Lifeboat Foundation

“Over decades, both military and space programs all around the world have known the negative impact of radiation on semiconductor-based electronics,” says Meyya Meyyappan, Chief Scientist for Exploration Technology at the Center for Nanotechnology, at NASA’s Ames Research Center. What has changed with the push towards nanoscale feature sizes is that terrestrial levels of radiation can now also cause problems that had previously primarily concerned applications in space and defence. Packaging contaminants can cause alpha radiation that create rogue electron-hole pairs, and even the ambient terrestrial neutron flux at sea level – around 20 cm⁻² h⁻¹ – can have adverse implications for nanoscale devices.

Fortunately work to produce radiation-hardy electronics has been underway for some time at NASA, where space mission electronics are particularly prone to radiation exposure and cumbersome radiation shielding comes with a particularly costly load penalty. Vacuum electronics systems, the precursors to today’s silicon world, are actually immune to radiation damage. Alongside Jin-Woo Han and colleagues Myeong-Lok Seol, Dong-Il Moon and Gary Hunter at Ames and NASA’s Glenn Research Centre, Meyyappan has been working towards a renaissance of the old technology with a nano makeover.

In a recent Nature Electronics article, they report how with device structure innovations and a new material platform they can demonstrate nanoscale vacuum channel transistors that compete with solid-state system responses while proving impervious to radiation exposure.

Circa 2009

In just over a day, a powerful computer program accomplished a feat that took physicists centuries to complete: extrapolating the laws of motion from a pendulum’s swings.

Developed by Cornell researchers, the program deduced the natural laws without a shred of knowledge about physics or geometry.

Continue reading “Computer Program Self-Discovers Laws of Physics” »

Truthfully, it has been some time since Moore’s law, the propensity for processors to double in transistor count every two years, has been entirely accurate. The fundamental properties of silicon are beginning to limit development and will significantly curtail future performance gains, yet with 50 years and billions invested, it seems preposterous that any ‘beyond-silicon’ technology could power the computers of tomorrow. And yet, Nano might do just that, by harnessing its ability to be designed and built like a regular silicon wafer, while using carbon to net theoretical triple performance at one-third the power.

Nano began life much like all processors, a 150mm wafer with a pattern carved out of it by a regular chip fab. Dipped into a solution of carbon nanotubes bound together like microscopic spaghetti, it re-emerged with its semi-conductive carbon nanotubes stuck in the pattern of transistors and logic gates already etched on it. It then undergoes a process called ‘RINSE,’ removal of incubated nanotubes through selective exfoliation, by being coated with a polymer then dipped in a solvent. This has the effect of reducing the CNT layer to being just one tube, removing the large clumps of CNTs that stick together over 250 times more effectively than previous methods.

One of the challenges facing CNT processors has been difficulty in separating N-type and P-type transistors, which are “on” for 1 bit and “off” for 0 bit and the reverse, respectively. The difference is important for binary computing, and to perfect it, the researchers introduced ‘MIXED,’ metal interface engineering crossed with electrostatic doping. Occurring after RINSE, small platinum or titanium components are added to each transistor, then the wafer is coated in an oxide which acts as a sealant, improving performance. After that, Nano was just about done.

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This week a collaborative effort among computer scientists and academics to safeguard data is winning attention and it has quantum computing written all over it.

The Netherlands’ Centrum Wiskunde & Informatica (CWI), national research institute for mathematics and computer science, had the story: IBM Research developed “quantum-safe algorithms” for securing data. They have done so by working with international partners including CWI and Radboud University in the Netherlands.

IBM and partners share concerns that data protected by current encryption methods may become insecure within the next 10 to 30 years.

A team of researchers at the University of Virginia has recently carried out a large-scale analysis aimed at identifying features in film trailers that best predict a movie’s genre and estimated budget. In their study, outlined in a paper pre-published on arXiv, the researchers specifically compared the effectiveness of visual, audio, text, and metadata-based features.

“Video understanding is the next frontier after image understanding,” Vicente Ordonez, one of the researchers who carried out the study, told TechXplore. “However, much work on video understanding has so far focused on short clips with a human performing a single action. We wanted something longer, but there is also the issue of computational power. Video trailers seemed like an intermediate compromise, as they display a multitude of things, from scary to funny.”

Movie trailers are short and can easily be paired with movie descriptions. Ordonez and his colleagues realized that these characteristics make them ideal to investigate parallels between video and language.

If you’ve ever been wakened by the roar of a freight train – or waited at a level crossing for one to trundle by – you’ll be glad to know that these noisy vehicles have a new and potentially life-saving purpose: predicting earthquakes. As Hamish Johnston explains on this week’s podcast, freight trains generate surprisingly strong seismic waves, and changes in the velocity of these waves is an early sign of hazardous earthquake activity. Researchers in France, Belgium and the US studied the rumblings of freight trains running through California’s Coachella Valley and found that they could, in principle, be used to monitor the nearby San Jacinto fault.

Next on the podcast is Chris Monroe, an atomic physicist and quantum technologist whose start-up firm, Ion Q, is developing a quantum computer that uses trapped ions as qubits. In an interview with Physics World’s industry editor Margaret Harris, Monroe explains how Ion Q’s technology differs from classical computers, and describes how trapped ions execute quantum gates.

The third segment of the podcast focuses on the persistent lack of diversity in physics. In an interview, Jess Wade, a physicist at Imperial College London, discusses the scientific impact of this poor diversity and suggests ways to make the field more welcoming to members of underrepresented groups. Afterwards, our features editor Sarah Tesh, who commissioned Wade and Maryam Zarainghalam to write about this topic in the August issue of Physics World, talks about the portraits of white male scientists that adorn walls in many physics departments. These so-called “dude walls” honour important historical figures, but they also send out subtle signals about what a “great” physicist looks like.

MIT researchers have found new ways to cure headaches in manufacturing carbon nanotube processors, which are faster and less power hungry than silicon chips.

Light and sound waves are at the basis of energy and signal transport and fundamental to some of our most basic technologies—from cell phones to engines. Scientists, however, have yet to devise a method that allows them to store a wave intact for an indefinite period of time and then direct it toward a desired location on demand. Such a development would greatly facilitate the ability to manipulate waves for a variety of desired uses, including energy harvesting, quantum computing, structural-integrity monitoring, information storage, and more.

In a newly published paper in Science Advances, a group of researchers led by Andrea Alù, founding director of the Photonics Initiative at the Advanced Science Research Center (ASRC) at The Graduate Center, CUNY, and by Massimo Ruzzene, professor of Aeronautics Engineering at Georgia Tech, have experimentally shown that it is possible to efficiently capture and store a wave intact then guide it towards a specific location.

“Our experiment proves that unconventional forms of excitation open new opportunities to gain control over wave propagation and scattering,” said Alù. “By carefully tailoring the time dependence of the excitation, it is possible to trick the wave to be efficiently stored in a cavity, and then release it on demand towards the desired direction.”