11,937 research outputs found
FirstLight: Pluggable Optical Interconnect Technologies for Polymeric Electro-Optical Printed Circuit Boards in Data Centers
The protocol data rate governing data storage devices will increase to over 12 Gb/s by 2013 thereby imposing unmanageable cost and performance burdens on future digital data storage systems. The resulting performance bottleneck can be substantially reduced by conveying high-speed data optically instead of electronically. A novel active pluggable 82.5 Gb/s aggregate bit rate optical connector technology, the design and fabrication of a compact electro-optical printed circuit board to meet exacting specifications, and a method for low cost, high precision, passive optical assembly are presented. A demonstration platform was constructed to assess the viability of embedded electro-optical midplane technology in such systems including the first ever demonstration of a pluggable active optical waveguide printed circuit board connector. High-speed optical data transfer at 10.3125 Gb/s was demonstrated through a complex polymer waveguide interconnect layer embedded into a 262 mm × 240 mm × 4.3 mm electro-optical midplane. Bit error rates of less than 10-12 and optical losses as low as 6 dB were demonstrated through nine multimode polymer wave guides with an aggregate data bandwidth of 92.8125 Gb/s
Gendered Paths to Formal and Informal Resources in Post-Disaster Development in the Ecuadorian Andes
The devastating eruptions of Mount Tungurahua in the Ecuadorian highlands in 1999 and 2006 left many communities struggling to rebuild their homes and others permanently displaced to settlements built by state and nongovernmental organizations. For several years afterward, households diversified their economic strategies to compensate for losses, communities organized to promote local development, and the state and nongovernmental organizations sponsored many economic recovery programs in the affected communities. Our study examined the ways in which gender and gender roles were associated with different levels and paths of access to scarce resources in these communities. Specifically, this article contrasts the experiences of men and women in accessing household necessities and project assistance through formal institutions and informal networks. We found that women and men used different types of informal social support networks, with men receiving significantly more material, emotional, and informational support than women. We also found that men and women experienced different challenges and advantages when pursuing support through local and extralocal institutions and that these institutions often coordinated in ways that reified their biases. We present a methodology that is replicable in a wide variety of disaster, resettlement, and development settings, and we advocate an inductive, evidence-based approach to policy, built upon an understanding of local gender, class, and ethnic dynamics affecting access to formal and informal resources. This evidence should be used to build more robust local institutions that can resist wider social and cultural pressures for male dominance and gendered exclusion
Magnetoelectric Jones Dichroism in Atoms
The authors suggest that atomic experiments measuring the interference
between magnetic-dipole and electric-field-induced electric-dipole transition
amplitudes provide a valuable system to study magnetoelectric Jones effects.Comment: 3 pages, 2 figure
Non-linear and quantum optics of a type II OPO containing a birefringent element Part 1: Classical operation
We describe theoretically the main characteristics of the steady state regime
of a type II Optical Parametric Oscillator (OPO) containing a birefringent
plate. In such a device the signal and idler waves are at the same time
linearly coupled by the plate and nonlinearly coupled by the
crystal. This mixed coupling allows, in some well-defined range of the control
parameters, a frequency degenerate operation as well as phase locking between
the signal and idler modes. We describe here a complete model taking into
account all possible effects in the system, \emph{i.e.} arbitrary rotation of
the waveplate, non perfect phase matching, ring and linear cavities. This model
is able to explain the detailed features of the experiments performed with this
system.Comment: To be published in EPJ
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