Improved nonparaxial accelerating beams due to additional off-axis spiral phases.
An accelerating beam with a Gaussian transverse profile can preserve its shape while propagating along a quarter of a circle. When an off-axis spiral phase is imposed, however, the beam will have an additional acceleration perpendicular to the circle. A two-dimensional accelerating beam is constructed and is found to accelerate along both the x and the y directions, but its transverse intensity profile cannot be maintained well due to the interaction of accelerations along different directions. The intensity profile can be improved by imposing two off-axis spiral phases onto the input beam.
Wenguo
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Zhu
Weilong
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