Investigation of the RTN Distribution of nanoscale MOS devices from subthreshold to on-state

This letter presents a numerical investigation of the statistical distribution of the random telegraph noise (RTN) amplitude in nanoscale MOS devices, focusing on the change of its main features when moving from the subthreshold to the on-state conduction regime. Results show that while the distribution can be well approximated by an exponential behavior in subthreshold, large deviations from this behavior appear when moving toward the on-state regime, despite a low probability exponential tail at high RTN amplitudes being preserved. The average value of the distribution is shown to keep an inverse proportionality to channel area, while the slope of the high-amplitude exponential tail changes its dependence on device width, length, and doping when moving from subthreshold to on-state

Fundamental Power Limits of SAR and ΔΣ Analog-to-Digital Converters

This work aims at estimating and comparing the power limits of ΔΣ and charge-redistribution successiveapproximation register (CR-SAR) analog-to-digital converters (ADCs), in order to identify which topology is the most powerefficient for a target resolution. A power consumption model for mismatch-limited SAR ADCs and for discrete-time (DT) ΔΣ modulators is presented and validated against experimental data. SAR ADCs are found to be the best choice for low-to-medium resolutions, up to roughly 80 dB of dynamic range (DR). At high resolutions, on the other hand, ΔΣ modulators become more power-efficient. This is due to the intrinsic robustness of the ΔΣ modulation principle against circuit imperfections and nonidealities. Furthermore, a comparison of the area occupation of such topologies reveals that, at high resolutions and for a given dynamic range, ΔΣ ADCs result more area-efficient as well

Possible link between Hashimoto's thyroiditis and oral lichen planus: a novel association found

none5Lo Muzio L.; Santarelli A.; Campisi G.; Lacaita MG.; Favia G.Lo Muzio, L.; Santarelli, Andrea; Campisi, G.; Lacaita, M. G.; Favia, G

GHz QKD at telecom wavelengths using up-conversion detectors

We have developed a hybrid single photon detection scheme for telecom wavelengths based on nonlinear sum-frequency generation and silicon single-photon avalanche diodes (SPADs). The SPAD devices employed have been designed to have very narrow temporal response, i.e. low jitter, which we can exploit for increasing the allowable bit rate for quantum key distribution. The wavelength conversion is obtained using periodically poled Lithium niobate waveguides (W/Gs). The inherently high efficiency of these W/Gs allows us to use a continuous wave laser to seed the nonlinear conversion so as to have a continuous detection scheme. We also present a 1.27GHz qubit repetition rate, one-way phase encoding, quantum key distribution experiment operating at telecom wavelengths that takes advantage of this detection scheme. The proof of principle experiment shows a system capable of MHz raw count rates with a QBER less than 2% and estimated secure key rates greater than 100 kbit/s over 25 km.Comment: 12 pages, 7 figure

Reduced Deadtime and Higher Rate Photon-Counting Detection using a Multiplexed Detector Array

We present a scheme for a photon-counting detection system that can be operated at incident photon rates higher than otherwise possible by suppressing the effects of detector deadtime. The method uses an array of N detectors and a 1-by-N optical switch with a control circuit to direct input light to live detectors. Our calculations and models highlight the advantages of the technique. In particular, using this scheme, a group of N detectors provides an improvement in operation rate that can exceed the improvement that would be obtained by a single detector with deadtime reduced by 1/N, even if it were feasible to produce a single detector with such a large improvement in deadtime. We model the system for continuous and pulsed light sources, both of which are important for quantum metrology and quantum key distribution applications.Comment: 6 figure

Long-distance Bell-type tests using energy-time entangled photons

Long-distance Bell-type experiments are presented. The different experimental challenges and their solutions in order to maintain the strong quantum correlations between energy-time entangled photons over more than 10 km are reported and the results analyzed from the point of view of tests of fundamental physics as well as from the more applied side of quantum communication, specially quantum key distribution. Tests using more than one analyzer on each side are also presented.Comment: 22 pages including 7 figures and 5 table

Quantum Cryptography

Quantum cryptography could well be the first application of quantum mechanics at the individual quanta level. The very fast progress in both theory and experiments over the recent years are reviewed, with emphasis on open questions and technological issues.Comment: 55 pages, 32 figures; to appear in Reviews of Modern Physic

The health determinants in young children: Testing a new surveillance system in Italy

In recent years, the scientific community has stressed the need to invest in the first 1,000 days of life - the time spanning between conception and the 2nd birthday - because it is during this period that the foundations of health are laid and whose effects will be present throughout the life and may influence the next generation. Taking this into account, in 2013 the National Centre for Disease Prevention and Control (CCM) of the Italian Ministry of Health promoted and financed a project to test a surveillance system of the main determinants of health concerning the child between the conception period and the 2nd years of life which are included in the National Programme “GenitoriPiù”: folic acid before and during pregnancy, abstention from tobacco and alcohol during pregnancy and lactation, breastfeeding, infant sleep position, vaccination attitude, and early reading. The Project, started in January 2014 and ended in August 2016, has piloted the design, testing, and evaluation of the surveillance system with the view to national extension and the repeatability over time. The surveillance system has been designed to collect data through a questionnaire compiled by mothers in vaccination centres, in order to produce indicators which will enable territorial and intertempo-ral comparisons to be made. The project has shown the feasibility of this system, identifying favourable conditions and possible difficulties, and its ability to collect important information on children's health

Application of Silicon Photomultipliers to Positron Emission Tomography

Historically, positron emission tomography (PET) systems have been based on scintillation crystals coupled to photomultipliers tubes (PMTs). However, the limited quantum efficiency, bulkiness, and relatively high cost per unit surface area of PMTs, along with the growth of new applications for PET, offers opportunities for other photodetectors. Among these, small-animal scanners, hybrid PET/MRI systems, and incorporation of time-of-flight information are of particular interest and require low-cost, compact, fast, and magnetic field compatible photodetectors. With high quantum efficiency and compact structure, avalanche photodiodes (APDs) overcome several of the drawbacks of PMTs, but this is offset by degraded signal-to-noise and timing properties. Silicon photomultipliers (SiPMs) offer an alternative solution, combining many of the advantages of PMTs and APDs. They have high gain, excellent timing properties and are insensitive to magnetic fields. At the present time, SiPM technology is rapidly developing and therefore an investigation into optimal design and operating conditions is underway together with detailed characterization of SiPM-based PET detectors. Published data are extremely promising and show good energy and timing resolution, as well as the ability to decode small scintillator arrays. SiPMs clearly have the potential to be the photodetector of choice for some, or even perhaps most, PET systems

Physics and Performance of Phase Change Memories

Abstract -Phase change memories (PCM) are considered promising candidates for the replacement of non-volatile Flash technology at the nanoscale. The paper reviews the physics of PCM operation, the scaling potentials of these devices, some options recently proposed for the cell structure, the main challenges for the PCM to become fully competitive with standard Flash technology