Fishnet cloak of negative refraction based invisibility

Let Me Feel Those Fishnet Hose

NYT and others report Berkeley researchers have used nano wires and fishnet, as described in Nature, to provide a cloak of invisibility. Based on the idea of negative refraction, the materials appear able to bend long-wavelength microwaves. A layered fishnet structure alternating between a metal and magnesium fluoride results in a metamaterial with a negative index of refraction for infrared light. Other Berkeley researchers in an almost concurrent publication in Science paper used a different approach, building an array of minuscule upright wires, which changed the electric fields of passing light waves. These both recall Retro-reflective Projection Technology (RPT) of 2003 from Tachi Lab. Which is maybe unweildy, but is still pretty much composable from off the shelf parts. In conversation with a poet colleague these advances were mentioned as portals perhaps to future powerful fields of poetic chorus. One recalls Gleem’s Invisible Shield too, and worries that Claude Rains’s ghost lurks. Worry Worry Worry.

A Noble Award for IBM magneto-wizard Parkin

In case you missed it, IBM fellow Stuart Parkin was awarded the Daniel E. Noble Award for fundamental contributions to the development of magneto-resistive devices for nonvolatile RAM. These advances greatly enhanced the capabilities of modern disk drives. In recent years Parkin has been prominent in work that led to Racetrack Memory, which uses electron spin, rather than the charge, to create electronic devices. Parkin received the award along with Jim Daughton and Saied Tehrani. The award was announced at the IEEE International Magnetics Conference in Madrid.

HP discovers memristor

H-P’s discovery of the memristor, a fourth circuit type, may mean a new member joins the capacitor, the resistor and the inductor in the pantheon of circuit element types. HP researchers created a working memristor on their way to creating a successful nano-scale crossbar switch. The memristor’s existence had been theorized 37 years ago by UC Berkeley professor Leon Chua.

The thing is a triumph for flux and hysterisis, formulated on titanium dioxide. The memristor will enable a new era of nanoscale electronics, say the scientists.

EETimes’ Colin Johnson went straight to the source with his story on the memristor. He spoke at length with Chua, who postulated the part in a 1971 paper. Chua sees this in grand historical strokes. A sample:

The hold-up over the last 37 years, according to professor Chua, has been a misconception that has pervaded electronic circuit theory. That misconception is that the fundamental relationship in passive circuitry is between voltage and charge. What the researchers contend is that the fundamental relationship is actually between changes-in-voltage, or flux, and charge. Such is the insight that enabled HP to invent the memristor, according to Chua and Williams.

“Electronic theorists have been using the wrong pair of variables all these years — voltage and charge. The missing part of electronic theory was that the fundamental pair of variables is flux and charge,” said Chua. “The situation is analogous to what is called “Aristotle’s Law of Motion, which was wrong, because he said that force must be proportional to velocity. That misled people for 2000 years until Newton came along and pointed out that Aristotle was using the wrong variables. Newton said that force is proportional to acceleration — the change in velocity. This is exactly the situation with electronic circuit theory today. All electronic text books have been teaching using the wrong variables — voltage and charge–explaining away inaccuracies as anomalies.
The hold-up over the last 37 years, according to professor Chua, has been a misconception that has pervaded electronic circuit theory. That misconception is that the fundamental relationship in passive circuitry is between voltage and charge. What the researchers contend is that the fundamental relationship is actually between changes-in-voltage, or flux, and charge. Such is the insight that enabled HP to invent the memristor, according to Chua and Williams.

“Electronic theorists have been using the wrong pair of variables all these years — voltage and charge. The missing part of electronic theory was that the fundamental pair of variables is flux and charge,” said Chua. “The situation is analogous to what is called “Aristotle’s Law of Motion, which was wrong, because he said that force must be proportional to velocity. That misled people for 2000 years until Newton came along and pointed out that Aristotle was using the wrong variables. Newton said that force is proportional to acceleration — the change in velocity. This is exactly the situation with electronic circuit theory today. All electronic text books have been teaching using the wrong variables — voltage and charge–explaining away inaccuracies as anomalies.

Colin Johnson on Chua and the Memristor - InfoWeek, May 2008

From Darkest Troy: Record material from RPI uses nanotubes

RPI researchers demonstrated use of nanotube arrays to dramatically change an object’s optical reflection. As a result, they claim the darkest material to date. They do not just boast – they have actually submitted their claim to the Guiness Book of World Records.

An integrating sphere was used to measure the material’s reflectivity.

Shawn-Yu Lin, professor of physics at Rensselaer and a member of the university’s Future Chips Constellation, and colleagues report on this event in the insert below:

created a coating of low-density, vertically aligned carbon nanotube arrays that are engineered to have an extremely low index of refraction … [to create] a material with a total reflective index of 0.045 percent — more than three times darker than the previous record, which used a film deposition of nickel-phosphorous alloy.

That’s dark matter. It’s also one of many recent signs that recent years’ nano technology efforts may be poised to alter the evolution of many, many fields of endeavor. University information office communication on this breakthrough is available from RPI. Nano news can be found at http://pubs.acs.org/journals/nalefd/index.html

IBM has silicon Mach-Zehnder electro-optic modulator

IBM continues to focus on ways of making multi-cores chips shuttle info between cores. On Dec 6, the company discussed using pulses of light through silicon, instead of electrical signals on wires. A silicon Mach-Zehnder electro-optic modulator does the work of converting electrical signals into pulses of light. The IBM modulator is 100 to 1,000 times smaller in size compared to previously demonstrated modulators of its kind.

Central to the modulator are silicon nanophotonic waveguides that control the flow of light on a silicon chip. The waveguides are made of tiny silicon strips. Strong confinement of light allows the IBM modulator to be dramatically scaled down in size.
 
In April IBM announced success with 3-D chip stacking that eliminated the need for metal wires that connect standard 2-D chips together. The April 3-D demo instead used through-silicon vias etched through a silicon wafer and filled with metal.

On-chip silicon nanophotonics work seems to continue to confirm IBM’s central role in semiconductor advancement. An IMB researcher said nanophotonics can do for computers what fiber optic networks did for the Internet. – Jack Vaughan

http://www-03.ibm.com/press/us/en/pressrelease/22769.wss

Parasites and prophets

Simon And Garfinkle I think said the words of the prophets were written on the tenement halls…they could have added latrine house walls…Following directions found in the Dead Sea Scrolls, archaeologists have discovered the latrines used by the sect that produced the scrolls and found that efforts to achieve ritual purity inadvertently exposed members to intestinal parasites that shortened their lifespan. The young male zealots who established their sect at Qumran chose a life of austerity and isolation, but they could not have foreseen the hardships created by their religiously imposed toilet practices, researchers said last week. “They paid a high price for their holiness,” said archaeologist James D. Tabor of the University of North Carolina at Charlotte, one of the co-authors of a paper appearing in the international journal Revue de Qumran. http://www.chron.com/disp/story.mpl/world/4373955.html At Right: The Dead Sea occurs in a rift zone, where the Arabian tectonic plate (east side) is pulling northward, away from the Africa tectonic plate (west side). Highlands and plateaus on either side of the rift end in escarpments at the seashore. NASA.