Tunable isolated attosecond pulse generation by sub-cycle optical pulses from a parametric waveform synthesizer

We present direct isolated attosecond pulse (IAP) generation with waveform controlled non-sinusoidal pulses generated by parametric waveform synthesis. Pulses as short as 0.6 optical cycle are generated by the synthesis of two broadband OPA channels and span the range from 650 nm to 2.2 µm with millijoule-level energy. Driving HHG with such a source directly generates IAPs without the need of additional gating methods. The synthesis parameters (CEP, relative phase) allow for intricate tuning of the IAP spectrum and pulse duration confirmed with attosecond streaking