Scientists at ITMO University have developed a way to control light ultra-fast using laser pulses. According to the university, the new technology works thousands of times faster than existing solutions and does not require mechanical or electrical intervention.
The main advantage of our approach is speed and energy efficiency. If you control light through heating, the process takes microseconds, and we have achieved switching faster by hundreds of thousands of times. At the same time, due to the fact that the semiconductor layer is only three atoms thick, switching requires much less laser power than in other optical methods. And working at room temperature allows us to integrate our solution into real computing devices on a chip.
As devices shrink in size, traditional conductors are less able to cope with the load, especially when processing artificial intelligence tasks. Photonic chips, where information is transmitted by light particles, are becoming an alternative, but they are much more difficult to control.
The new approach is based on working with exciton-polaritons, hybrid particles that combine the properties of light and matter. If earlier scientists controlled them mechanically by changing the distance between elements, now they use ultrashort laser pulses. They change the properties of particles and allow you to "switch" light in less than one trillionth of a second.
To implement the method, the researchers integrated an atomically thin layer of semiconductor into a special waveguide and used an improved optical observation system. This made it possible to control the process without interfering with the structure of the device.
According to the developers, the technology could form the basis of optical modulators and logic elements for photonic microcircuits. In the next 2–3 years, the team plans to create a prototype chip that can control light at specified points. In the future, such solutions can be used in supercomputers and telecommunications equipment.
