Hans Hepach

Hans Hepach
Early Stage Researcher
University of Vienna

Academic background

12/2015 – present: PhD student in Physics at University of Vienna

10/2014 – 12/2015: MSc in Physics at University of Vienna: Design and Characterisation of a Low-Noise, Audio-Band Photodetector at 100mW Optical Power

10/2013 – 10/2014: Studies of Physics at University of Leipzig

10/2009 – 10/2013: BSc at Humboldt University Berlin


Current research topic (PhD)

I am working on a project trying to demonstrate the gravitational attraction between two small (milligram-sized) masses.

By using micromechanical oscillators, it should be possible to best the current record for purely gravitational interaction between two masses by about two to three orders of magnitude. The challenge lies in the combination of sophisticated vibrational isolation of source and test mass against each other as well as the environment while driving them periodically and maintaining a high readout precision.

The first step has been the design of a photodetector able to handle the amount of optical power needed to ensure required sensitivity of the readout scheme. The next steps include finalising simulations and building the mechanical parts of the experiment.

In the future, reducing the size of test and source mass may pave the way towards experiments combining quantum systems via their own gravitational attraction and/or lead to new high precision measurements of the gravitational constant.