How much light can only be produced by a light bulb?

CnBeta Reuters, 130 years ago, Thomas Edison made the world's first commercial carbon filament lamp bulb.

Now, from the Columbia University, Seoul National University (SNU), the research team and the Korean standard Science Research Institute, has been in the form of perfect crystallization of the same elements - carbon (Shi Moxi) - made the world's thinnest light bulb.

Although its filament is only a layer of atoms thick, but it can still be easily visible to the naked eye.

Professor Young Duck Kim and James Hone.

The graphene micro filament attached to the metal electrode, and then hung on the silicon substrate, and the current through the filament is heated to above 2500 degrees Celsius (4500 degrees Fahrenheit), which issued a very bright light.

The researchers used graphene to create the world's thinnest on-chip light source.

Hone, Professor of mechanical engineering at Columbia University James:

"We have created the world's thinnest bulb, the new 'broadband' light source can be integrated into the chip, and to achieve thin flexible transparent display, and pave the way for atom chip communication based on graphene".

Interestingly, although the temperature of graphene is so high, it does not melt the substrate or metal electrode. This is because, when graphene is heated, its heat is not able to pass from itself.

The result is that the heat is concentrated and confined in the middle of the filament, which gives off a strong light. The spectral measurements show that the peak value has exceeded people's expectations, which is caused by the interference of the light emitting filament and the silicon substrate.

Unlike any common filament, because the material is transparent, this phenomenon can only occur on graphene. By changing the distance between the substrate and the substrate, the researchers were able to adjust the emission spectrum.

Graphene lattice (graphene lattice) can also be highly efficient luminescence, because of its intrinsic strength can maintain the level of excitation, and allow the free flow of electrons.

That is to say, just as graphene can emit electrons in a rising state (elevated state), it can also effectively release photons in the case of electric heating.

KRISS senior researcher Myung-Ho Bae said:

At the highest temperature, the electron temperature is much higher than that of the graphene lattice. This unique thermal properties allow us to heat the suspended graphene to half the temperature of the sun and increase the efficiency of the solid substrate by 1000 times.

At present, researchers are trying to improve these photothermal devices so that they can quickly turn on / off (produce 0 and 1 signals) and applied to optical communications. Of course, they will explore ways to incorporate them into flexible materials.

The results of this study were published in the recent issue of the journal Nature Nanotechnology (Nanotechnology) (Nature).

For more information about LED, please click on China LED network or pay attention to WeChat public account (cnledw2013).