Featured
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Letter |
Generation of electron beams carrying orbital angular momentum
Light beams can be engineered to carry orbital angular momentum, with application as, for instance, optical 'spanners' — essentially a 'twisted' variant of the more familiar optical tweezers. Here it is shown that it is, in principle, possible to engineer similar behaviour into an electron beam. Such a beam could find use in a variety of spectroscopy and microscopy techniques.
- Masaya Uchida
- & Akira Tonomura
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Research Highlights |
Photonics: Carbon light catcher
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News |
It's a wrap for bacteria
Atomically thin carbon sheets offer bacteria a protective shell in electron microscopes.
- Geoff Brumfiel
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News |
Galileo backed Copernicus despite data
Stars viewed through early telescopes suggested that Earth stood still.
- Katharine Sanderson
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Letter |
Reinventing germanium avalanche photodetector for nanophotonic on-chip optical interconnects
To integrate microchips with optical communications a photodetector is required to mediate the optical and electronic signals. Although germanium photodetectors are compatible with silicon their performance is impaired by poor intrinsic noise. Here the noise is reduced by nanometre engineering of optical and electrical fields to produce a compact and efficient photodetector.
- Solomon Assefa
- , Fengnian Xia
- & Yurii A. Vlasov
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Research Highlights |
Applied physics: Sound lasers hum along
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News |
'Sasers' set to stun
Sound-based lasers could improve imaging and electronics.
- Geoff Brumfiel
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Letter |
Simultaneous phase and size control of upconversion nanocrystals through lanthanide doping
Many technological materials are intentionally 'doped' with foreign elements to impart new and desirable properties, a classic example being the doping of semiconductors to tune their electronic behaviour. Here lanthanide doping is used to control the growth of nanocrystals, allowing for simultaneous tuning of the size, crystallographic phase and optical properties of the hybrid material.
- Feng Wang
- , Yu Han
- & Xiaogang Liu
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News |
Underwater robot automates ocean testing
'Lab in a can' eliminates the middleman between sample site and lab.
- Richard A. Lovett
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Letter |
A change in the optical polarization associated with a γ-ray flare in the blazar 3C 279
It is widely accepted that strong and variable radiation detected over all accessible energy bands in a number of active galaxies arises from a relativistic, Doppler-boosted jet pointing close to our line of sight. However, the size of the emitting zone and the location of this region relative to the central supermassive black hole are poorly understood. Here, the coincidence of a γ-ray flare with a dramatic change of optical polarization angle is reported, providing evidence for co-spatiality of optical and γ-ray emission regions and indicating a highly ordered jet magnetic field.
- A. A. Abdo
- , M. Ackermann
- & M. Sikora
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News |
General relativity tested on a tabletop
Atomic-clock experiment pins down accuracy of fundamental gravity measurement.
- Eric Hand
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Research Highlights |
Astronomy: Hot spectra
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Research Highlights |
Geophysics: Synthetic sky light
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News Feature |
Smart grids: The energy storage problem
Renewable energy is not a viable option unless energy can be stored on a large scale. David Lindley looks at five ways to do that.
- David Lindley
Telescope arrays give fine view of stars
Silicon whiskers catch rays well