Research in organic electronics has included advances in materials, devices, and processes. Device architectures, increasingly complex circuitry, reliable fabrication methods, and new semiconductors are enabling the incorporation of organic electronic components in products including OLED displays and flexible electronic paper.

Pentacene-based thin-film integrated circuits patterned only with polymeric shadow masks and powered by near-field coupling at radio frequencies of 125 kHz and above 6 MHz have been demonstrated. Sufficient amplitude modulation of the rf field was obtained to externally detect a clock signal generated by the integrated circuit. The circuits operate without the use of a diode rectification stage. This demonstration provides the basis for more sophisticated low-cost rf transponder circuitry using organic semiconductors.

Widely tuned room temperature terahertz quantum cascade laser sources based on difference-frequency generation Appl. Phys. Lett. 101, 251121 (2012) Noise amplification by chaotic dynamics in a delayed feedback laser system and its application to nondeterministic random bit generation Chaos 22, 047513 (2012) Effect of the number of quantum dot layers and dual state emission on the performance of InAs/InGaAs passively mode-locked lasers Appl. Phys. Lett. 101, 251115 (2012) Ultrafast polarization modulation in vertical cavity surface emitting lasers with frequency dependent current injection Appl.

A novel approach to producing p-type ZnSe epitaxial layers is reported which involves nitrogen atom beam doping during molecular beam epitaxial growth. Net acceptor concentrations as large as 3.4×1017 cm−3 have been measured in nitrogen atom beam doped ZnSe/GaAs heteroepitaxial layers which represents the highest acceptor concentration reported to date for ZnSe:N epitaxial material grown by molecular beam epitaxy. In addition, light-emitting diodes based on ZnSe:N/ZnSe:Cl, p-n homojunctions have been found to exhibit dominant electroluminescence in the blue region of the visible spectrum at room temperature.

We have carried out the first detailed structural studies of degradation in II-VI blue-green light emitters. Electroluminescence and transmission electron microscopy studies carried out on light emitting diodes fabricated from quantum well laser structures and electroluminescence studies on stripe laser structures show that degradation occurs by the formation and propagation of crystal defects. The studies indicate that room temperature cw lasing in such structures is possibly prevented by the rapid formation of such defects at the high current densities required for lasing.