11,387 research outputs found
Tomography by noise
We present an efficient and robust method for the reconstruction of photon
number distributions by using solely thermal noise as a probe. The method uses
a minimal number of pre-calibrated quantum devices, only one on/off
single-photon detector is sufficient. Feasibility of the method is demonstrated
by the experimental inference of single-photon, thermal and two-photon states.
The method is stable to experimental imperfections and provides a direct,
user-friendly quantum diagnostics tool
X-ray ptychography on low-dimensional hard-condensed matter materials
Tailoring structural, chemical, and electronic (dis-)order in heterogeneous media is one of the transformative opportunities to enable new functionalities and sciences in energy and quantum materials. This endeavor requires elemental, chemical, and magnetic sensitivities at the nano/atomic scale in two- and three-dimensional space. Soft X-ray radiation and hard X-ray radiation provided by synchrotron facilities have emerged as standard characterization probes owing to their inherent element-specificity and high intensity. One of the most promising methods in view of sensitivity and spatial resolution is coherent diffraction imaging, namely, X-ray ptychography, which is envisioned to take on the dominance of electron imaging techniques offering with atomic resolution in the age of diffraction limited light sources. In this review, we discuss the current research examples of far-field diffraction-based X-ray ptychography on two-dimensional and three-dimensional semiconductors, ferroelectrics, and ferromagnets and their blooming future as a mainstream tool for materials sciences
Hall current accelerator Final report, 10 Jun. 1964 - 10 Sep. 1965
Axisymmetric Hall current accelerator as electric spacecraft propulsion syste
Time-Multiplexed Measurements of Nonclassical Light at Telecom Wavelengths
We report the experimental reconstruction of the statistical properties of an
ultrafast pulsed type-II parametric down conversion source in a periodically
poled KTP waveguide at telecom wavelengths, with almost perfect photon-number
correlations. We used a photon-number-resolving time-multiplexed detector based
on a fiber-optical setup and a pair of avalanche photodiodes. By resorting to a
germane data-pattern tomography, we assess the properties of the nonclassical
light states states with unprecedented precision.Comment: 4.5 pages, 5 color figues. Comments welcome
Efficient algorithm for optimizing data pattern tomography
We give a detailed account of an efficient search algorithm for the data
pattern tomography proposed by J. Rehacek, D. Mogilevtsev, and Z. Hradil [Phys.
Rev. Lett.~\textbf{105}, 010402 (2010)], where the quantum state of a system is
reconstructed without a priori knowledge about the measuring setup. The method
is especially suited for experiments involving complex detectors, which are
difficult to calibrate and characterize. We illustrate the approach with the
case study of the homodyne detection of a nonclassical photon state.Comment: 5 pages, 5 eps-color figure
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