Is there anything that lasers can't do? The latest breakthrough comes from a team of researchers at Nanyang Technological University (NTU) who have developed a method for cooling semiconductor material (cadmium sulfide) with lasers. In an article published in Nature, NTU reserachers report on cooling a semiconductor from 20 degrees C (68 degrees F) to -20 degrees C (-4 degrees F) as an initial proof of concept.
Heat is an unwanted side effect of most energy-using devices. In many cases, ranging from portable electronics to medical magnetic resonance imagery equipment to scientific research equipment, the need for keeping the equipment cooled is vital to continued function. At present, equipment such as MRI systems require liquid helium for cooling, but with laser cooling, the system could be made smaller and would not require the extensive cooling hardware that is currently needed.
Cooling gasses with lasers is a known technology, but cooling a solid has not been done previously, although the theory behind it is decades old. "Our initial results published in Nature, have shown that it is possible to laser-cool a semiconductor to liquid nitrogen temperature, so we are aiming to reach an even lower temperature, such as that of liquid helium," said Prof Xiong Qihua, a member of the NTU team.
Other cooling technologies for computers have been proposed which could lead to significant energy savings. But if laser cooling eventually became widely used for other applications, it would make this even more beneficial. Laser cooled equipment could be more energy efficient, and portable electronic equipment with this technology would also potentially prolong battery life.
In addition to the energy benefits, wide-scale development and application of this technology would also drastically reduce the amount of refrigerants needed in industry and technology. Many of the chemicals used in refrigeration equipment are harmful to the Earth's ozone layer or have a significant global warming potential (and many are both). Reducing the need for these chemicals would be an added benefit laser cooling might someday offer.
via: Science Daily
|< Prev||Next >|