The above-threshold detachment of negative ions in half-cycle laser field

We study partial detachment rate and photodetachment asymmetry of F− detached by half-cycle linearly polarized laser field using numerical simulation. Similar to photodetachment for negative ions in few-cycle laser fields, we find that partial detachment rates of a couple opposite directions in the above-threshold detachment of F− are not equal, the detachment is asymmetric. Furthermore, the photodetachment asymmetry degree increases with carrier-envelop phase (CEP) as the peak laser intensity becoming stronger or the pulse width becoming shorter. The maximal asymmetry degree is stronger with higher laser intensity. We confirm the effect of the CEP, laser intensity and pulse width on the above-threshold detachment of F− in half-cycle laser fields. It provides a possible way to determine the CEP of half-cycle laser fields by measuring detached photoelectrons.