We study the generation of high-harmonic beams by the non-collinear wave mixing of two circularly or elliptically polarized fundamental beams. Changing the ellipticity of the two fundamental beams changes the electric field structure in the focal plane, generating multiple high harmonics beamlets. We show that the ellipticity dependence of the harmonic dipole modulates the near-field harmonic intensity, resulting in the diffraction of the generated harmonics in the far-field.

中文翻译：

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椭圆光栅引起的高次谐波衍射

我们研究了两个圆偏振或椭圆偏振的基本光束的非共线波混合产生的高谐波光束。改变两个基本光束的椭圆率会改变焦平面中的电场结构，从而产生多个高谐波子束。我们表明，谐波偶极子的椭圆度依赖性会调制近场谐波强度，从而导致远场中产生的谐波发生衍射。