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People Spot Mysterious Creature Going Through Dumpsters 

“They called and they were like, ‘She’s completely naked.'”

Graphene shows unusual thermoelectric response to light – MIT News Office.


Graphene shows unusual thermoelectric response to light

Finding could lead to new photodetectors or energy-harvesting devices.

Given the enormous scale of worldwide energy use, there are limited options for achieving significant reductions in greenhouse gas emissions.

October 20, 2011

Photo: Len Rubenstein

Graphene, an exotic form of carbon consisting of sheets a single atom thick, exhibits a novel reaction to light, MIT researchers have found: Sparked by light’s energy, the material can produce electric current in unusual ways. The finding could lead to improvements in photodetectors and night-vision systems, and possibly to a new approach to generating electricity from sunlight.

This current-generating effect had been observed before, but researchers had incorrectly assumed it was due to a photovoltaic effect, says Pablo Jarillo-Herrero, an assistant professor of physics at MIT and senior author of a new paper published in the journal Science. The paper’s lead author is postdoc Nathaniel Gabor; co-authors include four MIT students, MIT physics professor Leonid Levitov and two researchers at the National Institute for Materials Science in Tsukuba, Japan.

Instead, the MIT researchers found that shining light on a sheet of graphene, treated so that it had two regions with different electrical properties, creates a temperature difference that, in turn, generates a current. Graphene heats inconsistently when illuminated by a laser, Jarillo-Herrero and his colleagues found: The material’s electrons, which carry current, are heated by the light, but the lattice of carbon nuclei that forms graphene’s backbone remains cool. It’s this difference in temperature within the material that produces the flow of electricity. This mechanism, dubbed a “hot-carrier” response, “is very unusual,” Jarillo-Herrero says.

Such differential heating has been observed before, but only under very special circumstances: either at ultralow temperatures (measured in thousandths of a degree above absolute zero), or when materials are blasted with intense energy from a high-power laser. This response in graphene, by contrast, occurs across a broad range of temperatures all the way up to room temperature, and with light no more intense than ordinary sunlight.

The reason for this unusual thermal response, Jarillo-Herrero says, is that graphene is, pound for pound, the strongest material known. In most materials, superheated electrons would transfer energy to the lattice around them. In the case of graphene, however, that’s exceedingly hard to do, since the material’s strength means it takes very high energy to vibrate its lattice of carbon nuclei — so very little of the electrons’ heat is transferred to that lattice.

Because this phenomenon is so new, Jarillo-Herrero says it is hard to know what its ultimate applications might be. “Our work is mostly fundamental physics,” he says, but adds that “many people believe that graphene could be used for a whole variety of applications.”

But there are already some suggestions, he says: Graphene “could be a good photodetector” because it produces current in a different way than other materials used to detect light. It also “can detect over a very wide energy range,” Jarillo-Herrero says. For example, it works very well in infrared light, which can be difficult for other detectors to handle. That could make it an important component of devices from night-vision systems to advanced detectors for new astronomical telescopes.

The new work suggests graphene could also find uses in detection of biologically important molecules, such as toxins, disease vectors or food contaminants, many of which give off infrared light when illuminated. And graphene, made of pure and abundant carbon, could be a much cheaper detector material than presently used semiconductors that often include rare, expensive elements.

The research also suggests graphene could be a very effective material for collecting solar energy, Jarillo-Herrero says, because it responds to a broad range of wavelengths; typical photovoltaic materials are limited to specific frequencies, or colors, of light. But more research will be needed, he says, adding, “It is still unclear if it could be used for efficient energy generation. It’s too early to tell.”

“This is the absolute infancy of graphene photodetectors,” Jarillo-Herrero says. “There are many factors that could make it better or faster,” which will now be the subject of further research.

Philip Kim, an associate professor of physics at Columbia University who was not involved in this research, says the work represents “extremely important progress toward optoelectric and energy-harvesting applications” based on graphene. He adds that because of this team’s work, “we now have better understanding of photo-generated hot electrons in graphene, excited by light.”

The research was supported by the Air Force Office of Scientific Research, along with grants from the National Science Foundation and the Packard Foundation.

Iranian security forces quash more protests in Tabriz, Oroumiyeh

Iranian security forces quash more protests in Tabriz, Oroumiyeh
Source: Radio Zamaneh

Iranian security forces descended on demonstrations against the drying of Lake Oroumiyeh in Tabriz and Oroumiyeh in northwestern Iran on Saturday, making numerous arrests.

Lake Urmia (Orumieh) is a salt lake in northwestern Iran near Turkey. The lake is between the provinces of East Azarbaijan and West Azarbaijan, west of the southern portion of the similarly shaped Caspian Sea. It is the largest lake inside Iran, and the third salt water lake on earth, with a surface area of approximately 5,200 km square (2,000 mile square).

News outlets linked to ethnic and human rights activists as well as eyewitness reports indicate that security forces were on alert in various Azerbaijan cities in Iran and confronted the crowds with tear gas and batons.

According to HRANA (the Human Rights Activists News Agency), dozens of people were arrested. Some reports indicate that police used plastic bullets, which led to several injuries among protesters.

The Fars semi-official news agency confirmed the unrest but wrote that the demonstrators were rallied by “ethnic” groups, adding that the demonstrators numbered only about 50 people.

Photos: Lake Orumieh Grappling with Death

The Islamic Republic does not let independent and international media cover social and political protests; therefore, it is not possible to confirm details of the published reports.

Protesters maintain that government policies and mismanagement at the local level are the main causes of the rapid decline in the water levels of Lake Oroumiyeh.

Parliament recently voted down a plan to redirect water from the Aras River to Lake Oroumiyeh, which has led to a new wave of protests by environmental and Azerbaijani activists.

Protests in OrumiehAftermath of protests in the northwestern city of Orumieh (Urmia) on August 27.

Most Unreal Landscapes On Earth

Unreal landscapes on our very much real Earth are like gates to different worlds. These places blow our minds and cross the limits of our imagination.

Here is a collection of ten most alien-looking landscapes on Earth:


Steam, bubbles, rocks and ice combine into breathtaking, though, alien-looking landscape. This is Iceland. The island with no trees, few people and the biggest glacier in Europe called Vatnajökull. Yes! This is Europe, not the moon.

Iceland by stuckincustomsIceland by stuckincustoms

Vatnajökull by eir@si


The hole filled with burning gas called by locals “the door to hell” is in Uzbekistan but could  as well be a quiet spot somewhere on Venus.

Gate to Hell. Credit: englishrussia


Burning gas looks like landscapes of Venus. Credit: englishrussia

Not to be groundless…Venus


The Eye of the Sahara called Richat Structure has a diameter of almost 50 kilometers (30 miles). Placed in Mauritania, it is so huge it can be visible from the space. A meteorite impact? An effect of erosion? A symmetrical uplift? Or maybe three in one? Geologists do not really know how the structure was created.

The Eye

Credit: Viva NOLA

Socotra Island

A long geological isolation and dry, hot and harsh climate made Socotra Island looks like a grotesque computer animation. Hyperbolic plants, funky-looking trees and pink flowers can be great inspiration for graphic designers. The island is situated in the Indian Ocean 250 km from Somalia and 340 km from Yemen and it was isolated from mainland Africa for the last 6 or 7 million years.

Trees on Socotra by soqotra

By soqotra

Socotra beach by Marco Pavan


An ancient, acidic river in Spain – Rio Tinto – is a favourite environment for acid- and metal-loving extremophiles. It does not look like human-friendly and, in fact, it is not, but surely it could quench the Terminator’s thirst.

Rio Tinto by ganso.orgRio Tinto by


The Antelope Canyon, located on Navajo land near Page, Arizona looks more like an oil painting than a rock formation. Not without reasons it is the most visited canyon in the southwest America.

Picturesque rocks by paphio

Yellowstone National Park

The terraces of Mammoth Hot Springs in Yellowstone National Park, in the USA, are created by heat, water, limestone, and rock fracture. The formation is like a living sculpture that is constantly changing by flowing water and erosion. Well…the trees are very much alive as well.

Mammoth Hot Spring by v1ctory 1s m1ne

By v1ctory 1s m1ne

A tree on a walk A tree on a walk. By v1ctory 1s m1ne

Planet Earth

The icy forms of glaciers are located around the world. That’s how I imagine Pluto and Neptune, the coldest planets in the solar system.

Hubbard Glacier is the longest tidewater glacier in Alaska by bob…

Grey Glacier, Chile by tom holub

Le Perito Moreno Glacier, Argentina by ricardo.martins


The Mars’ landscapes of Skagen in Denmark do not really fit into the image of the richest and most developed country in the world. The moving dunes and deserted beaches run into the end of Europe where the Baltic Sea clashes with the North Sea.

Somewhere in Skagen

Where Baltic meets North Sea by goandgo

Skagen or Mars? by cmdrcord

Mars or Skagen? Credit: apod


Salar de Uyuni, the world’s largest salt flat, is located in southwest Bolivia. The salt desert surrounded by cactuses, volcanoes and geysers looks as if it was a remote planet, far from our solar system.

So the salt does not come from the supermarket. By calimero74

Yellow plants around Salar de Uyuni by Calvin-C

By Calvin-C