中文摘要：

我们理论研究了正交偏振双色激光场作用下的高次谐波发射和孤立阿秒脉冲的产生．当Y方向加一束中红外激光脉冲（12．5fs／2000nm），x方向加一束强度较弱的激光脉冲（12fs／800nm）时，我们得到从250eV到350eV的超连续谐波平台，在平台范围内叠加50eV的谐波，可以得到一个脉宽约为97as的孤立阿秒脉冲．通过时频分析，我们解释了高次谐波发射的物理机制．

英文摘要：

We theoretically investigate the high-order harmonic generation and single attosecond pulse generation in an orthogonally polarized two-color laser field, which is synthesized by a mid-IR pulse （12. 5 fs/2000 nm） in y-component and a much weaker （12fs/800nm） pulse in x-component. We find that the supercontinuum harmonic plateau is formed from 250 eV to 350 eV and an isolated attosecond pulse with a duration of about 97 as can be obtained when superposing a region of 50 eV. We investigate the emission time of the harmonics in terms of the time-frequency analysis to illustrate the physical mechanism of high-order harmonic generation.