论文标题
在强场电离中的无脱唑效应
Electric Nondipole Effect in Strong-Field Ionization
论文作者
论文摘要
通过圆极化飞秒激光脉冲对原子的强场电离产生甜甜圈形的电子动量分布。在偶极子近似中，相对于极化平面，该分布是对称的。已知光场的磁成分向前移动。在这里，我们表明这种磁非偶极效应并不是强场电离中唯一的非偶极效应。我们发现，由于电场的位置依赖性，可以类似于多普勒效应，因此会产生电非偶极效应。该电非二极管效应表现为对向前定向动量的甜甜圈光电子动量分布的半径增加，并减少了反向定向电子的半径。我们提供了实验数据，显示了电非偶极效应的这种指纹，并将我们的发现与经典模型和量子计算进行了比较。
Strong-field ionization of atoms by circularly polarized femtosecond laser pulses produces a donut-shaped electron momentum distribution. Within the dipole approximation this distribution is symmetric with respect to the polarization plane. The magnetic component of the light field is known to shift this distribution forward. Here, we show that this magnetic non-dipole effect is not the only non-dipole effect in strong-field ionization. We find that an electric non-dipole effect arises that is due to the position dependence of the electric field and which can be understood in analogy to the Doppler effect. This electric non-dipole effect manifests as an increase of the radius of the donut-shaped photoelectron momentum distribution for forward-directed momenta and as a decrease of this radius for backwards-directed electrons. We present experimental data showing this fingerprint of the electric non-dipole effect and compare our findings with a classical model and quantum calculations.
