“…In this context, a relevant approach consists of designing a cavity presenting a resonant absorption band (which does not have to be critically narrow), allowing perfect absorption for a specific polarization of light, angle of incidence, and wavelength. Near this “darkness” point, the spectrum of the Δ phase coefficient measured by ellipsometry presents a very sharp jump that is ideal for sensing applications . Following this approach, label‐free biosensing with a limit of detection at the pM level and noncontact thermometry with a 10 −4 °C accuracy was reported using few‐layer structures, including either continuous layers or granular layers with a tailored effective dielectric function .…”
Section: Film Interferencementioning
confidence: 99%
“…Near the “darkness” point of perfect absorption, a sharp jump occurs in the spectrum of the Δ ellipsometric phase coefficient. Reproduced with permission . Copyright 2018, WILEY‐VCH Verlag GmbH & Co. KGaA.…”
Section: Film Interferencementioning
confidence: 99%
“…Near this "darkness" point, the spectrum of the Δ phase coefficient measured by ellipsometry presents a very sharp jump that is ideal for sensing applications. [69][70][71] Following this approach, label-free biosensing with a limit of detection at the pM level [69,70] and noncontact thermometry with a 10 À4 C [71] accuracy was reported using few-layer structures, including either continuous layers [69,70] or granular layers with a tailored effective dielectric function. [71] The latter example is shown in Figure 9.…”
Section: Narrowband Featuresmentioning
confidence: 99%
“…[69][70][71] Following this approach, label-free biosensing with a limit of detection at the pM level [69,70] and noncontact thermometry with a 10 À4 C [71] accuracy was reported using few-layer structures, including either continuous layers [69,70] or granular layers with a tailored effective dielectric function. [71] The latter example is shown in Figure 9. The nanomaterial consists of a layer of Ag nanoparticles sandwiched between dielectric layers, the structure standing on a Si substrate (top-left panel).…”
Functional materials with a tailored optical response are needed for applications including coloring, optical instrumentation, data encryption, thermal radiation shaping, energy harvesting, and environmental or biological sensing. A given application requires the material to absorb, transmit, reflect, or scatter light in a suitable way, in a specific, narrow, or broad spectral range selected in the visible or infrared. To achieve the optical response and functionality needed, it is appealing to design nanomaterials with a suitable composition and a properly engineered structure, and this should ideally be realized with high‐throughput and cost‐effective fabrication methods. Herein, the aim is to provide a view on some very recently reported functional nanomaterials showing an optical response tailored for applications by lithography‐free methods. It is illustrated how assembling tailor‐made nanostructures based on the expanding library of optical materials (and their specific wavelength‐dependent dielectric functions) enables harnessing a variety of optical resonances (plasmonic, epsilon near zero, high refractive index Mie, film interference) to tailor the nanomaterials' optical response. It is also shown that building the nanostructures from novel optical materials brings special functionalities, such as a switchable response. Examples of applications are put forward.
“…In this context, a relevant approach consists of designing a cavity presenting a resonant absorption band (which does not have to be critically narrow), allowing perfect absorption for a specific polarization of light, angle of incidence, and wavelength. Near this “darkness” point, the spectrum of the Δ phase coefficient measured by ellipsometry presents a very sharp jump that is ideal for sensing applications . Following this approach, label‐free biosensing with a limit of detection at the pM level and noncontact thermometry with a 10 −4 °C accuracy was reported using few‐layer structures, including either continuous layers or granular layers with a tailored effective dielectric function .…”
Section: Film Interferencementioning
confidence: 99%
“…Near the “darkness” point of perfect absorption, a sharp jump occurs in the spectrum of the Δ ellipsometric phase coefficient. Reproduced with permission . Copyright 2018, WILEY‐VCH Verlag GmbH & Co. KGaA.…”
Section: Film Interferencementioning
confidence: 99%
“…Near this "darkness" point, the spectrum of the Δ phase coefficient measured by ellipsometry presents a very sharp jump that is ideal for sensing applications. [69][70][71] Following this approach, label-free biosensing with a limit of detection at the pM level [69,70] and noncontact thermometry with a 10 À4 C [71] accuracy was reported using few-layer structures, including either continuous layers [69,70] or granular layers with a tailored effective dielectric function. [71] The latter example is shown in Figure 9.…”
Section: Narrowband Featuresmentioning
confidence: 99%
“…[69][70][71] Following this approach, label-free biosensing with a limit of detection at the pM level [69,70] and noncontact thermometry with a 10 À4 C [71] accuracy was reported using few-layer structures, including either continuous layers [69,70] or granular layers with a tailored effective dielectric function. [71] The latter example is shown in Figure 9. The nanomaterial consists of a layer of Ag nanoparticles sandwiched between dielectric layers, the structure standing on a Si substrate (top-left panel).…”
Functional materials with a tailored optical response are needed for applications including coloring, optical instrumentation, data encryption, thermal radiation shaping, energy harvesting, and environmental or biological sensing. A given application requires the material to absorb, transmit, reflect, or scatter light in a suitable way, in a specific, narrow, or broad spectral range selected in the visible or infrared. To achieve the optical response and functionality needed, it is appealing to design nanomaterials with a suitable composition and a properly engineered structure, and this should ideally be realized with high‐throughput and cost‐effective fabrication methods. Herein, the aim is to provide a view on some very recently reported functional nanomaterials showing an optical response tailored for applications by lithography‐free methods. It is illustrated how assembling tailor‐made nanostructures based on the expanding library of optical materials (and their specific wavelength‐dependent dielectric functions) enables harnessing a variety of optical resonances (plasmonic, epsilon near zero, high refractive index Mie, film interference) to tailor the nanomaterials' optical response. It is also shown that building the nanostructures from novel optical materials brings special functionalities, such as a switchable response. Examples of applications are put forward.
“…[39][40][41][42] They are also called lithography-free metasurfaces. [43,44] The random Bi-Al 2 O 3 metasurfaces considered in this work have been intentionally designed to achieve a broad plasmonic response to light in the ultraviolet-visible region of the spectrum [45] and optical switching upon heating. [28] Furthermore, these PCRMs have been prepared on Si substrates suitable for complementary metal-oxide-semiconductor integration.…”
that differ strongly from those of the constituent materials. Due to this remarkable flexibility, thin-film nanocomposites belong per se to the class of metasurfaces, whose fields of applications are constantly growing in key technological areas, including communications, energy, catalysis, and medicine. In the field of nanophotonics, the use of metasurfaces formed by planar arrangements of metallic and dielectric nanostructures has enabled the control of light at subwavelength scales, allowing light manipulation and processing in ways that are impossible to achieve with natural materials. [1][2][3][4] In particular, plasmonic metasurfaces based on nanostructured noble metals, either embedded in a dielectric film or deposited on top of a substrate, have shown extraordinary capabilities to strongly absorb, scatter, or confine incident light. More recently, nanostructures formed by high-index dielectric materials (mainly semiconductors such as Si and Ge) have gained momentum due to the particularities of their resulting electric and magnetic Mie resonances and have opened the field of the so-called Mie-resonant metaphotonics (also termed as Mie-tronics). [3,5,6] A relevant outcome of the improved understanding of these resonant phenomena has been acknowledged that there are alternative materials to the noble metals or conventional semiconductors that show plasmonic and Mie resonances, and, furthermore, that are better suited to address some specific nanophotonics applications. Among them are materials that offer plasmonic response in the ultraviolet, can withstand resonances at high temperature, or can be activated upon external excitation. [7][8][9][10] Bismuth (Bi) is one of such alternative materials and stands out due to its particular electronic structure, and optical and thermoelectronic properties. [11][12][13][14] Only very recently it has been shown that its electronic band structure displays giant interband electronic transitions in the mid-infrared, which, in turn, endows the dielectric function ε with a unique property that enables Bi-based nanostructures to show a dual behavior, enabling both plasmonic-like resonances in the ultraviolet and visible regions of the spectrum, and high-refractive-index Mie resonances in the near-and mid-infrared regions of the spectrum. [15,16] So far, metasurfaces based on Bi nanostructures have found applications in integrated photonic devices as perfect Random metasurfaces based on disordered phase-change nanostructures with broadband ultraviolet-visible plasmonic properties are fantastic platforms for the development of active photonic components due to their versatility. Here optical ON-OFF switching upon nanosecond laser irradiation of Bi-based random metasurfaces is demonstrated profiting from the solid-liquid phase transition of the Bi nanostructures. The fast switching time is revealed by using single-pulse real-time reflectivity measurements with sub-nanosecond temporal resolution. A sudden reflectivity decrease is observed upon laser excitation, triggered by hea...
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
