Simultaneous pulse compression and jitter reduction at 10GHz using novel self-seeding gain-switched DFB laser incorporating a DILM

A novel scheme using a 10 GHz gain-switched DFB laser with simultaneous pulse width and jitter compression allows generation of 380fs pulses with both system limited 150fs jitter and 30 dB extinction ratio. ©1999 Optical Society of America.

Compression and tensile properties of self-reinforced poly(ethylene terephthalate)-composites

Tensile and compression properties of self-reinforced poly(ethylene terephthalate) (SrPET) composites has been investigated. SrPET composites or all-polymer composites have improved mechanical properties compared to the bulk polymer but with maintained recyclability. In contrast to traditional carbon/glass fibre reinforced composites, SrPET composites are very ductile, resulting in high failure strains without softening or catastrophic failure. In tension, the SrPET composites behave linear elastically until the fibre-matrix interface fails, at which point the stiffness starts decreasing. As the material is further strained, strain hardening occurs and the specimen finally fails at a global strain above 10%. In compression, the composite initially fails through fibre yielding, and at higher strains through fibre bending. The stress-strain response is reminiscent of an elastic-perfectly plastic material with a high strain to failure (typically over 10%). This indicates that SrPET composites are not only candidates as semi-structural composites but also as highly efficient energy absorbing materials. © 2012 Elsevier Ltd. All rights reserved.

Self-healing of fractured GaAs nanowires.

In-situ deformation experiments were carried out in a transmission electron microscope to investigate the structural response of single crystal GaAs nanowires (NWs) under compression. A repeatable self-healing process was discovered in which a partially fractured GaAs NW restored its original single crystal structure immediately after an external compressive force was removed. Possible mechanisms of the self-healing process are discussed.