114 research outputs found
Ultracompact monolithic integration of balanced, polarization diversity photodetectors for coherent lightwave receivers
The authors have monolithically integrated an optical front-end on InP for balanced, polarization-diversity coherent lightwave reception which is only 1.3-mm long. Low on-chip insertion loss (<4.5 dB) and balanced photoresponse (1.05:1 or better) are achieved at 1.5-μm wavelength using straightforward, regrowth-free fabrication. Low-capacitance photodetectors (≤0.15 pF) are employed for high bandwidth operation
Low-loss, Ultra-compact Monolithic Integration Of High-speed Polarization-diversity Photodetectors
Polarization-selective optical devices are required for polarization-diversity coherent lightwave receivers.[l] Monolithic integration of such devices with photodetectors improves detector functionality and eliminates package complexity by reducing part count and hybrid optical interconnects. Compatibility with high III-V materials' cost, however, requires simple, high-yield processes and compact device size. We previously proposed a simple and compact integration scheme employing metal-loaded vertical couplers for polarization splitting and vertically-coupled photodiodes for O/E conversion. Initial experiments using InGaAsP/InP demonstrated satisfactory optical functionality, with 10.6 and 16dB polarization selectivity for TE and TM polarized-light.[2] Here we show how such integrated devices can be modified to achieve suitable electronic performance, including wide bandwidth and high quantum efficiency
The effects of non-universal extra dimensions on the radiative lepton flavor decays \mu\to e\gamma and \tau\to \mu\gamma in the two Higgs doublet model
We study the effect of non-universal extra dimensions on the branching ratios
of the lepton flavor violating processes \mu\to e\gamma and \tau\to \mu\gamma
in the general two Higgs doublet model. We observe that these effects are small
for a single extra dimension, however, in the case of two extra dimensions
there is a considerable enhancement in the additional contributions.Comment: 16 Pages, 9 Figure
Treatment challenges in and outside a specialist network setting: Pancreatic neuroendocrine tumours
Pancreatic Neuroendocrine Neoplasms comprise a group of rare tumours with special biology, an often indolent behaviour and particular diagnostic and therapeutic requirements. The specialized biochemical tests and radiological investigations, the complexity of surgical options and the variety of medical treatments that require individual tailoring, mandate a multidisciplinary approach that can be optimally achieved through an organized network. The present study describes currents concepts in the management of these tumours as well as an insight into the challenges of delivering the pathway in and outside a Network
- …