| 论文标题 |
Dramatic enhancement of high-order-harmonic generation via the quantum interference of dipole-transition paths |
| 作者 |
Zhao, D (Zhao, Di)[ 1 ] ; Jiang, CW (Jiang, Chen-Wei)[ 1 ] ; Li, FL (Li, Fu-li)[ |
| 发表/完成日期 |
2015-03-27 |
| 期刊名称 |
PHYSICAL REVIEW A |
| 期卷 |
91 |
| 相关文章 |
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| 论文简介 |
We present a theoretical study of the high-order-harmonic generation (HHG) from coherent superposition states of a three-level system driven by monochromatic cw laser fields. The HHG spectrum can be enhanced by about 105 times via tuning the relative phase between the stateswhich are initially prepared. Even if the ionization effects are taken into account, the enhancement factors are still up to about 102 times. The enhancement is interpreted as the quantum constructive interference of different dipole transitions between quasienergy states. To realize the interference, the intensity of the driving laser field is chosen such that frequencies of the harmonics generated from the different dipole-transition paths, which are dependent on the ac Stark shifted energy separation of quasienergy states, are equal to each other. Moreover, the case studies of HHG spectra from a coherent superposition state of a three-level system show that the enhancement of harmonics is closely related to the harmonic strengths of the dipole transitions, as well as the parity of quasienergy states which are involved in the dipole-transition paths. The reduction of enhancement factors due to ionization effects is also qualitatively analyzed. |
(创新港)
