A team from the Moscow Institute of Physics and Technology (MIPT) developed a novel compact and powerful ceramic-based laser that will be employed as a minimally traumatic and inexpensive laser scalpel for surgery.
Lasers are used in many areas of our lives, including consumer electronics, medical applications, and meteorology. Laser beams are created when there’s a stimulated emission in an active medium – anything from gas, liquid, crystal or glass. The wavelength of a laser and the efficiency of converting energy into radiation both depend on the parameters of the active medium.
Researcher Ivan Obronov and his colleagues from the Institute of Applied Physics of the RAS and the company IRE-Polus used a ceramic obtained from compounds of rare-earth elements - lutetium oxide with added thulium ions (Tm3+:Lu2O3), to create a laser. It was the thulium ions that enabled the ceramic to generate laser radiation.
"Ceramics are a promising type of medium for lasers because they are produced by sintering powders into a polycrystalline mass," said Obronov. "They are cheaper and easier to manufacture than single crystals, which is extremely important for mass adoption. In addition, it is easy to alter the chemical composition of ceramics, which in turn alters the laser properties."
The laser they developed can convert energy into radiation with an efficiency of more than 50%, while other types of solid state lasers have an average efficiency of approximately 20%. It also generates infrared radiation with a wavelength of about 2 microns. This wavelength is what makes this laser so useful for medical purposes.
"Radiation from the most common infrared lasers, with a wavelength of about 1 micron, has very little absorption and penetrates deep into biological tissue, which causes coagulation and large areas of 'dead' tissue. A surgical scalpel needs to 'operate' at a very specific depth, which is why 2-micron lasers are used, as they do not damage underlying tissue," said Obronov.
According to the scientist, doctors usually use 2-micron flashlamp-pumped holmium lasers, but these devices are very expensive, relatively bulky, and are not very reliable.
Ceramics, on the other hand, are less expensive to manufacture, as well as simpler and more reliable. They are also four times more compact than holmium lasers, which make them ideal for surgical use.
Another potential application of the new ceramic lasers is the composite industry. A ceramic laser could be used to effectively cut and engrave plastics like composite materials.
"Composites are increasingly being used to produce technological equipment such as aircraft," said Obronov. "The wing of the new Russian MS-21 airplane is almost entirely made of composites. A ceramic laser could also be a useful tool for production industries."