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This is the first time that significant pair production has been demonstrated in a structure that can be electrically self-pumped and which can form the basis for passive optical circuitry, bringing us markedly closer to complete integration of quantum optical technologies.

"A light-emitting diode (LED) that emits more light energy than it consumes in electrical energy has been unveiled by researchers in the US. The device - which has a conventional efficiency of greater than 200% - behaves as a kind of optical heat pump that converts lattice vibrations into infrared photons, cooling its surroundings in the process."

Sorry, did not see that you have already posted this one ...

Basis for after next generation processors?

Sante: did you see this?

Maybe a stupid question: The authors argue with the results obtained by Cohen and Glashow [2]. In [2] ist was stated that superluminal neutrinos should lose energy by producing photons and e+e- pairs. This should be observable. These conslusions are based on known physics (I guess), i.e. on the laws valid for subluminal conditions. How reasonable is it to apply (i.e. to assume the validity of) the same laws for superluminal particles?

Weird.

This reminds me a 2013 paper on how to perform derivatives, integrals and even time reversal in optical fibres: http://www.nature.com/srep/2013/130403/srep01594/full/srep01594.html "The manipulation of dynamic Brillouin gratings in optical fibers is demonstrated to be an extremely flexible technique to achieve, with a single experimental setup, several all-optical signal processing functions. In particular, all-optical time differentiation, time integration and true time reversal are theoretically predicted, and then numerically and experimentally demonstrated."

Would this kind of computer be more space environment resistive?

A joint Harvard-MIT research program led by Harvard Professor of Physics Mikhail Lukin and MIT Professor of Physics Vladan Vuletic has created a new state of matter the two describe as extremely similar to the lightsabers seen in "Star Wars."

"Photonic molecules"? Intriguing..

A Heisenberg's dog is the central unit in a quantum computer that factors prime numbers. We report the outcome of a proof-of-principle Gedankenexperiment in which the number 3 was factored and good agreement was found both with an analytical theoretical prediction and with the results of a quantum Las Vegas calculation. Other future applications of Heisenberg's dog are hinted at. The anonymous reports of the referees and our reply to them are reproduced in appendix A and appendix B respectively.

Chemists at UCR have found a way of turning a single photon into two excitons, by a process known as singlet fission. By doubling the yield of excitons in a solar cell, you theoretically double the number of electrons produced and could lead to having a max theoretical efficiency of 60% or more in an (organic) solar cell See also DOI: 10.1021/jz500676c - "Singlet Fission: From Coherences to Kinetics"

Imagine a material that only admits thermal conduction for certain temperatures. Martin Maldovan from Georgia Tech holds a tiny thermoelectric device that turns cold on one side when current is applied. Recent research has focused on the possibility of using interference effects in phonon waves to control heat transport in materials. These are exciting news (see Nature Materials paper here http://www.nature.com/nmat/journal/v14/n7/full/nmat4308.html). Heterostructure research lead to outstanding new possibilities when applied to electronic transport (e.g. in quantum well and quantum dots) and to photonics (e.g. Quantum Cascade Laser tunnable lasers). Apparently the time has come to see selective thermal control in this way! Truly exciting!!

Octopus and optoelectronics camouflage, light bugs and LEDs, or spider webs and touch screens, ... a whole cool bunch of biomimetic stuff

See also the referred work "Light-extraction enhancement for light-emitting diodes: a firefly-inspired structure refined by the genetic algorithm" - quite cool! https://pure.fundp.ac.be/portal/files/11946897/paper89.pdf

interesting chinese paper ...

beam me up scottie!!

terahertz lasers controling the spin of electrons ....

I am so proud to have posted this days before Pacome has spotted it :-)

Very interesting work, showing that apparently algae mastered quantum coherence a few years before us... Inspiring for a new type of light-sensitive devices, and perhaps other applications...

Graphene miracles

Actually since this graphene hype started, being more or less a physics laic, I keep wondering how much of these promised miracles will in fact be delivered? Any chance for an expert's opinion?

very bad article, but nice experiment :)

Here, we show that fluorescent proteins4, 5 in cells are a viable gain medium for optical amplification, and report the first successful realization of biological cell lasers based on green fluorescent protein (GFP).

anything happening on this since 3 years?

yes it seems like. most of it seems however directed toward understanding this effect, and not toward applications. But i'm still convinced that we could find many very interesting applications !!! a few references from ADS: 1 2011PhRvA..83f3807B 1.000 06/2011 A E X R C U Brida, G.; Chekhova, M. V.; Fornaro, G. A.; Genovese, M.; Lopaeva, E. D.; Berchera, I. Ruo Systematic analysis of signal-to-noise ratio in bipartite ghost imaging with classical and quantum light 2 2011PhRvA..83e3808L 1.000 05/2011 A E R U Liu, Ying-Chuan; Kuang, Le-Man Theoretical scheme of thermal-light many-ghost imaging by Nth-order intensity correlation 3 2011PhRvA..83e1803D 1.000 05/2011 A E R C U Dixon, P. Ben; Howland, Gregory A.; Chan, Kam Wai Clifford; O'Sullivan-Hale, Colin; Rodenburg, Brandon; Hardy, Nicholas D.; Shapiro, Jeffrey H.; Simon, D. S.; Sergienko, A. V.; Boyd, R. W.; Howell, John C. Quantum ghost imaging through turbulence 4 2011SPIE.7961E.160O 1.000 03/2011 A E T Ohuchi, H.; Kondo, Y. Complete erasing of ghost images caused by deeply trapped electrons on computed radiography plates 5 2011ApPhL..98k1115M 1.000 03/2011 A E R U Meyers, Ronald E.; Deacon, Keith S.; Shih, Yanhua Turbulence-free ghost imaging 6 2011ApPhL..98k1102G 1.000 03/2011 A E R C U Gan, Shu; Zhang, Su-Heng; Zhao, Ting; Xiong, Jun; Zhang, Xiangdong; Wang, Kaige Cloaking of a phase object in ghost imaging 7 2011RScI...82b3110Y 1.000 02/2011 A E R U Yang, Hao; Zhao, Baosheng; Qiu