UW-Madison engineers reveal record-setting flexible phototransistor

MADISON, Wis. -- Inspired by mammals' eyes, University of Wisconsin-Madison electrical engineers have created the fastest, most responsive flexible silicon phototransistor ever made.

The innovative phototransistor could improve the performance of myriad products -- ranging from digital cameras, night-vision goggles and smoke detectors to surveillance systems and satellites -- that rely on electronic light sensors. Integrated into a digital camera lens, for example, it could reduce bulkiness and boost both the acquisition speed and quality of video or still photos.

Developed by UW-Madison collaborators Zhenqiang "Jack" Ma, professor of electrical and computer engineering, and research scientist Jung-Hun Seo, the high-performance phototransistor far and away exceeds all previous flexible phototransistor parameters, including sensitivity and response time.

The researchers published details of their advance this week in the journal Advanced Optical Materials.

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UW-Madison: Dark energy to be topic of Space Place event

"To Infinity and Beyond: The Accelerating Universe," a live broadcast from the World Science Festival about dark energy, an antigravitational force that confounds the conventional laws of physics, will be hosted on the evening of May 28 by UW-Madison'sSpace Place.

Originating from New York and moderated by internationally known theoretical physicist and bestselling author Lawrence Krauss, the broadcast will take place from 7 to 8:30 p.m. Thursday. Space Place, the UW-Madison astronomy outreach outpost, is located in the Villager Mall, 2300 S. Park St. The event will be held in the mall atrium.

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UW-Milwaukee researchers to lead search for gravitational waves

By Mark Johnson

Researchers at the University of Wisconsin-Milwaukee will lead a new effort to detect low-frequency gravitational waves, a discovery that would give mankind a new picture of the universe and confirm one of the last unresolved predictions of Albert Einstein's theory of general relativity.

The project, which includes more than 60 scientists and students at 11 institutions, has just received a five-year, $14.5 million grant from the National Science Foundation.

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Dark matter: Out with the WIMPs, in with the SIMPs?

By Adrian Cho

Like cops tracking the wrong person, physicists seeking to identify dark matter—the mysterious stuff whose gravity appears to bind the galaxies—may have been stalking the wrong particle. In fact, a particle with some properties opposite to those of physicists' current favorite dark matter candidate—the weakly interacting massive particle, or WIMP—would do just as good a job at explaining the stuff, a quartet of theorists says. Hypothetical strongly interacting massive particles—or SIMPs—would also better account for some astrophysical observations, they argue.

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A new way to make laser-like beams using 1,000x less power

ANN ARBOR—With precarious particles called polaritons that straddle the worlds of light and matter, University of Michigan researchers have demonstrated a new, practical and potentially more efficient way to make a coherent laser-like beam.

They have made what's believed to be the first polariton laser that is fueled by electrical current as opposed to light, and also works at room temperature, rather than way below zero.

Those attributes make the device the most real-world ready of the handful of polariton lasers ever developed. It represents a milestone like none the field has seen since the invention of the most common type of laser – the semiconductor diode – in the early 1960s, the researchers say. While the first lasers were made in the 1950s, it wasn't until the semiconductor version, fueled by electricity rather than light, that the technology took off.

This work could advance efforts to put lasers on computer circuits to replace wire connections, leading to smaller and more powerful electronics. It may also have applications in medical devices and treatments and more.

The researchers didn't develop it with a specific use in mind. They point out that when conventional lasers were introduced, no one envisioned how ubiquitous they would become. Today they're used in the fiber-optic communication that makes the Internet and cable television possible. They are also in DVD players, eye surgery tools, robotics sensors and defense technologies, for example.

A polariton is part light and part matter. Polariton lasers harness these particles to emit light. They are predicted to be more energy efficient than traditional lasers. The new prototype requires 1,000 times less electricity to operate than its conventional counterpart made of the same material.

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UWM physicists win prestigious National Science Foundation grant

By Mark Johnson of the Journal Sentinel

Physicists at the University of Wisconsin-Milwaukee, who have been developing three dimensional images of the structure and movement of proteins, won a prestigious National Science Foundation grant Wednesday.

The team, whose work could help drug companies design new medications, will share in a $25 million grant with colleagues at seven other institutions. UWM's share will come to a little less than $4 million over 5 years.

Proteins are crucial to virtually every human action from breathing to thinking and many diseases result from problems with how they are made or how they function.

Six hundred applications were received for grants to establish National Science and Technology Centers. Just three were accepted. In addition to the award made to UWM and its partners grants were given to groups led by Harvard University and the Massachusetts Institute of Technology.

"It's like the Olympic Games where there are three medals," said Abbas Ourmazd, a member of the team that won the grant and a distinguished professor of physics and electrical engineering. "It's an objective metric for the league UWM is playing in."

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Nuclear fusion milestone passed at US lab

By Paul Rincon

Science Editor, BBC News website

Researchers at a US lab have passed a crucial milestone on the way to their ultimate goal of achieving self-sustaining nuclear fusion.

Harnessing fusion - the process that powers the Sun - could provide an unlimited and cheap source of energy.

But to be viable, fusion power plants would have to produce more energy than they consume, which has proven elusive.

Now, a breakthrough by scientists at the National Ignition Facility (NIF) could boost hopes of scaling up fusion.

NIF, based at Livermore in California, uses 192 beams from the world's most powerful laser to heat and compress a small pellet of hydrogen fuel to the point where nuclear fusion reactions take place.

The BBC understands that during an experiment in late September, the amount of energy released through the fusion reaction exceeded the amount of energy being absorbed by the fuel - the first time this had been achieved at any fusion facility in the world.

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Bad Cable May Be to Blame in Flawed Faster-Than-Light Experiment

By GAUTAM NAIK

A malfunctioning cable may have been responsible for the claim that some particles may be able to travel faster than light speed, a potentially embarrassing outcome for physicists who had publicized the findings with great fanfare just a few month ago.

In September, scientists at the European Organization for Nuclear Research, or CERN, said that ghostlike particles called neutrinos zapped from a lab in Geneva to one in Italy had seemingly made the trip in about 60 nanoseconds less than light speed—a finding that garnered headlines around the world. It also induced much head-shaking among skeptical scientists who said they were convinced that the result was an error.

It turns out the only ghost may have been in the machine after all. CERN says it had identified two possible effects that could have affected the experiment: one relates to an oscillator used to provide time stamps for estimating particle speeds, and a possible glitch in a fiber-optic cable.

"If this is the case, it could have led to an underestimate of the time of flight of the neutrinos," CERN said in a one-paragraph "update" posted on its website. It plans new measurements in May.

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UW superheating project aims to explore magnetic fields

Big aluminum sphere will heat gases to 500,000 degrees

By Karen Herzog of the Journal Sentinel

Researchers will be able to simulate the superheated gases that form the sun's magnetic field with a one-of-a-kind sphere that moved Wednesday into a new physics lab at the University of Wisconsin-Madison.

The hollow aluminum sphere, built by four Wisconsin companies for $2.5 million, looks like the famous Death Star from "Star Wars" movies. Weighing 11,000 pounds, it was built to superheat gases to 500,000 degrees Fahrenheit.

Researchers say it will help them study how magnetic fields are generated in planets and stars, and better understand why the sun occasionally spews out particles that affect the Earth as "space weather," knocking out satellites and even taking down power grids, explained Cary Forest, a UW-Madison physics professor.

Forest is principal investigator for the effort, known as the Madison Plasma Dynamo Experiment.

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Rumors Explode Over Higgs Boson Discovery

By Ian O'Neill

Published December 07, 2011 | Discovery News

This could be the announcement we've all been waiting for. As soon as the Large Hadron Collider (LHC) revved up its supercooled electromagnets in 2008 -- which promptly "quenched" (read: broke down in a very expensive way) and then restarted the following year -- it's been the one piece of news the world has been eagerly awaiting: confirmation of the discovery of one of the Universe's most secretive particles -- the Higgs boson.

After gazillions of particle collisions and countless rumors of Higgs discoveries, we have... yet another rumor of a Higgs discovery.

But this time, the rumor seems to be meatier than ever.

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