A solid case of entanglement

For the first time, physicists have convincingly demonstrated that physically separated particles in solid-state devices can be quantum-mechanically entangled. The achievement is analogous to the quantum entanglement of light, except that it involves particles in circuitry instead of photons in optical systems. Both optical and solid-state entanglement offer potential routes to quantum computing and secure communications, but solid-state versions may ultimately be easier to incorporate into electronic devices.

The quest for dilute ferromagnetism in semiconductors: Guides and misguides by theory

A material that exhibits both ferromagnetic and semiconductor properties offers the exciting prospect of combining nonvolatile magnetic storage and conventional semiconductor electronics in a single device. Magnetic semiconductors offer a number of interesting possibilities in the pursuit of  spintronics , a branch of science and technology that exploits the spin dimension of the electron in addition to its charge, for novel electronic devices. These materials combine the properties of a semiconductor and a magnetic material, providing, for instance, a way to create 100 % spin-polarized currents, and by the same token, the promise of electrical control of magnetic effects. While in some magnetic semiconductors, for example, magnetite, all of the material’s constituent ions are intrinsically magnetic (  concentrated magnets  ), the most recent focus has been on nonmagnetic semiconductor host materials that can be doped by a small amount of magnetic transition-metal ions or by defects that promote magnetism (  dilute magnets  ).

Topological insulators: Star material

 A topological insulator sounds simple enough:  A block of material that lets electrons move along its surface, but not through its inside . In fact, it is far from straightforward. Ordinary metals conduct electrons all the way through, whereas ordinary insulators don't conduct electrons at all. A copper-plated block of wood conducts only on the surface, but that is two materials, not one. The idea of a topological insulator is so strange that for a long time, physicists had no reason to believe that such a material would exist .

 Researchers also believe that the collective motions of electrons inside topological insulators will mimic several of the never-before-seen particles predicted by high-energy physicists. Among them are axions, hypothetical particles predicted in the 1970s; magnetic monopoles, single points of north and south magnetism; and Majorana particles — massless, chargeless entities that can serve as their own antiparticles. 

Could some entangled states be useless for quantum cryptography ?

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One of the widely accepted properties of quantum entanglement is secrecy. Since scientists and researchers began working with quantum key distribution, entanglement has been considered an essential part of keeping communications private. What if entanglement didn't always mean secrecy, though ? New work is shedding light on the nature of entanglement and quantum key distribution -  and possibly proving that a high degree of entanglement does not necessarily lead to complete secrecy .

Math behind Internet encryption wins top award: Abel prize awarded to number theorist John Tate

The Abel prize--considered the "Nobel" prize of mathematics--has been awarded to John Tate, recently retired from the University of Texas at Austin, for his work on algebraic number theory, the mathematical discipline that deals with connections between whole numbers and lies at the heart of Internet security.
Established in 2002, the Abel Prize is presented annually by the King of Norway and carries a cash award of $1 million.

Ian Stewart:  Try to find the prime factors of a 200-digit number with pencil and paper--or even with a computer program--and it would take longer than the age of the Universe .

John Tate Biography in Wikipedia

Electrical properties of glass at the nanoscale lead to a pump the size of a red blood cell

Researchers have devised a way to fabricate tiny electrodes from glass, harnessing a phenomenon by which nanoscale glass walls can be transformed from insulators to conductors and back again. At larger scales, that phenomenon, known as  dielectric breakdown , leads to excess heating and structural damage,  but at the nanoscale the process appears to be harmless and  reversible.

CSS3 Examples and Code

We present a set of CSS3 examples which include the state of art in web design. Simple code for the examples are included.
 
http://fisica.ciens.ucv.ve/felix/css3/

Graphene transistor could advance nanodevices

For years, scientists and researchers have been looking into the properties of carbon nanotubes and graphene for use in nanoelectronics.  There is no real mass application of devices based on graphene and carbon nanotubes , Zhenxing Wang tells PhysOrg.com.  This is really an opportunity for them to show their capabilities .

Appl. Phys. Lett. 96, 173104 ( 2010 )

Death of a star in 3D

( PhysOrg.com ) -- Researchers at the Max Planck Institute for Astrophysics in Garching have for the first time managed to reproduce the asymmetries and fast-moving iron clumps of observed supernovae by complex computer simulations in all three dimensions. To this end they successfully followed the outburst in their models consistently from milliseconds after the onset of the blast to the demise of the star several hours later. ( Astrophysical Journal, May 10th, 2010 ).

Unraveling the physics of DNA's double helix

 The stability of DNA is so fundamental to life that it's important to understand all factors , said Piotr Marszalek, a professor of mechanical engineering and materials sciences at Duke.  If you want to create accurate models of DNA to study its interaction with proteins or drugs, for example,  you need to understand the basic physics of the molecule . For that, you need solid measurements of the forces that stabilize DNA .

DNA construction kit for nanoengines

For a rotaxane molecule consists essentially of an axle and a ring, or hoop, threaded over it. To prevent the hoop from slipping off the axle, bulky  stoppers  are placed at each end. These, in turn, consist of intertwined rings. The whole construction looks rather like a dumbbell with a hoop around its handle ( see diagram ).

Laser technology provides a quantum leap (La tecnología láser da un salto cuántico)

En la Universidad de Innsbruck ( Austria ), un equipo de investigación financiado con fondos comunitarios ha creado un láser de átomo único que se rige por el mismo principio que los láseres clásicos pero que además presenta propiedades cuánticas en sus interacciones entre átomos y fotones. Los resultados de su investigación, publicados en la revista Nature Physics, ampliarán el conocimiento que se posee de las propiedades de los láseres y podrán utilizarse para medir composiciones de oligoelementos gaseosos e isótopos de carbono en el aire y el suelo.

At the University of Innsbruck ( Austria ), a team of private funded research has created a single atom laser which is governed by the same principle as lasers but also presents classical quantum properties in interactions between atoms and photons. The results of their research, published in the journal Nature Physics, expand the knowledge of the lasers properties and may be used to measure gas compositions of trace elements and isotopes of carbon in the air and soil.

La mayor tormenta solar en 500 días inquieta a los científicos

Una vez más, y esta vez con más fuerza y de forma totalmente inesperada, el Sol ha dado muestras de que ha despertado de su letargo. El telescopio espacial 'Tesis' registró el lunes la mayor tormenta geomagnética desde octubre de 2008, según informa el Instituto ruso de Física 'Lebedev'. La tormenta solar alcanzó el nivel 7 en una escala de 10, el máximo histórico del último año y medio. Su fase activa se prolongó de las 10.00 a las 19.00 horas. "No se han producido fluctuaciones de tal magnitud durante 540 días, desde el 11 de octubre de 2008", aseguran los técnicos. Una gran actividad solar no presagia nada bueno en un mundo absolutamente dependiente de la tecnología.

Once again, this time harder and quite unexpectedly, the Sun has shown that he has awakened from its slumber. The Hubble Space 'thesis' posted on Monday, the largest geomagnetic storm of October 2008, according to the Russian Institute of Physics 'Lebedev'. The solar storm reached level 7 on a scale of 10, the record high last year and a half. Active phase lasted from 10.00 to 19.00. "There have been no fluctuations of such magnitude for 540 days, from October 11, 2008", say the technicians. A high solar activity does not bode well in a world utterly dependent on technology.

Viajar a la velocidad de la luz mataría en pocos segundos

Malas noticias para todos los que soñábamos con recorrer la galaxia a velocidades relativísticas. Según parece, al desplazarnos a velocidades cercanas a la de la luz, los escasos átomos de hidrógeno que existen en el espacio  vacío  nos golpearían tan duro como las partículas aceleradas por el Gran Colisionador de Hadrones ( LHC ). Si los científicos de la Universidad Johns Hopkins están en lo cierto,  esos pequeños átomos nos freirían en pocos segundos .

Bad news for all those who dreamed of exploring the galaxy at relativistic speeds. Apparently, the motion at speeds approaching that of light, the few hydrogen atoms that exist in the  vacuum  would hit us as hard as particles accelerated by the Large Hadron Collider ( LHC ). If scientists at Johns Hopkins University are right,  these little atoms will fry us in a few seconds .

Charging Ahead: Carbon Nanotubes Could Hold Long-Sought Battery Technology Breakthrough

With battery technology advances long overdue, researchers are racing to develop more efficient ways to store power. One hopeful option is in the use of carbon nanotubes,  which can store much more electricity by weight than lithium-ion batteries while keeping their charge and remain durable for far longer .

Light Improvement: Could Quantum Dots Boost the Quality of Cell Phone Pix?

Semiconductor crystals known as quantum dots have long held the promise of improving solar cells, lasers and lighting fixtures, but the reality is that integrating these fluorescent nanoparticles into existing technologies has proved difficult. One Silicon Valley start-up now aims to change this by the end of next year using quantum dots to vastly improve the picture-taking quality of cell phone cameras.

Scanner scans a 200 page book in one minute (w/ Video)

A research team led by Professor Masatoshi Ishikawa of the University of Tokyo has developed a prototype scanner that allows users to scan a book simply by rapidly flipping its pages. A high-speed camera operating at 500 fps and producing pictures with a resolution of 1280 x 1024 pixels, takes pictures of the page and its contents of text and images under ordinary light. A laser then projects lines on the page, and the camera captures this image as well. The lines allow the system to adjust for the curvature and distortion of pages as they are being flipped, and the software reconstructs the image into a digitized picture of a flat, regular page.

NIST’s Second ‘Quantum Logic Clock’ Based on Aluminum Ion is Now World’s Most Precise Clock

Physicists at the National Institute of Standards and Technology (NIST) have built an enhanced version of an experimental atomic clock based on a single aluminum atom that is now the world’s most precise clock, more than twice as precise as the previous pacesetter based on a mercury atom. The new aluminum clock would neither gain nor lose one second in about 3.7 billion years, according to measurements to be reported in Physical Review Letters ( preprint ). The new clock is the second version of NIST’s  quantum logic clock , so called because it borrows the logical processing used for atoms storing data in experimental quantum computing, another major focus of the same NIST research group. ( The logic process is described at http://www.nist.gov/public_affairs/releases/logic_clock/logic_clock.html#background ) The second version of the logic clock offers more than twice the precision of the original.

Buscan crear super computadoras sin límite de velocidad

Un equipo de investigadores liderados por científicos de la Universidad de Yale ejecutó exitosamente operaciones simples de mecánica cuántica, lo cual podría significar la creación de hardware con potencial ilimitado de procesamiento.

CLIMATE CHANGE IS NATURAL: 100 REASONS WHY

HERE are the 100 reasons, released in a dossier issued by the European Foundation, why climate change is natural and not man-made: 1) There is “no real scientific proof” that the current warming is caused by the rise of greenhouse gases from man’s activity.

Read 99 more reasons at this page link ( above )