We have fabricated organic thin-film transistor (OTFT)-driven active matrix liquid crystal displays on flexible polymeric substrates. These small displays have 16×16 pixel polymer-dispersed liquid crystal arrays addressed by pentacene active layer OTFTs. The displays were fabricated using a low-temperature process (<110 °C) on flexible polyethylene naphthalate film and are operated as reflective active matrix displays.

In the absence of charge storage or slow polarization in the gate dielectric, the hysteresis in the current-voltage (I−V) characteristics of pentacene-based organic thin-film transistors (OTFTs) is dominated by trapped electrons in the semiconductor. The immobile previously stored negative charge requires extra holes to balance it, resulting in the early establishment of the channel and extra drain current. Inferred from I−V characteristics, this simple electrostatic model qualitatively explains memory effects in pentacene-based OTFTs, and was verified by a time domain measurement.

We present a new device capable of demultiplexing Tb/s pulse trains. It requires less than one picojoule of switching energy and can be integrated on a chip. The device consists of an optical nonlinear element asymmetrically placed in a short fiber loop. Its switching time is determined by the off-center position of the nonlinear element within the loop, and therefore it can use the strong, slow optical nonlinearities found in semiconductors, which all other fast demultiplexers seek to avoid. We demonstrate the switch's operation at 50 Gb/s using 600 fJ control pulses

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We report a strong field effect observed at room temperature in epitaxially synthesized, as opposed to exfoliated, graphene. The graphene formed on the silicon face of a 4H silicon carbide substrate was photolithographically patterned into isolated active regions for the semimetal graphene-based transistors. Gold electrodes and a polymer dielectric were used in the top-gate transistors. The demonstration of a field effect mobility of 535 cm 2 /Vs was attributed to the transistor geometry that maximizes conductance modulation, although the mobility is lower than observed in exfoliated graphene possibly due to grain boundaries caused by the rough morphology of the substrate surface.