- Eich, S;
- Stange, A;
- Carr, AV;
- Urbancic, J;
- Popmintchev, T;
- Wiesenmayer, M;
- Jansen, K;
- Ruffing, A;
- Jakobs, S;
- Rohwer, T;
- Hellmann, S;
- Chen, C;
- Matyba, P;
- Kipp, L;
- Rossnagel, K;
- Bauer, M;
- Murnane, MM;
- Kapteyn, HC;
- Mathias, S;
- Aeschlimann, M
Time- and angle-resolved photoemission spectroscopy (trARPES) using femtosecond extreme ultraviolet high harmonics has recently emerged as a powerful tool for investigating ultrafast quasiparticle dynamics in correlated-electron materials. However, the full potential of this approach has not yet been achieved because, to date, high harmonics generated by 800 nm wavelength Ti:Sapphire lasers required a trade-off between photon flux, energy and time resolution. Photoemission spectroscopy requires a quasi-monochromatic output, but dispersive optical elements that select a single harmonic can significantly reduce the photon flux and time resolution. Here we show that 400 nm driven high harmonic extreme-ultraviolet trARPES is superior to using 800 nm laser drivers since it eliminates the need for any spectral selection, thereby increasing photon flux and energy resolution to < 150 meV while preserving excellent time resolution of about 30 fs. © 2014 The Authors.