Researchers have developed a new optical system (All-optical methods for igniting chip-based nanolasers) to drive a wide range of highly sensitive nanolasers. This approach could enable chip-based optical communication links to process and transmit data faster than current electronic devices.
“The development of optical communication links with advanced nanolasers will improve the processing of information in data centers and the transmission of information on the Internet,” said the leader of the research team Myung-Ki Kim from Korea University. “It can make high-quality movie broadcasts, make sex and online games bigger, accelerate the expansion of the Internet of Things, and provide the fast connections needed for research. big data.”
In Optica, the Optica Publishing Group’s journal for advanced research, researchers show that integrated nanolaser arrays – in which lasers are only 18 microns – can be efficiently driven and powered by light.
“Optical devices embedded in rings are a promising alternative to embedded electronic devices, which are struggling to meet today’s data handling requirements,” Kim said. “By eliminating the large, complex electrodes that are often used to drive lasers, we have reduced the overall size of the laser system while eliminating the heat generation and scheduling that comes with electrode-based drivers.”
Change of electrodes and light
The new nanolasers can be used in optical integrated circuit systems, which detect, generate, transmit and process information on a microchip through light. Instead of the thin copper wires used in electronic computers, optical circuits use optical waveguides, which allow higher bandwidth and are smaller. However, as the size of optical integrated circuits approaches the nanometer regime, there is a need for new ways to efficiently drive and control their nanometer-sized light sources.
In order to emit light, the laser must be powered by a process called pumping. For nanolaser arrays, this is achieved by using a pair of electrodes for each laser in the array, which requires a lot of space in the chip and energy consumption while causing processing time. To overcome this critical limitation, the researchers replaced these electrodes with a special driver that produces a programmable light pattern through interference. The pump light travels through an optical fiber on which nanolasers are printed.
To demonstrate this approach, the researchers used a high-transfer printing technique to create multiple photonic crystal nanolasers spaced 18 microns apart. These gratings are placed on optical microfiber 2 microns in diameter. This should be done in a way to support nanolaser applications and interference patterns. The interference pattern can be changed by changing the bias and width of the bus line.
Laser control in one line
Experiments showed that the design allowed multiple arrays of nanolasers to be driven using light passing through a single fiber. The results are in good agreement with the numerical calculations and show that the printed nanolaser system is well controlled by the pump-pump interference pattern.
“Laser driving and programming technology can also be applied to chip-based silicon photonic systems, which can play an important role in the development of semiconductor chips or optical and chip connections,” Kim said. . “However, it will be necessary to demonstrate how the spectrum of the silicon waveguide can be controlled independently. If this can be done, it will be a huge improvement in the future of optical communication and ring and optical equipment.
