Relying on a photonic hook, or a type of near-field, self-bending curved light, an international team of researchers has proposed the creation of a curved laser blade for a medical scalpel. Currently, there are laser scalpels in use that feature axisymmetric focus areas, or a cylindrical blade. According to the researchers introducing the new design, changing the shape of the blade will expand the possibilities of using the laser in medicine, as it is about twice as thin as the cylindrical option.
To bend the beam in their setup, the researchers proposed an amplitude or phase mask at the end of a fiber. The mask redistributes the energy flow within the fiber and forms a curved region of radiation localization at the end of the fiber — representing a photonic hook, said Igor Minin, project manager and professor of electronic engineering at Tomsk Polytechnic University. Simulations showed a curved blade with a length of up to 3 mm, a thickness of approximately 500 μm, and a wavelength of 1550 nm.
“In other words, we add one small element, without affecting the general design and performance of the device, and get changes in the area of the fiber end alone at the tip. The shape and thickness of the blade is changing: It is approximately two times thinner than the axisymmetric option,” Minin said.
Having provided a theoretical basis for the concept, the researchers are preparing to confirm it experimentally at the National Yang-Ming University, in Taiwan.
The research was published in the Journal of Biophotonics (www.doi.org/10.1002/jbio.202000342).