20 research outputs found
Large Scale Daily Contacts and Mobility Model - an Individual-Based Countrywide Simulation Study for Poland
In this study we describe a simulation platform used to create a virtual society of Poland, with a particular emphasis on contact patterns arising from daily commuting to schools or workplaces. In order to reproduce the map of contacts, we are using a geo-referenced Agent Based Model. Within this framework, we propose a set of different stochastic algorithms, utilizing available aggregated census data. Based on this model system, we present selected statistical analysis, such as the accessibility of schools or the location of rescue service units. This platform will serve as a base for further large scale epidemiological and transportation simulation studies. However, the first approach to a simple, country-wide transportation model is also presented here. The application scope of the platform extends beyond the simulations of epidemic or transportation, and pertains to any situation where there are no easily available means, other than computer simulations, to conduct large scale investigations of complex population dynamics.Agent Based Model, Educational Availability, Daily Commuting, Social Network, Virtual Society Simulations
Low-power, 10-Gbps 1.5-Vpp differential CMOS driver for a silicon electro-optic ring modulator
We present a novel driver circuit enabling electro-optic modulation with high extinction ratio from a co-designed silicon ring modulator. The driver circuit provides an asymmetric differential output at 10Gbps with a voltage swing up to 1.5V(pp) from a single 1.0V supply, maximizing the resonance-wavelength shift of depletion-type ring modulators while avoiding carrier injection. A test chip containing 4 reconfigurable driver circuits was fabricated in 40nm CMOS technology. The measured energy consumption for driving a 100fF capacitive load at 10Gbps was as low as 125fJ/bit and 220fJ/bit at 1V(pp) and 1.5V(pp) respectively. After flip-chip integration with ring modulators on a silicon-photonics chip, the power consumption was measured to be 210fJ/bit and 350fJ/bit respectively
O-Band Subwavelength Grating Filters in a Monolithic Photonics Technology
The data communications industry has begun transitioning from electrical to
optical interconnects in datacenters in order to overcome performance
bottlenecks and meet consumer needs. To mitigate the costs associated with this
change and achieve performance for 5G and beyond, it is crucial to explore
advanced photonic devices that can enable high-bandwidth interconnects via
wavelength-division multiplexing (WDM) in photonic integrated circuits.
Subwavelength grating (SWG) filters have shown great promise for WDM
applications. However, the small feature sizes necessary to implement these
structures have prohibited them from penetrating into industrial applications.
To explore the manufacturability and performance of SWG filters in an
industrial setting, we fabricate and characterize O-band subwavelength grating
filters using the monolithic photonics technology at GLOBALFOUNDRIES (GF). We
demonstrate a low drop channel loss of -1.2 dB with a flat-top response, a high
extinction ratio of -30 dB, a 3 dB channel width of 5 nm and single-source
thermal tunability without shape distortion. This filter structure was designed
using elements from the product design kit provided by GF and functions in a
compact footprint of 0.002 mm2 with a minimum feature size of 150 nm.Comment: 4 pages, 3 figure
Hierarchical Analysis of Short Defects between Metal Lines in CMOS IC
Abstract Current paper proposes a new hierarchical approach to defect-oriented testing of CMOS circuit
Wavelenght Locking of a Si Ring Modulator using an Integrated Drop-Port OMA Monitoring Circuit
© 2015 IEEE. We demonstrate wavelength locking of a hybrid C MOS-silicon photonics ring-based transmitter through direct monitoring of the optical modulation amplitude (OMA) at the drop port of the ring modulator. The OMA is read from a Ge photodetector by a low-power 40nm CMOS circuit, which subsequently drives a feed-back loop that controls the modulator temperature using an integrated heater. OMA stabilization is demonstrated under abrupt laser wavelength variations of up to 150pm, under dynamic modulation at 2Gb/s.status: publishe
Advances in silicon photonics WDM devices
System performance scaling imposes an increase of package-to-package aggregate bandwidths to interface chips in high performance computing. This scaling is expected to encounter several I/O bottlenecks (pin count, speed, power consumption) when implemented in the electrical domain. Several optical interface technologies are being proposed among which silicon photonics, considered as a promising candidate. In this paper we will review the recent progress made in this technology that may enable multi-channel WDM links for package-to-package interconnects: 1.0V drivers with microring modulators and compact manufacturable microring filters with efficient thermal tuning