Photonic crystals are periodic optical nanostructures that are designed to affect the motion of photons, similar to the way the periodicity of a semiconductor crystal affects the motion of electrons. Photonic crystals are very useful for increasing the efficiency of photovoltaic cells by absorbing light at certain optimal wavelengths thanks to their ability to control and filter light efficiently.
Sergei Belousov and his colleagues at Moscow’s Kintech Lab in collaboration with scientists at the GE Global Research Center in New York state have discovered an application for photonics crystals that can improve light emitting efficiency of tungsten. This may lead to a complete redesign of the light bulb at we know it.
Belousov and his team wanted to find out whether a nanostructure of tungsten can be engineered to create a photonic visible light-emitting infrared light. The team studied the theoretical properties of nanoscopic tungsten log piles and spheres embedded in another medium. They tested their data after creating a tungsten photonic crystal to measure the amount of emitted light occurring at different frequencies. What they discovered is that the structure emits less infrared light while having 15% efficiency – much higher than standard bulk materials.
Why is this important? Belousov and team’s research indicates improvements on the technology are possible. However, more research and testing are needed to determine whether the use of tungsten in light bulbs can achieve widespread use. Compact fluorescent bulbs match the light output of a 100 Watt tungsten bulb using less than 30 Watts, and LED bulbs can by less than 20 Watts. Belousov and his team may have their work cut out, but they believe they have a chance.