Claes-Göran Granqvist

Bio: Claes-Göran Granqvist is an academic researcher from Uppsala University. The author has contributed to research in topics: Electrochromism & Thin film. The author has an hindex of 73, co-authored 535 publications receiving 31523 citations. Previous affiliations of Claes-Göran Granqvist include Chalmers University of Technology & Texas A&M University.

Electrochromic vanadium pentoxide

Abstract: Interest in vanadium pentoxide (V205) as an electrochromic material has increased with the realization that V205 has suitable properties for counter electrode applications in variable transmittance electrochromic devices. Vari- able transmittance devices require a charge balancing counter electrode whose optical properties either contribute to, or at least do not interfere with, the overall transmittance modulation. Preliminary studies have shown that V205 exhibits anodic coloration in the blue and near-UV for lithium intercalation/deintercalation and is thus a suitable counter electrode to cathodically coloring electrochromic materials such as tungsten trioxide (W03).

Nickel oxide thin film sensor for fluctuation-enhanced gas sensing of formaldehyde

Abstract: Nanocrystalline nickel-oxide-based thin films were prepared by advanced reactive gas deposition, and the response of these films to formaldehyde was studied by fluctuation-enhanced sensing. Morphological and structural analyses showed porous deposits of nickel oxide particles with face-centered cubic structure. Resistance fluctuations were measured upon exposure to ethanol, formaldehyde and methane at 200 °C. Power density spectra were used to quantify the response. The response to formaldehyde was higher than to ethanol at 200 °C, and no significant response was observed for methane thus demonstrating some gas-species selectivity.

Aluminium oxide — Poly(vinyl acetate) composite electrolyte for electrochromic devices

Abstract: This report describes composite proton electrolytes composed of nanosize activated aluminium oxide particles with different surface acidity suspended in a poly(vinyl acetate)/glycerine matrix The conductivity of the composite was found to increase by going from basic to neutral to acidic aluminium oxide Tests in laminated electrochromic devices with tungsten oxide and nickel hydroxide films showed that the acidic electrolyte is compatible with WO3, the basic electrolyte is compatible with Ni(OH)2, and the neutral electrolyte is compatible with both of the electrodes

Facts, myths and fights about the kljn classical physical key exchanger

Abstract: This paper deals with the Kirchhoff-law-Johnson-noise (KLJN) classical statistical physical key exchange method and surveys criticism - often stemming from a lack of understanding of its underlying premises or from other errors - and our related responses against these, often unphysical, claims. Some of the attacks are valid, however, an extended KLJN system remains protected against all of them, implying that its unconditional security is not impacted.

Graphene photonics and optoelectronics

Abstract: The richness of optical and electronic properties of graphene attracts enormous interest. Graphene has high mobility and optical transparency, in addition to flexibility, robustness and environmental stability. So far, the main focus has been on fundamental physics and electronic devices. However, we believe its true potential lies in photonics and optoelectronics, where the combination of its unique optical and electronic properties can be fully exploited, even in the absence of a bandgap, and the linear dispersion of the Dirac electrons enables ultrawideband tunability. The rise of graphene in photonics and optoelectronics is shown by several recent results, ranging from solar cells and light-emitting devices to touch screens, photodetectors and ultrafast lasers. Here we review the state-of-the-art in this emerging field.