Researchers at Washington University in St. Louis collaborated with Tsinghua University researchers to create a new sensor that is capable of detecting and counting tiny individual nanoparticles. The sensor was developed using the Raman scattering process which provides a looser requirement for specific wavelength band for pump lasers.
The Raman microlaser sensor is placed on a dopant-free silicon chip that allows the researchers to use it in different sensing environments by being able to modify the lasing frequency for a specific environment. Eliminating the use of rare-earth ions to “dope” the silicon dioxide chip allowed the researchers to reduce processing steps, reduces costs, and prevents biocompatibility risks. The new sensors could lead to advancements in electronics, biomedical, plasmonics, and metamaterial applications.