The Imbert–Fedorov (IF) shift, which refers to a tiny transverse
splitting induced by spin–orbit interaction at a reflection/refraction
interface, is sensitive to the refractive index of a medium and
momentum state of incident light. Most studies have focused on the
shift for an incident light beam with a spin angular momentum (SAM),
i.e., circular polarization. We demonstrate experimentally that
the relative IF shifts of vortex beams with large opposite orbital
angular momentums (OAMs) are highly enhanced in resonant structures
when light refracts through a double-prism structure (DPS), in which
the thickness and temperature of the air gap are precisely sensed via
the observed relative IF shifts. The thickness and temperature
sensitivities increase as the absolute value of opposite OAMs
increases. Our results offer a technological and practical platform
for applications in sensing of thickness and temperature, ingredients
of environment gas, spatial displacement, chemical substances and
deformation structure.