Research

The MLR-TT sensor

I have been leading the micro-lens ring, tip-tilt sensor (MLR-TT sensor) project. This concept has first been introduced by Dietrich & Harris, et al. 2017 (doi:10.1364/OE.25.018288) featuring a micro-lens array (MLA) on top of a single-mode, multi-code fiber and I subsequently optimized and implemented a modified version with a micro-lens ring coupling light into multi-mode fibers (MMFs) for sensing while coupling into a SMF for science observation.
For related publication, please see here.

Here follow some impressions…

Telescope beam entering the MLR-TT sensor (artist impression)
Close-up photograph of the MLR on the fiber face (Hottinger et al., 2019, Proceedings of AO4ELT6, arXiv:1912.09537)
Simple overview of the working principle. As the incoming beam continues to become misaligned, the coupling into the outer MMFs changes allowing a reconstruction of the centroid position. (Hottinger, 2019, presented at AO4ELT6)
Integrating the MLR-TT sensor’s optical and electronic enclosure (black, right) to the iLocater acquisition camera (blue, left) at the LBT in 2019.

Laboratory development

I have been involved in the Königstuhl Observatory Opto-mechatronics Laboratory (KOOL), which is run at Max-Planck-Institute for Astronomy (MPIA, PI Jörg-Uwe Pott) in Heidelberg, Germany. KOOL is a joint project of the MPIA, the Landessternwarte (University Heidelberg), and the Institute for System Dynamics (University Stuttgart).

KOOL is an adaptive optics (AO) testbed that allows both disturbing and correction of a telescope simulator’s pupil. I have added an infrared beam path and a fiber coupling arm for single-mode fiber measurements and system development.

KOOL fiber coupling arm incl. the MLR-TT sensor.

Planet formation theory

In my master thesis I used a hydrodynamic Riemann solver (PLUTO v4.2, Mignone et al. 2007) to simulate warped protoplanetary disks and investigated the experienced numerical effects.

Hydrodynamic simulation of warped protoplanetary disks. The two disks have a initial misaligned configuration but both feel a numerical torque acting to align them to each other and to the grid.
Simulated with PLUTO, visualized with Paraview. (M.Sc. Thesis: A Numerical Investigation of Warped Protoplanetary Disks at MPIA under supervision of Hubert Klahr; Hottinger, 2016)