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Intensity tunable infrared broadband absorbers based on VO2 phase transition using planar layered thin films.

Kocer H, Butun S, Palacios E, Liu Z, Tongay S, Fu D, Wang K, Wu J, Aydin K - Sci Rep (2015)

Bottom Line: Here, we demonstrate a simple, lithography-free approach for obtaining a resonant and dynamically tunable broadband absorber based on vanadium dioxide (VO2) phase transition.Using planar layered thin film structures, where top layer is chosen to be an ultrathin (20 nm) VO2 film, we demonstrate broadband IR light absorption tuning (from ~90% to ~30% in measured absorption) over the entire mid-wavelength infrared spectrum.Broadband tunable absorbers can find applications in absorption filters, thermal emitters, thermophotovoltaics and sensing.

View Article: PubMed Central - PubMed

Affiliation: Department of Electrical Engineering and Computer Science, Northwestern University, Evanston, IL 60208, USA.

ABSTRACT
Plasmonic and metamaterial based nano/micro-structured materials enable spectrally selective resonant absorption, where the resonant bandwidth and absorption intensity can be engineered by controlling the size and geometry of nanostructures. Here, we demonstrate a simple, lithography-free approach for obtaining a resonant and dynamically tunable broadband absorber based on vanadium dioxide (VO2) phase transition. Using planar layered thin film structures, where top layer is chosen to be an ultrathin (20 nm) VO2 film, we demonstrate broadband IR light absorption tuning (from ~90% to ~30% in measured absorption) over the entire mid-wavelength infrared spectrum. Our numerical and experimental results indicate that the bandwidth of the absorption bands can be controlled by changing the dielectric spacer layer thickness. Broadband tunable absorbers can find applications in absorption filters, thermal emitters, thermophotovoltaics and sensing.

No MeSH data available.


Related in: MedlinePlus

The angular dependence of absorption at λ = 4 μm for the structure with 500 nm thick PMMA.Black and red curves represents i-VO2 and m-VO2, respectively. (a) TE polarization. (b) TM polarization.
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f5: The angular dependence of absorption at λ = 4 μm for the structure with 500 nm thick PMMA.Black and red curves represents i-VO2 and m-VO2, respectively. (a) TE polarization. (b) TM polarization.

Mentions: The angular dependence of absorption spectra for TE and TM polarizations were calculated using transfer-matrix method within the structure of 500 nm thick PMMA at 4 μm wavelength. In TE polarization, the electric field is normal to the incidence plane (x-y plane in Fig. 1), whereas it is inside the incidence plane in TM polarization. We note that TM polarization has slightly broader angular incidence and larger dynamic absorption tunability with respect to TE polarization. Nevertheless, the results in Fig. 5 show that the features of the broadband absorption and temperature tuning of the absorption are valid within a broad angular incidence of up to 60° for both polarizations.


Intensity tunable infrared broadband absorbers based on VO2 phase transition using planar layered thin films.

Kocer H, Butun S, Palacios E, Liu Z, Tongay S, Fu D, Wang K, Wu J, Aydin K - Sci Rep (2015)

The angular dependence of absorption at λ = 4 μm for the structure with 500 nm thick PMMA.Black and red curves represents i-VO2 and m-VO2, respectively. (a) TE polarization. (b) TM polarization.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4543955&req=5

f5: The angular dependence of absorption at λ = 4 μm for the structure with 500 nm thick PMMA.Black and red curves represents i-VO2 and m-VO2, respectively. (a) TE polarization. (b) TM polarization.
Mentions: The angular dependence of absorption spectra for TE and TM polarizations were calculated using transfer-matrix method within the structure of 500 nm thick PMMA at 4 μm wavelength. In TE polarization, the electric field is normal to the incidence plane (x-y plane in Fig. 1), whereas it is inside the incidence plane in TM polarization. We note that TM polarization has slightly broader angular incidence and larger dynamic absorption tunability with respect to TE polarization. Nevertheless, the results in Fig. 5 show that the features of the broadband absorption and temperature tuning of the absorption are valid within a broad angular incidence of up to 60° for both polarizations.

Bottom Line: Here, we demonstrate a simple, lithography-free approach for obtaining a resonant and dynamically tunable broadband absorber based on vanadium dioxide (VO2) phase transition.Using planar layered thin film structures, where top layer is chosen to be an ultrathin (20 nm) VO2 film, we demonstrate broadband IR light absorption tuning (from ~90% to ~30% in measured absorption) over the entire mid-wavelength infrared spectrum.Broadband tunable absorbers can find applications in absorption filters, thermal emitters, thermophotovoltaics and sensing.

View Article: PubMed Central - PubMed

Affiliation: Department of Electrical Engineering and Computer Science, Northwestern University, Evanston, IL 60208, USA.

ABSTRACT
Plasmonic and metamaterial based nano/micro-structured materials enable spectrally selective resonant absorption, where the resonant bandwidth and absorption intensity can be engineered by controlling the size and geometry of nanostructures. Here, we demonstrate a simple, lithography-free approach for obtaining a resonant and dynamically tunable broadband absorber based on vanadium dioxide (VO2) phase transition. Using planar layered thin film structures, where top layer is chosen to be an ultrathin (20 nm) VO2 film, we demonstrate broadband IR light absorption tuning (from ~90% to ~30% in measured absorption) over the entire mid-wavelength infrared spectrum. Our numerical and experimental results indicate that the bandwidth of the absorption bands can be controlled by changing the dielectric spacer layer thickness. Broadband tunable absorbers can find applications in absorption filters, thermal emitters, thermophotovoltaics and sensing.

No MeSH data available.


Related in: MedlinePlus