Air wedge with variable refractive index for precise laser beam steering in a small range

Abstract

This paper provides the results of work on a new method for metrological laser beam steering for the purpose of angular stabilization. Frequency stabilized metrological lasers are used for interference measurements of length and angle. Angular deviation of the beam may cause cosine errors when measuring displacements. This paper presents a method for metrological laser beam deflection with an air wedge of variable refractive index. The change in the index is achieved by changing the air pressure in the wedge volume. The implemented system produced a range of angular displacements of the 0.1 mrad (10 rad; 100 μrad) beam with a resolution of 10 rad.

Exploring the quantum vacuum via ultraintense laser-induced refraction of light

“…This small deflection is enough to realize interferometric measurement by changing the interference fringe. The state-of-art interferometry, which proposed for the ultra precise measurement of the small laser angular deflection, can provide the resolution on the single nrad-level and extremely robust and insensitive to the most common disturbances [42,43].…”

“…Meanwhile, one may anticipate that the vacuum refraction is also one of the basic and critical effects of this vacuum medium [41]. Additionally, it provides an alternative method for detecting quantum vacuums as the precision of beam angle measurements advances to the nano-radian scale and further [42,43]. Some early attempts to study vacuum refraction signals can be found in [44,45].…”