Dr. David Hunger, Max-Planck-Institut für Quantenoptik and Department of Physics, Ludwig-Maximilians-University Munich (LMU)

We are inviting applications for a PhD position within the Cavity Quantum Optics project in the group of Prof. T.W. Hänsch at the LMU Munich. Our group is performing experiments with fiber-based optical micro-cavities as a new tool for solid-state based cavity QED and ultrasensitive microscopy. We focus on a particularly promising cavity design which relies on laser-machined optical fibers coated with high reflective dielectric mirrors.  In this way we have realized Fabry Perot cavities with microscopic mode volumes (<20µm³) and very high quality factors (>10⁷).

The reflection of light between the mirrors gives rise to multiple interactions of probe light with a sample inside the cavity, accumulating the effect of the sample on the light. This enhances sensitivity by several orders of magnitude compared to a free-space situation, and thereby opens the way to study individual nanoscale objects with small extinction cross sections. Raster-scanning a sample through the cavity mode permits to investigate the optical properties of samples with high spatial resolution, the narrow optical resonances of the cavity enable high spectral resolution as well as high sensitivity for dispersive interactions.

Starting from an existing proof of principle experiment we want to develop the technique towards a versatile microscopy scheme and use it for a broad variety of applications, including e.g. spectroscopy of individual nanoparticles, absorption spectroscopy of single quantum emitters, and detection of weakly absorbing macromolecules. The project has a multidisciplinary character and offers ample possibilities for collaborations, in particular within the excellence cluster Nanosystems Initiative Munich (NIM) and the Center for NanoScience (CeNS).

We seek for a creative and motivated individual to advance this research project. Experience in the fields of e.g. quantum optics, single molecule spectroscopy, or super resolution microscopy is advantageous but not a necessity.

More information about the group:
Dr. Hunger's website