Proposal for carrier-envelope-phase stable single-cycle pulse generation in the mid-infrared - extreme-ultraviolet range

A robust method for producing half-cycle - few-cycle pulses in mid-infrared to extreme ultraviolet spectral ranges is proposed. It is based on coherent undulator radiation of relativistic ultrathin electron layers, which are produced by microbunching of ultrashort electron bunches by a TW power laser in a modulator undulator. According to our numerical calculations it is possible to generate as short as 10 nm long electron layers in a single-period modulator undulator having an undulator parameter of only K=0.25 and which is significantly shorter than the resonant period length. By using these electron layers the production of carrier-envelope-phase stable pulses with up to a few nJ energy and down to 30 nm wavelength and 70 as duration is predicted.