Université de Neuchâtel

New frontiers of ultrafast thin-disk laser oscillators for applications in metrology and the generation of THz and XUV radiation

Modsching, Norbert Paul ; Südmeyer, Thomas (Dir.)

Thèse de doctorat : Université de Neuchâtel, 2019.

Ultrafast laser systems find application as versatile tool in industry and science. Ultrafast laser systems based on Ti:sapphire – the workhorse in ultrafast science – operate typically at kHz repetition rates and benefit from the available broad gain bandwidth for the direct generation of sub 100-fs pulse durations. However, thermal effects in the gain medium due to a high quantum defect...

Université de Neuchâtel

Structural and spectroscopic investigation of the Yb/Al(001) interface in the submonolayer coverage range

Fasel, Roman ; Aebi, Philipp ; Osterwalder, Jürg ; Schlapbach, Louis

In: Surface Science, 1997, vol. 394, no. 1-3, p. 129-143

The formation of submonolayer Yb overlayers on Al(001) has been studied by angle-scanned full-hemispherical X-ray photoelectron diffraction and angle-resolved ultraviolet photoelectron spectroscopy. It is shown that different phases, as observed by low-energy electron-diffraction, are formed up to a coverage of 0.5 ML where the first Yb layer is completed. An intimate connection of spectroscopic...

Université de Neuchâtel

Surface alloy formation and interdiffusion in (√5 × √5)R27°-Yb/Al(001): a combined low-energy electron diffraction and X-ray photoelectron diffraction study

Fasel, Roman ; Gierer, M. ; Bludau, H. ; Aebi, Philipp ; Osterwalder, Jürg ; Schlapbach, Louis

In: Surface Science, 1997, vol. 374, no. 1-3, p. 104-116

We have investigated the atomic structure of (√5 × √5)R27°−Yb/Al(001) by low-energy electron diffraction and angle-scanned full-hemispherical X-ray photoelectron diffraction. Quantitative agreement between the results from the two methods is obtained. We find that the Yb atoms occupy substitutional sites, thus removing every fifth surface Al atom. The residual first-layer Al atoms are...