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"Everything should be as simple as it is, but not simpler", Albert Einstein
Browsing All posts tagged under »Optics«
Invisibility cloaking in ‘perfect’ demonstration
November 12, 2012
By Jason Palmer Scientists have succeeded in “cloaking” an object perfectly for the first time, rendering a centimetre-scale cylinder invisible to microwaves. Many “invisibility cloak” efforts have been demonstrated, but all have reflected some of the incident light, making the illusion incomplete. A Nature Materials study has now shown how to pull off the trick […]
A Double Green Flash
November 21, 2011
At sunset, the sky is often painted with an array of oranges, reds and yellows, and even some shades of pink. There are, however, occasions when a green flash appears above the solar disc for a second or so. One such occurrence was captured beautifully in this picture taken from Cerro Paranal, a 2600-metre-high mountain […]
Laser Meets Lightning
September 5, 2011
On Thursday 18 August, the sky above the Allgäu Public Observatory in southwestern Bavaria was an amazing sight, with the night lit up by two very different phenomena: one an example of advanced technology, and the other of nature’s dramatic power. As ESO tested the new Wendelstein laser guide star unit by shooting a powerful laser beam […]
A Single Atom as a Mirror of an Optical Cavity
September 3, 2011
By tightly focussing a laser eld onto a single cold ion trapped in front of a far-distant dielectric mirror, we could observe a quantum electrodynamic e ect whereby the ion behaves as the optical mirror of a Fabry-Perot cavity. We show that the amplitude of the laser eld is signi cantly altered due to a modi cation of […]
This cloud has a rainbow lining
September 2, 2011
The multicoloured halo surrounding the peak of this dark cloud looks heavenly, but it’s actually an iridescent pileus cloud, also called a cap cloud. These smooth, round clouds form on top of a puffy cumulus cloud when it rises into higher, colder air. The pileus cloud is made up of uniformly sized water droplets that […]
The dialogue between quantum light and matter
August 31, 2011
The Rabi model (RM) describes the simplest interaction between light and matter. In its semiclassical form, this model describes the coupling of a two-level system and a classical monochromatic field. The fully quantum model considers the same situation, with the light field quantized. Although this model has had an impressive impact on many fields of […]
Gravitational Lensing as a Mechanism For Effective Cloaking
August 20, 2011
Benjamin K. Tippett In light of the surge in popularity of electromagnetic cloaking devices, we consider whether it is possible to use general relativity to cloak a volume of spacetime through gravitational lensing. A metric for such a spacetime geometry is presented, and its geometric and physical implications are explained. In general relativity, there is […]
On the genesis and evolution of Integrated Quantum Optics
August 17, 2011
Applications of Integrated Optics to quantum sources, detectors, interfaces, memories and linear optical quantum computing are described in this review. By their inherent compactness, efficiencies, and interconnectability, many of the demonstrated individual devices can clearly serve as building blocks for more complex quantum systems, that could also profit from the incorporation of other guided wave […]
Researchers Develop Technique for Dynamically Controlling Plasmonic Airy Beams
August 12, 2011
One of the earliest lessons in science that students learn is that a ray or beam of light travels in a straight line. Students also learn that light rays fan out or diffract as they travel. Recently it was discovered that light rays can travel without diffraction in a curved arc in free space. These […]
Some People Talk About Space-Time Invisibility Cloaks. At Cornell, They Built One
July 19, 2011
Demonstrating the world’s first device that creates a hole in time We’ve written previously about the theoretical possibility of “event cloaks”–metamaterial space-time devices that could theoretically conceal an entire event in time from the view of an outsider. Well, while some bright minds were just talking about bending space-time to their whims, a team at […]
December 26, 2012
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