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The electronic structure of Vanadium pentoxide (V2O5), a transition metal oxide with an exceedingly large work function of 7.0 eV, is studied via ultraviolet, inverse and x-ray photoemission spectroscopy. Very deep lying electronic states with electron affinity and ionization energy (IE) of 6.7 eV and 9.5 eV, respectively, are found. Contamination due to air exposure changes the electronic structure due to the partial reduction of vanadium to V+4 state. It is shown that V2O5 is a n-type material that can be used for efficient hole-injection into materials with an IE larger than 6 eV, such as 4,4′-Bis(N-carbazolyl)-1,1′-bipheny (CBP). The formation of an interface dipole and band bending is found to lead to a very small energy barrier between the transport levels at the V2O5/CBP interface. [ABSTRACT FROM AUTHOR]

We report on various sexiphenyl derivatives as gain media in organic solid-state lasers. The molecules involved in this research are simple p-sexiphenyl, the laser dye molecule 2,5,2””’,5””’-tetra-t-butyl-p-sexiphenyl (TBS) and the spirolinked sexiphenyl-derivative 2,7-bis(biphenyl-4-yl)-2’,7’-di-tert-butyl-9,9’-spirobifluorene. It appears that the morphology of vacuum-deposited thin films is highly dependent on the sterical dimensions of the respective molecules. Whereas thin films based on simple p-sexiphenyl comprise large clusters which significantly deteriorate their waveguiding properties; films formed by TBS, and the spiroderivative show a dramatically improved morphology with reduced surface roughness. Therefore amplified spontaneous emission (ASE) and lasing are demonstrated in both of the last but not in films based on p-sexiphenyl. Second-order distributed-feedback lasers with TBS as the active medium have been prepared with an emission between 390 and 435 nm depending on the grating period of the Bragg reflector. While the ASE characteristics are similar in films formed by TBS and the spiroderivative, TBS exhibits even superior laser threshold densities which are as low as 45 μJ/cm2 at a wavelength of 396 nm. [ABSTRACT FROM AUTHOR]

An examination is done on the subthreshold characteristics of ballistic carbon nanotube field effect transistors (CNTFETs) revealing the complex band structure effect. In conclusion, it is observed that nanoscale CNTFETs can perform better with a larger on-off current ration and better subthreshold swing if the CNT has a larger band gap.

An examination is done of fabricated fully patterned all-organic thin-film transistors with a variety of organic polymer insulators. In conclusion, a strong correlation is observed between the solvents used for the dielectrics, dielectric constant of the insulator, and the field-effect mobility.

The objective of this letter is to show the potential of amorphous indium gallium zinc oxide (IGZO) thin-film transistors (TFT) for designing radio frequency (RF) communication systems operating in the gigahertz regime. For that purpose, the self-mixing operation of in-house fabricated IGZO-TFTs beyond their transit frequency ($f_{T}$) is reported. The bottom-gate, top-contact TFTs have an $f_{T}$ of 40 MHz including the device interconnects. A differential RF self-mixing circuit was fabricated to act as an RF detector and frequency doubler. The detector shows a peak voltage responsivity ($R_{V}$) and a minimum noise equivalent power of 445 V/W and 0.1 nW/ ${\sqrt {\text {Hz}}}$ at 50 MHz and 2 V/W and 30 nW/ ${\sqrt {\text {Hz}}}$ at 1 GHz, respectively, at a chopping frequency of 28 kHz. As a frequency doubler, the circuit can generate a second-harmonic output voltage up to −36 dBV for an 8-dBV RF input voltage at 100 MHz. [ABSTRACT FROM AUTHOR]

European Standards and Guidelines for Quality Assurance in tertiary education at Universities of Applied Sciences recommend a high level of competence orientation. This can be achieved and evaluated by the definition of Learning Outcomes. Furthermore, these Outcomes can assure a comparison of the level of education after graduation. Efforts should be made to achieve this form of Quality Assurance for the professional education of physiotherapists.