Preservation of CEP upon generation of XPW pulses

Upon efficient generation of cross-polarized wave (XPW) in a cubic crystal via achromatic χ
⁽³⁾
process, the XPW pulses are polarized in the orthogonal direction. XPW generation has demonstrated its ability to filter amplified spontaneous emission out of a high power femtosecond pulse, thereby increasing its temporal contrast and also to broaden the pulse spectrum by more than a factor of two [1,2]. Furthermore, in case of energetic few-cycle pulses, the laser-matter interaction depends on the carrier envelope phase (CEP) of the pulses. Hence it is essential to stabilize the intrinsic CEP drift between successive pulses from the laser. If the XPW filter is used in the laser chain it is important to demonstrate that it does not deteriorate the CEP stability of the system. In this presentation, we give clear experimental evidence that the CEP is preserved upon the XPW process.