Researchers have introduced a groundbreaking laser technology utilizing large colloidal quantum dots made of lead sulfide to emit coherent light in the extended short-wave infrared (SWIR) range. This advancement offers a solution for creating affordable, scalable laser systems that are compatible with silicon CMOS platforms. The technology covers a broader wavelength range without altering the chemical composition and eliminates the need for expensive femtosecond laser amplifiers.
Innovative Laser Technologies
Traditional lasers operating in the extended SWIR range are based on expensive and complex materials, limiting their scalability and affordability. To address these challenges, a team from ICFO, led by ICREA Professor Gerasimos Konstantatos, developed a novel approach using colloidal quantum dots (CQDs). Their research, published on December 6 in Advanced Materials, demonstrates that large lead sulfide (PbS) CQDs can emit coherent light, which is essential for creating lasers in the extended SWIR range.
This breakthrough not only solves issues related to cost and scalability but also ensures compatibility with silicon CMOS platforms, the standard technology used in integrated circuit chip fabrication. This compatibility enables easier integration into existing systems, making it a more accessible and practical solution for laser applications.
Progress in Quantum Dot Lasers
The PbS colloidal quantum dots represent the first semiconductor lasing material that covers such a wide wavelength range. Remarkably, the researchers achieved this without changing the chemical makeup of the dots. This achievement marks a significant step toward the development of smaller, more practical quantum dot lasers.
Additionally, the team demonstrated lasing with nanosecond excitation in PbS quantum dots for the first time, eliminating the need for bulky and expensive femtosecond laser amplifiers. By using larger quantum dots, the absorption cross-section of the dots increased tenfold, leading to a drastic reduction in the optical gain threshold—enabling efficient laser light emission.
Potential Applications and Impact
The development of low-cost, scalable infrared lasers in the extended SWIR range could address key challenges in various industries. This innovation has the potential to revolutionize applications such as hazardous gas detection, eye-safe LIDAR systems, advanced photonic integrated circuits, and SWIR biological imaging.
Industries that rely on LIDAR systems, gas sensing, and biomedicine stand to benefit from this affordable and integrable solution. Furthermore, the breakthrough supports the evolution of silicon-compatible photonic integrated circuits, allowing for greater miniaturization and widespread adoption.
A Paradigm Shift in Laser Technology
ICREA Professor Gerasimos Konstantatos noted, “Our work represents a paradigm shift in infrared laser technology. For the first time, we’ve achieved lasing in the extended SWIR range with solution-processed materials at room temperature, paving the way for practical applications and the development of more accessible technologies.”
