Researchers at Purdue University have developed a new optical material that could enable devices to transmit data up to 10 times faster than conventional technologies and improves upon fiber optics’ ability to modulate how much light is reflected up to 40 percent.
The new material is called plasmonic oxide, an aluminumdoped zinc oxide (AZO). It has drastically lower power consumption compared to conventional optical semiconductors and researchers also see the possibility of developing an optical transistor from the same material, using light instead of electricity to perform the same signal amplification functions as silicon-based transistors.
When conventional semiconductors are exposed to a pulsing laser light, electrons are excited from a lower energy level (valence band) to a higher one (conduction band), thus leaving behind holes in the valence band. They eventually recombine with these holes, and the time it takes for the semiconductor to complete the entire cycle is known as switching time.
Compared to silicon semiconductors, the new AZO material takes just 350 femtoseconds to complete a cycle, which is around 5,000 times faster than conventional crystalline silicon. AZO has been shown to work in the nearinfrared spectrum as well. Optical communications utilize that range of the light spectrum, and AZO’s compatibility with complementary metal-oxide semiconductor (CMOS) manufacturing processes in integrated circuits could allow the production of devices that support ultra-high speed optical communications.