Cryogenic Lasers Offer High-Speed Data for Sensitive Sensors
Researchers have developed cryogenic vertical-cavity surface-emitting lasers (cryo-VCSELs) that can transmit data at speeds up to 138 Gb/s per lane with minimal heat generation, potentially revolutionizing sensor technology.
Focal plane arrays (FPAs), crucial for applications like surveillance and astronomy, convert infrared light into electrical signals for thermal imaging. While advancements have increased their resolution and sensitivity, they now demand data rates exceeding 100 gigabits per second. Traditional electrical connections struggle with these demands, introducing heat that can degrade FPA performance and increase cooling needs.
To address this, a study published in IEEE Photonics Technology Letters explored the use of cryo-VCSELs for high-bandwidth optical interconnects within FPAs. These devices offer a compact form factor, high bandwidth, and low energy consumption at cryogenic temperatures, while significantly reducing heat transfer compared to electrical methods.
The researchers engineered a cryo-VCSEL with a 4.5-micrometer oxide aperture and a half-wavelength cavity. Experiments conducted between 77 K and 120 K demonstrated a consistent relationship between input current and light output, with maximum optical power reaching 13.35 milliwatts at 77 K. The device also exhibited robust high-frequency performance, achieving a modulation bandwidth exceeding 50 gigahertz.
Crucially, the cryo-VCSELs successfully transmitted data at rates up to 138 Gb/s per lane using PAM-4 modulation, meeting industry standards for short-reach communication. The system maintained low signal distortion and operated with an energy efficiency of approximately 60–68 femtojoules per bit. This development suggests cryo-VCSEL optical links could provide a cost-effective solution for high-speed data communication in FPAs and potentially enable interfaces for cryogenic computing.
This development is significant for additive manufacturing by enabling higher-performance, lower-power electronic systems operating at cryogenic temperatures. Such advancements are critical for sophisticated sensors used in extreme environments, including space exploration and potentially in-situ manufacturing on other celestial bodies where thermal management is paramount.
Edited by the news editor with AI from the original report — please refer to the original source.