3,978 research outputs found
Fast and High-Fidelity Entangling Gate through Parametrically Modulated Longitudinal Coupling
We investigate an approach to universal quantum computation based on the
modulation of longitudinal qubit-oscillator coupling. We show how to realize a
controlled-phase gate by simultaneously modulating the longitudinal coupling of
two qubits to a common oscillator mode. In contrast to the more familiar
transversal qubit-oscillator coupling, the magnitude of the effective
qubit-qubit interaction does not rely on a small perturbative parameter. As a
result, this effective interaction strength can be made large, leading to short
gate times and high gate fidelities. We moreover show how the gate infidelity
can be exponentially suppressed with squeezing and how the entangling gate can
be generalized to qubits coupled to separate oscillators. Our proposal can be
realized in multiple physical platforms for quantum computing, including
superconducting and spin qubits.Comment: 5 pages, 3 figures, Supplemental Materia
The Effects of the Learning-Focused Schools Model on Student Achievement in Math and Reading and Teachers\u27 Perceptions of the Model
Learning-Focused Schools (LFS) is a research-based comprehensive school reform model designed to assist systems, schools, and teachers in using exemplary practices to increase learning and achievement. The purpose of the study was to analyze the first-year implementation of the model and determine its effect on the academic achievement in reading and math of fourth and fifth grade students. Student achievement data was obtained from the Pennsylvania System of School Assessment (PSSA). Using data from the 2008 PSSA, the study compared achievement of students taught by teachers with formal training in the model with achievement of students taught by teachers with no formal training. The study also compared the 2008 PSSA scores and 2007 PSSA scores for both fourth and fifth grade samples. The study also analyzed and discussed survey data collected by the school district. The survey solicited teacher feedback on instructional strategies, planning time, formal training, and administrative support. The only significant finding from the study was increased reading achievement from the experimental group of fifth grade students taught by teachers with formal training in the model. Information from the survey provided evidence to support a successful first-year implementation of the model. A high percentage of teachers implemented expected strategies, met expectations for planning time, and reported adequate support from their building principals. In summary, the purpose for this dissertation topic was to provide the research school district and other districts with information that may guide future decisions for expanded implementation of the Learning-Focused Schools model. Information from the survey information may also assist in implementing effective further professional development necessary to sustain the model
A 10-bits pipeline ADC dedicated to the VFE Electronics of Si-W Ecal
International audienc
Midcourse maneuver operations program
Midcourse Maneuver Operations Program /MMOP/ computes the required velocity change to correct a spacecraft trajectory. The program establishes the existence of maneuvers which satisfy spacecraft constraints, explores alternate trajectories in the event that some out-of-tolerance condition forces a change in plans, and codes the maneuvers into commands
PACS and SPIRE range spectroscopy of cool, evolved stars
Context: At the end of their lives AGB stars are prolific producers of dust
and gas. The details of this mass-loss process are still not understood very
well. Herschel PACS and SPIRE spectra offer a unique way of investigating
properties of AGB stars in general and the mass-loss process in particular.
Methods: The HIPE software with the latest calibration is used to process the
available PACS and SPIRE spectra of 40 evolved stars. The spectra are convolved
with the response curves of the PACS and SPIRE bolometers and compared to the
fluxes measured in imaging data of these sources. Custom software is used to
identify lines in the spectra, and to determine the central wavelengths and
line intensities. Standard molecular line databases are used to associate the
observed lines. Because of the limited spectral resolution of the spectrometers
several known lines are typically potential counterparts to any observed line.
To help identifications the relative contributions in line intensity of the
potential counterpart lines are listed for three characteristic temperatures
based on LTE calculations and assuming optically thin emission. Result: The
following data products are released: the reduced spectra, the lines that are
measured in the spectra with wavelength, intensity, potential identifications,
and the continuum spectra, i.e. the full spectra with all identified lines
removed. As simple examples of how this data can be used in future studies we
have fitted the continuum spectra with three power laws and find that the few
OH/IR stars seem to have significantly steeper slopes than the other oxygen-
and carbon-rich objects in the sample. As another example we constructed
rotational diagrams for CO and fitted a two-component model to derive
rotational temperatures.Comment: A&A accepte
Wolf-Rayets in IC10: Probing the Nearest Starburst
IC10 is the nearest starburst galaxy, as revealed both by its Halpha surface
brightness and the large number of Wolf-Rayet stars (WRs) per unit area. The
relative number of known WC- to WN-type WRs has been thought to be unusually
high (~2), unexpected for IC10's metallicity. In this Letter we report the
first results of a new and deeper survey for WRs in IC10. We sucessfully
detected all of the spectroscopically known WRs, and based upon comparisons
with a neighboring control field, estimate that the total number of WRs in IC10
is about 100. We present spectroscopic confirmation of two of our WR
candidates, both of which are of WN type. Our photometric survey predicts that
the actual WC/WN ratio is ~0.3. This makes the WC/WN ratio of IC 10 consistent
with that expected for its metallicity, but greatly increases the already
unusually high number of WRs, resulting in a surface density that is about 20
times higher than in the LMC. If the majority of these candidates are
spectroscopically confirmed, IC10 must have an exceptional population of high
mass stars.Comment: Accepted by ApJL; only minor correction in this versio
Front-End Electronics of the ALICE dimuon trigger
This document presents the design and performance of the Front-End Electronics (FEE) developed for the ALICE dimuon trigger operating with Resistive Plate Chambers (RPCs) in streamer mode. This electronics, yet ready for production, is based on a dedicated ASIC designed at LPC Clermont-Fd
- …