Digital data transmission using electro-optically modulated vertical-cavity surface-emitting laser with saturable absorber

An electro-optically (EO) modulated oxide-confined vertical-cavity surface-emitting laser (VCSEL) containing a saturable absorber in the VCSEL cavity is studied. The device contains an EO modulator section that is resonant with the VCSEL cavity. A type-II EO superlattice medium is employed in the modulator section and shown to result in a strong negative EO effect in weak electric fields. Applying the reverse bias voltages to the EO section allows triggering of short pulses in the device. Digital data transmission (return-to-zero pseudo-random bit sequence, 27-1) at 10Gb/s at bit-error-rates well below 10-9 is demonstrated. © 2014 AIP Publishing LLC

Understanding intermediate-band solar cells

The intermediate-band solar cell is designed to provide a large photogenerated current while maintaining a high output voltage. To make this possible, these cells incorporate an energy band that is partially filled with electrons within the forbidden bandgap of a semiconductor. Photons with insufficient energy to pump electrons from the valence band to the conduction band can use this intermediate band as a stepping stone to generate an electron–hole pair. Nanostructured materials and certain alloys have been employed in the practical implementation of intermediate-band solar cells, although challenges still remain for realizing practical devices. Here we offer our present understanding of intermediate-band solar cells, as well as a review of the different approaches pursed for their practical implementation. We also discuss how best to resolve the remaining technical issues

The role of integrated interventions in psychosomatic diseases

Based on the evidence that there can be no health without mental health, psychosomatic medicine recognizes the complexity of the interface between psychiatry, lifestyle and medicine. At the clinical level, psychosomatic medicine integrates interdisciplinary evaluation and management involving diverse specialties including psychiatry, psychology, neurology, internal medicine, allergology, dermatology, rheumatology and endocrinology. At the research level, the fields of psychoneuroimmunology and psychoneuroendocrinology integrate findings from neuroscience, experimental psychology, physiology, genetics, pharmacology and molecular biology to understand the mechanistic underpinnings of psychosomatics. A clinical approach based on personalized and scientifically based integrated interventions, consistent with the bio-psycho-social model of medicine, is the best way to actually promote clinically significant physical and mental health improvements