文档介绍：Solar Power without Solar Cells
A dramatic and surprising ic effect of light discovered by University of Michigan1 researchers could lead to solar power without traditional semiconductor-based solar cells.
The researchers found a way to make an "optical
battery," said Stephen Rand, a professor in the departments of Electrical Engineering puter Science, Physics and Applied Physics.
Light has electric and ponents. Until now, scientists thought the
effects of the ic field were so weak that they could be ignored. What Rand and his colleagues found is that at the right intensity, when light is traveling through a material that does not conduct electricity, the light field can generate ic effects that are 100 million times stronger than
previously expected. Under these circumstances, the ic effects develop strength equivalent to a strong electric effect.
"This could lead to a new kind of solar cell without semiconductors and without absorption to produce charge separation,"
Rand said. "In solar cells, the light goes into a material, gets absorbed and creates heat. Here, we expect to have a very low heat load2. Instead of the light being absorbed, energy is stored in the ic moment
3. Intense ization can be induced by intense light and then it is ultimately capable of providing a capacitive power source."What makes this possible is a previously undetected brand of "optical rectification
4," says William Fisher, a doctoral student5 in applied physics. In traditional optical rectification, light's electric field causes a charge separation, or a pulling apart of the positive and negative charges6 in a material. This sets up a voltage, similar to
that in a battery.
Rand and Fisher found that under the right circumstances and in right types of materials, the light's ic field can also create optical rectification. The light must be shone through7 a material that does not conduct electricity, such as glass. And it must be focused to an intensity of 10 million wat