Fluidic laser beam shaper based on thermal lens effect in MoS₂ and its application in optical trapping

Abstract

In this work, we develop a fluidic laser beam shaper based on the thermal lens effect in MoS₂ suspensions. It is demonstrated that another weak unfocused Gaussian beam (probe beam) is transformed into an annular beam due to the thermal lens effect resulting from a strong focused Gaussian beam (pump beam). The time evolution of the generated annular beam is studied, and the result shows that the annular beam exhibits asymmetric caused by heat convection with the high pump beam power. In addition, the tunability of the generated annular beam is investigated. Furthermore, the optical trapping of micro-sized particles in air using the annular beam is researched. It is found that this method exhibits stable performance capture for 3 h. The advantages of adjustable size, flexible setup and low cost of annular beam generated method are significant for lots of laser applications, such as optical trapping, optical imaging and laser machining.

KEYWORDS:

• Laser beam shaper
• thermal lens effect
• annular beam

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by the National Natural Science Foundation of China [Grant Nos. 12104365; 12104368; 12904329], Education Department of Shaanxi Province [Grant Nos. 21JK0915; 21JK0917; 23JK0667].