Control of quantum paths in the multicycle regime and efficient broadband attosecond pulse generation

We theoretically investigate the broadband isolated attosecond generation in a two-color multicycle laser pulse. It is shown that quantum path selection can be realized and then a sub-100-as isolated attosecond pulse is straightforwardly obtained. By adding an UV attosecond pulse to the synthesized two-color field, the continuous harmonic yield is significantly enhanced by 2 orders and the bandwidth is further broadened, which is beneficial to the efficient generation of a sub-100-as isolated attosecond pulse. (C) 2008 Optical Society of America