Active tuning of near-infrared electromagnetic responses in the graphene/silicon hybrid nanohole arrays by electrical control

2022 ◽  
Vol 105 (3) ◽  
Author(s):  
Hong Wang ◽  
Ji Zhou ◽  
Duofu Song ◽  
Yi Wang
Sensors ◽  
2019 ◽  
Vol 19 (9) ◽  
pp. 2182 ◽  
Author(s):  
Chiara Valsecchi ◽  
Luis Enrique Gomez Armas ◽  
Jacson Weber de Menezes

Several fabrication techniques are recently used to produce a nanopattern for sensing, as focused ion beam milling (FIB), e-beam lithography (EBL), nanoimprinting, and soft lithography. Here, interference lithography is explored for the fabrication of large area nanohole arrays in metal films as an efficient, flexible, and scalable production method. The transmission spectra in air of the 1 cm2 substrate were evaluated to study the substrate behavior when hole-size, periodicity, and film thickness are varied, in order to elucidate the best sample for the most effective sensing performance. The efficiency of the nanohole array was tested for bulk sensing and compared with other platforms found in the literature. The sensitivity of ~1000 nm/RIU, achieved with an array periodicity in the visible range, exceeds near infrared (NIR) performances previously reported, and demonstrates that interference lithography is one of the best alternative to other expensive and time-consuming nanofabrication methods.


Nanophotonics ◽  
2017 ◽  
Vol 6 (6) ◽  
pp. 1239-1262 ◽  
Author(s):  
Pai-Yen Chen ◽  
Christos Argyropoulos ◽  
Mohamed Farhat ◽  
J. Sebastian Gomez-Diaz

AbstractIn this paper, we review and discuss how the recently discovered two-dimensional (2D) Dirac materials, particularly graphene, may be utilized as new efficient platforms for excitations of propagating and localized surface plasmon polaritons (SPPs) in the terahertz (THz) and mid-infrared (MIR) regions. The surface plasmon modes supported by the metallic 2D materials exhibit tunable plasmon resonances that are essential, yet missing, ingredients needed for THz and MIR photonic and optoelectronic devices. We describe how the atomically thin graphene monolayer and metamaterial structures based on it may tailor and control the spectral, spatial, and temporal properties of electromagnetic radiation. In the same frequency range, the newly unveiled nonlocal, nonlinear, and nonequilibrium electrodynamics in graphene show a variety of nonlinear and amplifying electromagnetic responses, whose potential applications are yet unexplored. With these 2D material platforms, virtually all plasmonic, optoelectronic, and nonlinear functions found in near-infrared (NIR) and visible devices can be analogously transferred to the long-wavelength regime, even with enhanced tunability and new functionalities. The spectral range from THz to MIR is particularly compelling because of the many spectral fingerprints of key chemical, gas, and biological agents, as well as a myriad of remote sensing, imaging, communication, and security applications.


2021 ◽  
Vol 11 (13) ◽  
pp. 6012
Author(s):  
Emilija Petronijevic ◽  
Ramin Ghahri ◽  
Concita Sibilia

Chiral plasmonic nanostructures with tunable handedness-dependent absorption in the visible and infrared offer chiro-optical control at the nanoscale. Moreover, coupling them with emitting layers could lead to chiral nanosources, important for nanophotonic circuits. Here, we propose plasmonic elliptical nanohole arrays (ENHA) for circularly dependent near-infrared and visible emission. We first investigate broadband chiral behavior in an Au-ENHA embedded in glass by exciting it with plane waves. We then study the coupling of ENHA with a thin emitting layer embedded in glass; we focus on the emission wavelengths which provided high chirality in plane-wave simulations. Our novel simulation set-up monitors the chirality of the far-field emission by properly averaging a large set of homogeneously distributed, randomly oriented quantum sources. The intrinsic chirality of ENHA influences the circular polarization degree of the emitting layer. Finally, we study the emission dependence on the field distribution at the excitation wavelength. We demonstrate the chiral absorption and emission properties for Au-ENHA emitting in the near-infrared range, and for Ag-ENHA which is excited in green range and emits in the Lumogen Red range. The simple geometry of ENHA can be fabricated with low-cost nanosphere lithography and be covered with emission gel. We thus believe that this design can be of great importance for tunable chiral nanosources.


2017 ◽  
Vol 11 (03) ◽  
pp. 1 ◽  
Author(s):  
Michael Bendayan ◽  
Roi Sabo ◽  
Roee Zolberg ◽  
Yaakov Mandelbaum ◽  
Avraham Chelly ◽  
...  

Nanoscale ◽  
2020 ◽  
Vol 12 (14) ◽  
pp. 7875-7887 ◽  
Author(s):  
Ying Lan ◽  
Xiaohui Zhu ◽  
Ming Tang ◽  
Yihan Wu ◽  
Jing Zhang ◽  
...  

A near-infrared (NIR) activated theranostic nanoplatform based on upconversion nanoparticles (UCNPs) is developed in order to overcome the hypoxia-associated resistance in photodynamic therapy by photo-release of NO upon NIR illumination.


2020 ◽  
Vol 56 (43) ◽  
pp. 5819-5822
Author(s):  
Jing Zheng ◽  
Yongzhuo Liu ◽  
Fengling Song ◽  
Long Jiao ◽  
Yingnan Wu ◽  
...  

In this study, a near-infrared (NIR) theranostic photosensitizer was developed based on a heptamethine aminocyanine dye with a long-lived triplet state.


2020 ◽  
Vol 48 (6) ◽  
pp. 2657-2667
Author(s):  
Felipe Montecinos-Franjola ◽  
John Y. Lin ◽  
Erik A. Rodriguez

Noninvasive fluorescent imaging requires far-red and near-infrared fluorescent proteins for deeper imaging. Near-infrared light penetrates biological tissue with blood vessels due to low absorbance, scattering, and reflection of light and has a greater signal-to-noise due to less autofluorescence. Far-red and near-infrared fluorescent proteins absorb light >600 nm to expand the color palette for imaging multiple biosensors and noninvasive in vivo imaging. The ideal fluorescent proteins are bright, photobleach minimally, express well in the desired cells, do not oligomerize, and generate or incorporate exogenous fluorophores efficiently. Coral-derived red fluorescent proteins require oxygen for fluorophore formation and release two hydrogen peroxide molecules. New fluorescent proteins based on phytochrome and phycobiliproteins use biliverdin IXα as fluorophores, do not require oxygen for maturation to image anaerobic organisms and tumor core, and do not generate hydrogen peroxide. The small Ultra-Red Fluorescent Protein (smURFP) was evolved from a cyanobacterial phycobiliprotein to covalently attach biliverdin as an exogenous fluorophore. The small Ultra-Red Fluorescent Protein is biophysically as bright as the enhanced green fluorescent protein, is exceptionally photostable, used for biosensor development, and visible in living mice. Novel applications of smURFP include in vitro protein diagnostics with attomolar (10−18 M) sensitivity, encapsulation in viral particles, and fluorescent protein nanoparticles. However, the availability of biliverdin limits the fluorescence of biliverdin-attaching fluorescent proteins; hence, extra biliverdin is needed to enhance brightness. New methods for improved biliverdin bioavailability are necessary to develop improved bright far-red and near-infrared fluorescent proteins for noninvasive imaging in vivo.


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