TY  - JOUR
A1  - Vorholt, Christian
A1  - Wittrock, Ulrich
T1  - Single-frequency oscillation of thin-disk lasers due to phase-matched pumping
JF  - Opt. Expr.
N2  - We present a novel pump concept that should lead to single-frequency operation of thin-disk lasers without the need for etalons or other spectral filters. The single-frequency operation is due to matching the standing wave pattern of partially coherent pump light to the standing wave pattern of the laser light inside the disk. The output power and the optical efficiency of our novel pump concept are compared with conventional pumping. The feasibility of our pump concept was shown in previous experiments.
KW  - diode-pumped laser
KW  - solid-state laser
KW  - ytterbium laser
Y1  - 2017
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:hbz:836-opus-10258
VL  - 25
SP  - 21388
EP  - 21399
ER  - 
TY  - JOUR
A1  - Wittrock, Ulrich
T1  - Limitations? What Limitations? Prof. Ulrich Wittrock, head of the Photonics Laboratory at the Münster University of Applied Sciences, seeks out the ultimate boundaries of laser technology
JF  - Laser Community - the laser magazine from Trumpf
Y1  - 2014
VL  - 02:14
ER  - 
TY  - JOUR
A1  - Wittrock, Ulrich
A1  - Vorholt, Christian
T1  - Spatial hole burning in Yb:YAG thin-disk lasers
JF  - Appl. Phys. B
N2  - The spatially varying intensity in a standing wave resonator leads to spatial hole burning in the gain medium of a laser. The spatial hole burning changes the gain of different longitudinal modes and can thus determine the optical spectrum of the laser. We simulate this longitudinal mode competition in standing wave resonators of thin-disk lasers. The resulting optical spectra of the laser are compared to measured optical spectra. We examine two types of resonators: I-resonators and V-resonators with different angles of incidence. In V-resonators, the non-normal incidence of the laser beam on the disk lifts the degeneracy of the polarization. Experiments show that the slight gain advantage for the p-polarization does not lead to polarized emission. For both types of resonators, the measured spectra are in good agreement with the simulated ones. The simulations allow to study the influence of spectral intra-cavity losses on the optical spectrum of a thin-disk laser.
Y1  - 2015
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:hbz:836-opus-8234
VL  - 120
SP  - 711
EP  - 721
ER  -