Thermal modulator advances PICs
Researchers have developed a compact thermal polarisation modulator that uses a phase-change material to control light without moving parts, offering a new route to higher-capacity optical communications and photonic computing.
Researchers at the Skolkovo Institute of Science and Technology (Skoltech) have developed a prototype thermal polarisation modulator that controls light using a phase-change material rather than mechanical motion, paving the way for faster and more compact optical communication systems.
Led by Nicolas Posunko, the team created the device using germanium-antimony-tellurium (GST), a phase-change material that reversibly switches between crystalline and amorphous states. Integrated into a microscopic diffraction grating, the GST layer changes the polarisation of transmitted light when heated, enabling optical switching without rotating components.
The compact modulator, measuring less than one-hundredth of a square centimetre, demonstrates a non-mechanical approach to polarisation control that could improve the speed, reliability and scalability of integrated photonic systems.
The proof-of-concept prototype used furnace annealing and laser scanning to maximise optical contrast, with future versions expected to employ faster electrical heating for practical applications.
By using polarisation as an additional data channel, the technology could increase the capacity of optical transceivers without requiring extra fibres or wavelengths.
The researchers say the approach could support next-generation fibre-optic communications, AI data centres, high-performance computing and emerging photonic computing platforms.
Beyond communications, the non-mechanical design could also benefit integrated photonic circuits and optical signal processing, where compact, programmable optical components are increasingly important for scaling future photonic systems.
