We have studied the pulse shaping of the chirped laser pulse by the reflection from the linear plasma density ramp. The temporal profile of the frequency in the chirped laser pulse manifests in distinct apparent reflection points inside the plasma having a linear density profile. The higher frequency component reflects from the deeper portion of the plasma as compared to the lower frequency component. These frequency-dependent variations in apparent reflection points introduce a natural phase lag, and the reflected pulse shortens, without compromising on the actual bandwidth and the energy of the pulse. Under optimum conditions, we find the peak field amplitude of the reflected pulse to be almost 2 times that of the incident pulse. We have deduced the condition for the efficient generation of the reflected pulse in terms of the incident pulse and target parameters. The higher harmonic generation by Helium atom through the above mentioned reflected pulse is studied by numerically...

中文翻译：

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plasma激光从等离子体的反射及其在阿秒脉冲产生中的应用

我们已经通过线性等离子体密度斜坡的反射研究了laser激光脉冲的脉冲整形。laser激光脉冲中的频率的时间轮廓表现在具有线性密度轮廓的等离子体内部明显的明显反射点上。与低频分量相比，高频分量从等离子体的较深部分反射。这些视在反射点的频率相关变化会引入自然相位滞后，并且反射脉冲会缩短，而不会影响脉冲的实际带宽和能量。在最佳条件下，我们发现反射脉冲的峰值场振幅几乎是入射脉冲的两倍。我们根据入射脉冲和目标参数推导了有效产生反射脉冲的条件。通过数值研究了氦原子通过上述反射脉冲产生的高次谐波...