Thermal tunability of monolithic polymer microcavities

We demonstrate the thermal tunability of the emission of polymer embedded in microcavities. The large thermo-optic coefficients of a conjugated polymer is combined with the possibility to tailor the emission properties by means of cavities acting as optical filters. Both the transmission and the photoluminescence spectra of the polymer in cavities can be finely tuned with slopes up to about -0.2 nm/degreesC. Such an effect could be exploited to realize thermally tunable organic light-emitting devices for optical communication or sensing applications. (20 References)

Quantum cascade lasers for biosensing applications

Quantum cascade lasers represent nowadays a mature technology to obtain laser sources in the medium and far infrared region (up to THz). Several advantages with respect to other coherent sources make this kind of lasers particularly attractive: the emission frequency can be selected by properly designing the growth structure, the emission wavelength is tunable with a very good precision and a high optical power in the IR range can be emitted in a spot of small size. These properties make them suitable for several applications, including gas spectroscopy in the IR range. In this work we introduce different types of quantum cascade lasers and we provide a description of their performances and properties, showing that they are suitable candidates for biosensing applications. (17 References)

Thermal resistance measurement of GaAs MESFETs by means of photocurrent spectrum analysis and comparison with simulations

e power-dependent behaviour of channel temperature in GaAs MESFETs has been measured by using the photocurrent method. Measurements were performed for different packaging of the MESFET. The effective thermal resistance of the devices has been extracted and related to the packaging. We compared the experimental results to hydrodynamic simulations and derived a suitable expression for the thermal conductivity