Scientists develop affordable lasers for advanced infrared applications

Lasers of PbS colloidal quantum dots. Credit: ICFO.

Researchers at ICFO have created a cost-effective way to produce lasers that work in the extended short-wave infrared (SWIR) range, a breakthrough that could make advanced laser technologies more accessible for a wide variety of applications.

Their work was recently published in the journal Advanced Materials.

Current SWIR laser technologies are expensive and rely on complicated materials, making them hard to scale for widespread use.

To address these issues, the ICFO team developed a new type of laser using colloidal quantum dots (CQDs) made from lead sulfide (PbS).

These tiny, semiconductor-based particles emit coherent light, a key requirement for lasers, in the extended SWIR range.

What makes this innovation stand out is its simplicity and affordability.

Unlike traditional materials, the PbS quantum dots do not require chemical changes to achieve a wide range of wavelengths, making them versatile and easier to produce.

Additionally, these quantum dots are compatible with silicon CMOS technology, which is used to create integrated circuit chips. This compatibility could lead to their integration into compact, on-chip laser systems.

The researchers also achieved another first: they demonstrated lasing in PbS quantum dots using nanosecond excitation.

This is a significant improvement over previous methods that required bulky and expensive femtosecond laser amplifiers.

By using larger quantum dots, the team increased the dots’ ability to absorb light by ten times, which reduced the energy needed to produce laser light efficiently.

This low-cost, scalable approach could revolutionize industries that rely on SWIR lasers. Potential applications include:

  • Hazardous gas detection: Identifying dangerous gases in industrial or environmental settings.
  • Eye-safe LIDAR systems: Enhancing laser-based distance measuring tools for autonomous vehicles and mapping.
  • Medical imaging: Improving imaging within the SWIR “biological window,” where tissues can be observed in greater detail.
  • Advanced photonics: Enabling better performance in photonic integrated circuits, which are essential for miniaturized optical technologies.

“This is a major shift in infrared laser technology,” said ICREA Professor Gerasimos Konstantatos, who led the study. “For the first time, we’ve achieved lasing in the extended SWIR range with solution-processed materials at room temperature. This opens the door to practical and affordable laser applications.”

This groundbreaking work was carried out by a team of scientists, including Dr. Guy L. Withworth, Dr. Carmelita Roda, Dr. Mariona Dalmases, Dr. Nima Taghipour, Miguel Dosil, Dr. Katerina Nikolaidou, and Hamed Dehghanpour, under the leadership of Prof. Konstantatos.

With this innovation, the team has addressed critical challenges in the field and paved the way for a new era of affordable and scalable laser technologies.

Source: KSR.