Tailoring attosecond pulse trains generated by intense femtosecond two-color fields

The spectral components of high-harmonic generated attosecond pulse trains (APTs) driven by a one-color driving field have been reported extensively in the literature. It is well known that the attochirp of the spectral phase limits the achievable level of synchronization of the frequencies making up the pulse. On the contrary, studies on the spectral phases of APTs generated by a multi-color field have been sparse so far, despite the potential such APTs could have for attosecond experiments.



In this work, we show that the spectral phases of APTs generated by intense two–color femtosecond fields can be tuned by varying both the intensity ratio and the phase between the two components of the driving field. We found that the spectral phases exhibit high tunability for an intensity ratio between the two colors of the driving field in the range of 0.05% to 5%. We show that the spectral phases can be manipulated in order to produce either one or two attosecond pulses per optical cycle of the driving field.