Jeffrey H. Shapiro

Bio: Jeffrey H. Shapiro is an academic researcher from Massachusetts Institute of Technology. The author has contributed to research in topics: Photon & Quantum key distribution. The author has an hindex of 65, co-authored 395 publications receiving 17401 citations.

Random-Medium Propagation Theory Applied To Communication And Radar System Analyses

Abstract: Atmospheric electromagnetic wave propagation plays a crucial role in determining the performance of communication and radar systems that operate at millimeter through visible wave-lengths. Theoretical treatments of atmospheric wave propagation draw upon work on the micrometeorology of the medium, and feed work on the design and performance analysis of communications and radar systems. This paper will illustrate some of the features of the foregoing hierarchy, focusing on the interaction between the propagation and system analyses. Specific examples include: optical communication through atmospheric turbulence, coherent laser radar operation in atmospheric turbulence, and millimeter-wave communication through rain.

Phase-conjugate optical coherence tomography

Abstract: We demonstrate a new type of optical coherence tomography using only classical resources to achieve results that are typically associated with quantum-enhancedmetrology: factor-of-two axial resolution enhancement and even-order dispersion cancellation.

A Flexible Cross-Talk Simulator for Multiple Spatial-Mode Free-Space Optical Communication

Abstract: Laser communication with both high photon information efficiency (many bits/detected-photon) and high spectral efficiency (many bits/sec-Hz) is impossible with a single spatial-mode free-space link. Achieving these high efficiencies in the same system requires operation with 10's to 1000's of high-transmissivity spatial modes. Such systems will likely be restricted to 1 to 10 km line-of-sight terrestrial paths on which turbulence-induced cross talk will be encountered. In this paper we propose a cross-talk simulator for multiple spatial-mode free-space optical communication that could provide valuable information about the relevant merits of different mode sets when they are employed in conjunction with real modal multiplexers and demultiplexers.

Theoretical analysis of quantum ghost imaging through turbulence

Abstract: United States. Defense Advanced Research Projects Agency. System Science Division. Defense Sciences Office (InPho Grant No. W911NF-10-1-0404)

Engineered phase-matching for quantum photonics

Abstract: We demonstrate Gaussian-shaped quasi-phase matching of a nonlinear optical crystal via custom duty-cycle modulation on its grating structure. Our analysis shows this crystal can generate heralded single photons with 97% spectral purity.

I and i

Abstract: There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality. Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

Phd by thesis

Abstract: Deposits of clastic carbonate-dominated (calciclastic) sedimentary slope systems in the rock record have been identified mostly as linearly-consistent carbonate apron deposits, even though most ancient clastic carbonate slope deposits fit the submarine fan systems better. Calciclastic submarine fans are consequently rarely described and are poorly understood. Subsequently, very little is known especially in mud-dominated calciclastic submarine fan systems. Presented in this study are a sedimentological core and petrographic characterisation of samples from eleven boreholes from the Lower Carboniferous of Bowland Basin (Northwest England) that reveals a >250 m thick calciturbidite complex deposited in a calciclastic submarine fan setting. Seven facies are recognised from core and thin section characterisation and are grouped into three carbonate turbidite sequences. They include: 1) Calciturbidites, comprising mostly of highto low-density, wavy-laminated bioclast-rich facies; 2) low-density densite mudstones which are characterised by planar laminated and unlaminated muddominated facies; and 3) Calcidebrites which are muddy or hyper-concentrated debrisflow deposits occurring as poorly-sorted, chaotic, mud-supported floatstones. These

The Observation of Gravitational Waves from a Binary Black Hole Merger

Abstract: On September 14, 2015 at 09:50:45 UTC the two detectors of the Laser Interferometer Gravitational-Wave Observatory simultaneously observed a transient gravitational-wave signal. The signal sweeps upwards in frequency from 35 to 250 Hz with a peak gravitational-wave strain of 1.0×10(-21). It matches the waveform predicted by general relativity for the inspiral and merger of a pair of black holes and the ringdown of the resulting single black hole. The signal was observed with a matched-filter signal-to-noise ratio of 24 and a false alarm rate estimated to be less than 1 event per 203,000 years, equivalent to a significance greater than 5.1σ. The source lies at a luminosity distance of 410(-180)(+160) Mpc corresponding to a redshift z=0.09(-0.04)(+0.03). In the source frame, the initial black hole masses are 36(-4)(+5)M⊙ and 29(-4)(+4)M⊙, and the final black hole mass is 62(-4)(+4)M⊙, with 3.0(-0.5)(+0.5)M⊙c(2) radiated in gravitational waves. All uncertainties define 90% credible intervals. These observations demonstrate the existence of binary stellar-mass black hole systems. This is the first direct detection of gravitational waves and the first observation of a binary black hole merger.

Computer vision : a modern approach = 计算机视觉 : 一种现代的方法

Abstract: From the Publisher: The accessible presentation of this book gives both a general view of the entire computer vision enterprise and also offers sufficient detail to be able to build useful applications. Users learn techniques that have proven to be useful by first-hand experience and a wide range of mathematical methods. A CD-ROM with every copy of the text contains source code for programming practice, color images, and illustrative movies. Comprehensive and up-to-date, this book includes essential topics that either reflect practical significance or are of theoretical importance. Topics are discussed in substantial and increasing depth. Application surveys describe numerous important application areas such as image based rendering and digital libraries. Many important algorithms broken down and illustrated in pseudo code. Appropriate for use by engineers as a comprehensive reference to the computer vision enterprise.

Terabit free-space data transmission employing orbital angular momentum multiplexing

Abstract: Researchers demonstrate the ability to multiplex and transfer data between twisted beams of light with different amounts of orbital angular momentum — a development that provides new opportunities for increasing the data capacity of free-space optical communications links.