi2Sr2CaCu2O8+δ (Bi-2212), have been largely unexplored. Here, the linear and nonlinear optical properties of mechanically exfoliated Bi-2212 thin flakes are systematically investigated. 2D Bi-2212 shows a profound plasmon absorption in near-infrared wavelength range with ultrafast carrier dynamics as well as tunable nonlinear absorption depending on the thickness. We demonstrated that 2D Bi-2212 can be applied not only as an effective mode-locker for ultrashort pulse generation but also as an active medium for infrared light detection due to its plasmon absorption. Our results may trigger follow up studies on the optical properties of 2D BSCCO and demonstrate potential opportunities for photonic and optoelectronic applications.

Numerical investigation of metasurface narrowband perfect absorber and a plasmonic sensor for a near-infrared wavelength range

Herein, we have presented a computation study of a metasurface (MS) narrowband perfect absorber performed utilizing the three-dimensional finite element method. In the first part of the paper, the periodic sequence of silicon meta-atoms (MAs) is positioned on a ∼100 nm gold thin-film. The gold thin-film obstructs a broadband light at normal incidence, and silicon MAs are utilized to stimulate the surface plasmon by scattering light through it. The highest absorption of 96% is procured at 930.26 nm in the air medium which can be further enhanced by using a layered structure of MAs deposited on gold. The MAs are composed of Si/SiO2/Si with an optimized layers height. Consequently, the perfect impedance matching of the electric and magnetic dipoles takes place providing a 99% of absorption insensitive to the incidence angle of light and almost negligible reflection at a resonating wavelength of 889.4 nm. This feature allows us to utilize this device as a plasmonic sensor. That is why, in the second part of the paper, the proposed device design is studied for the detection of the refractive index of the surrounding medium. The sensitivity and figure of merits of the MS device are in the range of 460–492 nm RIU−1 and 76.7–82 RIU−1, respectively. We claim that the anticipated MS element can be employed in solar photovoltaic and biomedical sensing purposes.

Supercontinuum Generation in High Order Waveguide Mode with near-Visible Pumping Using Aluminum Nitride Waveguides

Optical sources emitting in the ultraviolet (UV) to near-infrared wavelength range are an enabling tools for a wide variety of applications. To achieve broadband coherent generation within visible ...

Theoretical Analysis of AlAs₀.₅₆Sb₀.₄₄ Single Photon Avalanche Diodes With High Breakdown Probability

Single photon avalanche diodes (SPADs) are key enabling technologies for a wide range of applications in the near-infrared wavelength range. Recently, AlAs <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0.56</sub> Sb <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0.44</sub> (hereafter AlAsSb) lattice-matched to InP has been demonstrated for extremely low excess noise avalanche photodiodes (APDs) due to its large disparity between electron and hole ionization coefficients ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\alpha $ </tex-math></inline-formula> and <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\beta $ </tex-math></inline-formula> respectively). The <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\alpha /\beta $ </tex-math></inline-formula> ratio also plays a role in Geiger mode operation as it affects the avalanche breakdown probability and hence detection efficiency. In this work, we theoretically investigate the performance of AlAsSb based SPADs. The probability of breakdown for electron-initiated Geiger mode operation increases more sharply with multiplication region width due to progressively more dissimilar ionization coefficients. In comparison with other common avalanche materials, such as InAlAs, InP and Si, our result also suggests that SPADs based on AlAsSb have a sharper breakdown probability than the other three materials under similar low overbias ratio. The calculated breakdown probability of 0.81 in AlAsSb is 0.18 and 0.28 higher than that of InAlAs/Si and InP respectively at 5% overbias ratio and with avalanche region width of 1500 nm.

Bio-inspired butterfly core-shaped photonic crystal fiber-based refractive index sensor

Light controllability, design flexibility, and non-linearity features of photonic crystal fiber (PCF) based surface plasmon resonance (SPR) sensor enable high sensitivity in the field of biosensing. Here, bio-inspired butterfly-core shaped microstructure fiber-based plasmonic sensor is proposed where circular air-holes are arranged to enhance the sensing performance. Butterfly shaped core is designed to confine the incident light into the core by preventing light scattering through the cladding and helps to excite surface electron of plasmonic metal layer. Chemically stable plasmonic material gold is used to produce the SPR phenomenon. The analyte detection layer and the plasmon layer are located externally on the PCF surface to make the detection process more feasible. The sensor performance is studied based on the finite element method (FEM), and the structural parameters are tuned to obtain maximum sensor performance. This modified core-based sensor exhibits the maximum wavelength sensitivity (WS) of 56,000 nm/RIU and the amplitude sensitivity (AS) of 1,584 RIU-1 for the x-polarized mode. It also shows an improved sensor resolution (SR) of 1.8 ×10−6 RIU, along with a decent figure of merit (FOM) of 691 RIU-1. Moreover, this sensor can detect analyte refractive indexes (RI) within a broad RI range of 1.33 to 1.42 in the visible to near-infrared wavelength range (450–2100 nm). Finally, the proposed sensor may have possible application to detect organic chemicals, food quality, and diseases with high accuracy due to outstanding sensitivity and linearity.

Vinylene π-bridge: A simple building block for ultra-narrow bandgap nonfullerene acceptors enable 14.2% efficiency in binary organic solar cells

Ultra-narrow bandgap (ultra-NBG) nonfullerene acceptors (NFAs) are essential for advancing the development of organic solar cells (OSCs). In this paper, a synergistic strategy of π-bridge and asymmetric engineering is applied to state-of-the-art Y-series NFAs, and it achieves ultra-NBG NFAs for efficient OSCs. Introduction of vinylene π bridges into the Y-series NFA in a symmetric pattern, resulting in a molecule, BTP-2V-2F, which exhibits moderate power conversion efficiency (PCE) of 11%, despite extending absorption near-infrared wavelength range. Through tailoring the number of vinylene π-bridges in the asymmetric backbone, another molecule, BTP-1V-2F, results which not only shows near-infrared absorption improvement, but also low-lying frontier molecular orbital levels. Benefiting from the maintained photocurrent along with the higher open-circuit voltage and the fill factor, a superior efficiency of 14.24% is achieved, which is one of the highest values for binary single-junction OSCs based on ultra-NBG NFA with a bandgap below 1.29 eV. The results demonstrate that the effectiveness of the vinylene π-bridge and asymmetric engineering on designing ultra-NBG NFAs, which aids the avenue toward developing more efficient ultra-NBG-based OSCs.

The near-infrared observations at the Tower Solar Telescope TST-2 of the Crimean Astrophysical Observatory

Abstract Observations in the near-infrared wavelength range have been regularly carried out at the Crimean Astrophysical Observatory (CrAO) on the Tower Solar Telescope (TST-2). It began in the late 1990s by putting into operation the Universal Spectrophotometer (USPh) at the TST-2 and it continues up to the present time. In 2020 the observation process was modernized - the mirror control electronics and software were replaced. Work is currently underway to create a catalog of solar disk images obtained before the modernization of TST-2. Here we present fragments of the catalog - several examples of a full solar disk in He i 1083 nm from the USPh/TST-2 instrument and a brief description of the future catalog.

The diffuse interstellar band around 8620 Å

Context. Diffuse interstellar bands (DIBs) are interstellar absorption features that widely exist in the optical and near-infrared wavelength range. DIBs play an important role in the lifecycle of the interstellar medium and can also be used to trace the Galactic structure. Aims. We developed a set of procedures to automatically detect and measure the DIB around 8620 Å (the Gaia DIB) for a wide range of temperatures. The method was tested on ~5000 spectra from the Giraffe Inner Bulge Survey (GIBS) that has a spectral window similar to that of the Gaia–RVS spectra. Based on this sample, we studied the correlation between the equivalent width (EW) of the Gaia DIB and the interstellar reddening E(J − KS) toward the inner Galaxy, as well as the DIB intrinsic properties. Methods. Our procedure automatically checks and eliminates invalid cases, and then applies a specific local normalization. The DIB profile is fit with a Gaussian function. Specifically, the DIB feature is extracted from the spectra of late-type stars by subtracting the corresponding synthetic spectra. For early-type stars we applied a specific model based on the Gaussian process that needs no prior knowledge of the stellar parameters. In addition, we provide the errors contributed by the synthetic spectra and from the random noise. Results. After validation, we obtained 4194 reasonable fitting results from the GIBS database. An EW versus E(J − KS) relation is derived as E(J − KS) = 1.875 (±0.152) × EW − 0.011 (±0.048), according to E(B − V)∕EW = 2.721, which is highly consistent with previous results toward similar sightlines. After a correction based on the Vista Variables in the Via Lactea (VVV) database for both EW and reddening, the coefficient derived from individual GIBS fields, E(J − KS)∕EW = 1.884 ± 0.225, is also in perfect agreement with literature values. Based on a subsample of 1015 stars toward the Galactic center within − 3° &lt; b &lt; 3° and − 6° &lt; l &lt; 3°, we determined a rest-frame wavelength of the Gaia DIB as 8620.55 Å. Conclusions. The procedures for automatic detection and measurement of the Gaia DIB are successfully developed and have been applied to the GIBS spectra. A Gaussian profile is proved to be a proper and stable assumption for the Gaia DIB as no intrinsic asymmetry is found. A tight linearity of its correlation with the reddening is derived toward the inner Milky Way, which is consistent with previous results.

Light-induced release of the cardioprotective peptide angiotensin-(1–9) from thermosensitive liposomes with gold nanoclusters

Angiotensin-(1-9), a component of the non-canonical renin-angiotensin system, has a short half-life in blood. This peptide has shown to prevent and/or attenuate hypertension and cardiovascular remodeling. A controlled release of angiotensin-(1-9) is needed for its delivery to the heart. Our aim was to develop a drug delivery system for angiotensin-(1-9). Thermosensitive liposomes (LipoTherm) were prepared with gold nanoclusters (LipoTherm-AuNC) to increase the stability and reach a temporal and spatial control of angiotensin-(1-9) release. Encapsulation efficiencies of nearly 50% were achieved in LipoTherm, reaching a total angiotensin-(1-9) loading of around 180 μM. This angiotensin-(1–9)-loaded LipoTherm sized around 100 nm and exhibited a phase transition temperature of 43 °C. AuNC were grown on LipoTherm and the new hybrid nanosystem showed energy absorption in the near-infrared (NIR) wavelength range. By NIR laser irradiation, a controlled release of angiotensin-(1-9) was achieved from the LipoTherm-AuNC nanosystem. These nanosystems did not show any cytotoxic effect on cultured cardiomyocytes. Biological activity of angiotensin-(1-9) released from the LipoTherm-AuNC-based nanosystem was confirmed using an ex vivo Langendorff heart model.

Sharpening of Worldview-3 Satellite Images by Generating Optimal High-Spatial-Resolution Images

Compared to using images in the visible and near-infrared (VNIR) wavelength range only, remotely sensed satellite imagery from the spectral wavelengths of both VNIR and shortwave infrared (SWIR), such as Sentinel-2A and Worldview-3, is more effective for analyzing various types of information for tasks such as land cover mapping, environmental monitoring and land use change detection. In this manuscript, a new sharpening technique to enhance the spatial resolution of Worldview-3 satellite imagery with various spatial and spectral resolutions is proposed. Selected and synthesized band schemes were used to produce optimal panchromatic images; then, sharpened images were generated by applying the Gram-Schmidt adaptive (GSA) and Gram-Schmidt 2 (GS2) techniques, which are component substitution (CS)- and multiresolution analysis (MRA)-based algorithms, respectively. In addition, to minimize the spectral distortion of the initial sharpened image, a postprocessing methodology for spectral distortion reduction was developed. Qualitative and quantitative evaluation of the sharpened images showed that the pansharpening performance using the GS2 technique based on the selected band scheme and spectral distortion reduction was the best. To confirm the usability of the SWIR band, supervised classification based on machine learning was performed on the pansharpened images obtained by applying the technique proposed in this study and on the pansharpened images obtained by the VNIR bands only. The classification accuracy of the results using SWIR bands was higher than that of VNIR bands only. In particular, it was confirmed that the accuracy of the classification of artificial facilities known to be effective for SWIR bands was greatly improved.

Abundance measurements of H2O and carbon-bearing species in the atmosphere of WASP-127b confirm its supersolar metallicity

ABSTRACT The chemical abundances of exoplanet atmospheres may provide valuable information about the bulk compositions, formation pathways, and evolutionary histories of planets. Exoplanets with large, relatively cloud-free atmospheres, and which orbit bright stars provide the best opportunities for accurate abundance measurements. For this reason, we measured the transmission spectrum of the bright (V ∼ 10.2), large (1.37 RJ), sub-Saturn mass (0.19 MJ) exoplanet WASP-127b across the near-UV to near-infrared wavelength range (0.3–5 μm), using the Hubble and Spitzer Space Telescopes. Our results show a feature-rich transmission spectrum, with absorption from Na, H2O, and CO2, and wavelength-dependent scattering from small-particle condensates. We ran two types of atmospheric retrieval models: one enforcing chemical equilibrium, and the other which fit the abundances freely. Our retrieved abundances at chemical equilibrium for Na, O, and C are all supersolar, with abundances relative to solar values of 9$^{+15}_{-6}$, 16$^{+7}_{-5}$, and 26$^{+12}_{-9}$, respectively. Despite giving conflicting C/O ratios, both retrievals gave supersolar CO2 volume mixing ratios, which adds to the likelihood that WASP-127b’s bulk metallicity is supersolar, since CO2 abundance is highly sensitive to atmospheric metallicity. We detect water at a significance of 13.7σ. Our detection of Na is in agreement with previous ground-based detections, though we find a much lower abundance, and we also do not find evidence for Li or K despite increased sensitivity. In the future, spectroscopy with James Webb Space Telescope will be able to constrain WASP-127b’s C/O ratio, and may reveal the formation history of this metal-enriched, highly observable exoplanet.

Near-infrared photoresponse in Ge/Si quantum dots enhanced by localized surface plasmons supported by aluminum nanodisks

An array of plasmonic nanoparticles can sustain surface plasmon modes from visible to infrared spectral range and thus offers effective surface light trapping, enhancement of local fields, and interaction with the thin active regions of optical devices. We report the fabrication and optical characterization of a planar Ge/Si quantum dot (QD) detector grown on silicon-on-insulator (SOI) substrate for photodetection in the near-infrared telecommunication wavelength range. The multilayer Ge/Si QD heterostructures are near-field coupled to the adjacent layers of aluminum nanodisks on the detector top. The periodic Al disk arrays have the square lattice symmetry with a lattice constant of 400 nm and the disk diameter varying from 150 to 225 nm. A significant enhancement in the room-temperature detector sensitivity is achieved due to the excitation of localized surface plasmons supported by the metallic disks and radiative coupling to the SOI waveguide modes. Through extinction spectroscopy and numerical modeling, we confirm the emergence of nanoparticle-induced plasmon resonances near the Si–Al interface. We demonstrate that an appropriate choice of the array periodicity and the size of the metal disks is able to increase the photodetector's efficiency by ∼ 40× at λ=1.2μm and by 15× at λ≈1.55μm relative to a bare detector with no plasmonic structure. These outcomes pave the way toward the use of Al as a low-cost plasmonic material with potential applications in infrared photodetection similar to those of the noble metals.

The CARMENES search for exoplanets around M dwarfs

Existing and upcoming instrumentation is collecting large amounts of astrophysical data, which require efficient and fast analysis techniques. We present a deep neural network architecture to analyze high-resolution stellar spectra and predict stellar parameters such as effective temperature, surface gravity, metallicity, and rotational velocity. With this study, we firstly demonstrate the capability of deep neural networks to precisely recover stellar parameters from a synthetic training set. Secondly, we analyze the application of this method to observed spectra and the impact of the synthetic gap (i.e., the difference between observed and synthetic spectra) on the estimation of stellar parameters, their errors, and their precision. Our convolutional network is trained on synthetic PHOENIX-ACES spectra in different optical and near-infrared wavelength regions. For each of the four stellar parameters,Teff, logg, [M/H], andvsini, we constructed a neural network model to estimate each parameter independently. We then applied this method to 50 M dwarfs with high-resolution spectra taken with CARMENES (Calar Alto high-Resolution search for M dwarfs with Exo-earths with Near-infrared and optical Échelle Spectrographs), which operates in the visible (520–960 nm) and near-infrared wavelength range (960–1710 nm) simultaneously. Our results are compared with literature values for these stars. They show mostly good agreement within the errors, but also exhibit large deviations in some cases, especially for [M/H], pointing out the importance of a better understanding of the synthetic gap.

The GOGREEN and GCLASS surveys: first data release

ABSTRACT We present the first public data release of the GOGREEN (Gemini Observations of Galaxies in Rich Early Environments) and GCLASS (Gemini CLuster Astrophysics Spectroscopic Survey) surveys of galaxies in dense environments, spanning a redshift range 0.8 &amp;lt; z &amp;lt; 1.5. The surveys consist of deep, multiwavelength photometry and extensive Gemini GMOS spectroscopy of galaxies in 26 overdense systems ranging in halo mass from small groups to the most massive clusters. The objective of both projects was primarily to understand how the evolution of galaxies is affected by their environment, and to determine the physical processes that lead to the quenching of star formation. There was an emphasis on obtaining unbiased spectroscopy over a wide stellar mass range (M ≳ 2 × 1010 M⊙), throughout and beyond the cluster virialized regions. The final spectroscopic sample includes 2771 unique objects, of which 2257 have reliable spectroscopic redshifts. Of these, 1704 have redshifts in the range 0.8 &amp;lt; z &amp;lt; 1.5, and nearly 800 are confirmed cluster members. Imaging spans the full optical and near-infrared wavelength range, at depths comparable to the UltraVISTA survey, and includes Hubble Space Telescope/Wide Field Camera 3 F160W (GOGREEN) and F140W (GCLASS). This data release includes fully reduced images and spectra, with catalogues of advanced data products including redshifts, line strengths, star formation rates, stellar masses, and rest-frame colours. Here, we present an overview of the data, including an analysis of the spectroscopic completeness and redshift quality.

Numerical investigation of a small footprint plasmonic Bragg grating structure with a high extinction ratio

In this paper, miniaturized design of a plasmonic Bragg grating filter is investigated via the finite element method (FEM). The filter is based on a plasmonic metal-insulator-metal waveguide deposited on a quartz substrate. The corrugated Bragg grating designed for near-infrared wavelength range is structured on both sides of the waveguide. The spectral characteristics of the filter are studied by varying the geometric parameters of the filter design. As a result, the maximum ER and bandwidth of 36.2 dB and 173 nm is obtained at λBragg=976 nm with a filter footprint of as small as 1.0 x 8.75 µm2, respectively. The ER and bandwidth can be further improved by increasing the number of grating periods and the strength of the grating, respectively. Moreover, the Bragg grating structure is quite receptive to the refractive index of the medium. 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High performance vanadium dioxide based active nano plasmonic filter and switch

We have designed a compact active nano-plasmonic waveguide-based filter and switch in a Fabry Perot structure, in which Vanadium dioxide (VO2) is used as the active material to form an Au/VO2/Au tri-layer structure, which is based on the effect of the electrical-driven phase transformation from the VO2 layer. The largest modulation depth and lowest insertion loss of the Au/VO2/Au tri-layer based FP resonator are 44.77 dB and 1.43 dB respectively in the near-infrared wavelength range from 1400 nm to 2100 nm. In addition, a moderate quality factor of 146 and a high figure-of-merit of 33.31 can be achieved by using a short nano-plasmonic waveguide. The compact size, wavelength tunability, high modulation depth and low insertion loss indicate that the proposed active nano-plasmonic waveguide can be used in a high-density integrated optical circuit.