Abstuact-Mode-discriminating electrooptic sampling (MEOS) of coplanar waveguides was shown to discriminate between the symmetric quasi-TEM guided mode and asymmetric field distributions including unguided electromagnetic radiation. Radiation generated in a photoconductive switch and reflected from the back of the substrate was unambiguously identified. Ultrafast sampling of devices showed features in the transmitted pulse due to multiple substrate reflections. These features are removed using MEOS, leading to increased accuracy in determination of s-parameters. J. Allam is with the

An in-plane gate field-effect transistor is characterized by ultrafast electro-optic sampling. The transistor is monolithically integrated with photoconductive switches in coplanar waveguide and <0.5 ps measurement time resolution is achieved. The gate-drain capacitance of the transistor is obtained as 1.8 fF at zero drain voltage from displacement current transients. The gate-drain capacitance is dominated by parasitic capacitance and the intrinsic gate-drain capacitance is estimated as less than 0.2 fF.

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We report on a new polymer light emitting diode (PLED) based on a blend of immiscible polymers.The device shows high efficiency and current density over a broad range of driving voltage, therefore exhibiting very high brightness.The polymer film morphology plays a very important role in determining the device performance, and it can be controlled by changing the blend ratio as well as the polymers molecular weight.The high performance are discussed in terms of "barrier free" injection into excitonic states.A predicted lifetime in excess of 10,000 hours has already been achieved, making this device structure an ideal candidate for backlighting and monocromatic application.