We demonstrate control of high-harmonic generation (HHG) by a linearly polarized laser field using uniform static magnetic and electric fields parallel to the laser polarization. We show that the harmonic intensity can be considerably increased for particular values of the magnetic field. The maximum values of the harmonic intensity correspond to such values of magnetic induction for which an integer multiple of the classical cyclotron period of the electron’s motion perpendicular to the magnetic field is equal to the return time of the ionized electron wave packet to the nucleus under the influence of the laser field (and static electric field, if present). While a static magnetic field (for the strengths we are considering) only affects the cutoff position slightly, a static electric field can introduce additional plateaus and cutoffs. A properly chosen combination of the static electric and magnetic fields can increase both the harmonic intensity and the harmonic order. For the case of a magnetic field only, the present work expands upon a brief account recently given elsewhere [D. B. Milošević and A. F. Starace, Phys. Rev. Lett. 82, 2653 (1999)]. For both a static B field and for parallel static B and E fields, the present work provides further confirmation of the so called “three-step” model for interpreting quantum-mechanical predictions of HHG.
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机译：我们演示了通过线性极化的激光场使用均匀的静态磁场和平行于激光偏振的电场来控制高谐波产生（HHG）。我们表明，对于特定的磁场值，谐波强度可以大大提高。谐波强度的最大值对应于这样的磁感应强度值，对于该值，垂直于磁场运动的电子的经典回旋加速器周期的整数倍等于电离电子波包返回到磁化场下原子核的时间。激光场（和静电场，如果存在）的影响。虽然静磁场（出于我们正在考虑的强度）仅稍微影响截止位置，但静电场会引入额外的平稳期和截止值。适当选择的静电场和磁场组合可以增加谐波强度和谐波阶数。仅在磁场的情况下，本工作以最近在其他地方给出的简短说明为基础展开[D. B.Milošević和A. F. Starace，物理学。牧师82，2653（1999）]。对于静态B场和并行静态B场和E场，本工作为解释HHG的量子力学预测提供了所谓的“三步”模型的进一步确认。
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