Harmonic generation inside a non-collinear optical parametric oscillator

• Applicant: Professor Dr. Uwe Morgner
• Subject Area: Optics, Quantum Optics and Physics of Atoms, Molecules and Plasmas
• Term: since 2020
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 450606493

In the preliminary work, the non-collinear phase-matched parametric oscillator (NOPO) was investigated in many ways. Among other things, a dispersion-managed NOPO (DMNOPO) concept was presented, which opens up a new approach to power scaling of pulses of a duration of a few optical cycles from an oscillator. The DM-NOPO can be easily scaled via the pump laser and is ultimately only limited by component damage. In the present application the further power scaling by a new thin-disk laser oscillator as a pump laser shall be pursued. The pulses circulating in the DMNOPO are focused into a gas jet at a point in the resonator where they have the few-cycle duration. There, strong-field effects at oscillator repetition rates can and shall be studied. A novel double pulse topology enables the non-collinear generation of radiation in noble gases and their efficient extraction. The aim is to study the generation of harmonic radiation, initially of a lower order and later of a higher order. Of particular interest is the irradiation of laser pulses with elliptical polarization into the target. The preliminary work has shown that interesting information about the ionization dynamics in the sense of an optical attoclock can be extracted from the resulting polarization state of the harmonics. This work paves the way for the generation of high order harmonics and the demonstration of a real mode comb in the XUV spectral range with resonantly enhanced few-cycle pulses.

• DFG Programme: Research Grants