By solving a two-dimensional time-dependent Schrödinger equation we investigate high-order harmonic generation (HHG) for the ##IMG## [http://ej.iop.org/images/1612-202X/17/5/055301/lplab7be7ieqn2.gif] {$\mathrm{H}_{2}^{+ }$} molecular ion in a circularly polarized laser pulse (CPLP). A comparison is made between a HHG in a CPLP combined with a terahertz (THz) field and with a static electric field. When the CPLP is combined with a static electric field, it is observed that a double-plateau structure appears, and the harmonic spectrum presents large modulation. With the CPLP with a THz field, a continuum spectrum with a spectral width of about 137 eV from 102 eV to 239 eV can be achieved. The HHG process is studied using the semi-classical three-step model and time-frequency analysis. Our studies show that only one trajectory contributes to HHG when a THz field is added. Furthermore, we present the temporal evolution of the probability density of an electron...

中文翻译：

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H ## IMG ##的高次谐波生成的比较[http://ej.iop.org/images/1612-202X/17/5/055301/toc_lplab7be7ieqn1.gif] {$ _ {2} ^ { +} $}在圆偏振激光脉冲中与太赫兹场和静电场结合

通过求解与时间有关的二维Schrödinger方程，我们研究了## IMG ## [http://ej.iop.org/images/1612-202X/17/5/055301的高次谐波生成（HHG） /lplab7be7ieqn2.gif] {$ \ mathrm {H} _ {2} ^ {+} $}分子离子在圆偏振激光脉冲（CPLP）中。将CPLP中的HHG与太赫兹（THz）场和静态电场进行比较。当CPLP与静电电场结合时，可以观察到出现了双平稳结构，并且谐波频谱呈现出较大的调制度。使用具有THz场的CPLP，可以实现从102 eV到239 eV的光谱宽度约为137 eV的连续谱。使用半经典的三步模型和时频分析研究了HHG过程。我们的研究表明，当添加太赫兹场时，只有一条轨迹有助于HHG。此外，我们给出了电子概率密度的时间演化。