The United States to stimulate the study of micro crystal luminescence technology

American scientists have developed a new method to stimulate micro nano crystal light, this method can be used in the manufacture of higher brightness, lower energy consumption and longer life of the display equipment, traffic lights and indoor lighting etc.. Using light emitting diode life of semiconductor manufacturing is very long, only 1/5 of the energy consumption of ordinary light bulbs, has been used in traffic lights and other equipment. But they tend to emit blue light, and white light must be converted, which reduces efficiency. To solve this problem, the semiconductor material is made into tiny nanocrystals, which are called "quantum dots", which can change the color of the light they emit. But nano crystal surface to be coated with a layer of organic molecules, which will hinder the foreign electronic stimulation of quantum dot luminescence. Scientists at the National Laboratory in Los Alamos, the United States will be placed in a quantum dot CdSe quantum dots called quantum wells on the device, the use of quantum wells as the media indirectly stimulate the quantum dot luminescence. Rough calculation shows that the new method can make the efficiency of light-emitting diodes is twice as high as the current products. The results were published in the 10 issue of the British Journal nature. Quantum wells has a sandwich like structure, the middle layer of the semiconductor film is very thin, the lateral isolation layer is two. Using a laser to flash toward a quantum well, electrons and positively charged holes are created in the intermediate semiconductor layer. In general, electrons combine with holes and emit photons. Scientists have made the upper layer of the quantum well so thin that it is less than 30 thick, which forces the electrons and holes in the intermediate layer to combine to release energy in the form of a varying electric field rather than a photon. The role of the electric field in the vicinity of the quantum dot to generate new electrons and holes, so that they combine and emit photons. To the practical development of lighting equipment, the next step will try to use electronic instead of laser to excite quantum wells. Experts believe that this is only an engineering problem.