Our group focuses on efficient light-matter interfaces in the fields of solid-state quantum optics and sensing. Quantum emitters are not only key for applications such as sensing but play an essential part in new developments in quantum technology. Photons on the other hand have proven excellent carriers of information. They can be manipulated to high precision, are well shielded from decoherence by the environment and can be guided for long distances with low loss using optical fibers. With the aim to realise small and scalable systems that can be used as constituents in photonic quantum networks or as precise sensors, solid state quantum emitters have moved into focus. They are able to provide similar level structures compared to isolated atoms but can be more easily manipulated and integrated in different kinds of photonic networks or nanostructures. The guided modes of nanophotonic waveguides exhibit a pronounced evanescent field that allows for sensitive detection of even individual molecules or atoms in their surrounding. These waveguides can also be combined with microcavities to further enhance the light-matter interaction.

Solid-state quantum optics

We are now working towards an efficient light-matter interface using nanophotonic waveguides on chips and solid-state quantum emitters such as molecules in solids or colour centers in hexagonal Boron Nitride within the framework of the FETOpen project ErBeStA, opens an external URL in a new window . As many solid-state quantum emitters require cryogenic temperatures to freeze out the phonons of the host system and avoid dephasing and inelastic scattering, most experiments so far have been conducted below 4 K. We were recently able to demonstrate that an alignment-free microcavity based on fiber Bragg gratings and an optical nanofiber can be used at cryogenic temperatures and may provide a promising platform for a strong light-matter interface. In addition we are also planning to move the field of solid-state quantum optics to room temperature.

Quantum emitters in hBN are a promising system to achieve this goal and we are currently working on a new experiment that was recently funded by an ESQ Discovery Grant, opens an external URL in a new window.
We are very happy that our work on 2D materials has attracted more funding. Our new project PhoQus2D is funded by the FFG, opens an external URL in a new window and will be conducted in collaboration with the group of Nanomaterials Synthesis and Integration, opens an external URL in a new window of the TU Wien.
Recently, Dr. Sarah Skoff has also been awarded a prestigious Elise-Richter research fellowship, opens an external URL in a new window which paves the way for more new exciting work on quantum emitters in 2D materials.

Detection of nanoplastic

In an effort to apply methods and tools from quantum optics in environmental sensing, we have also started working on detection methods for nanoplastic. The global increase in plastic production and disposal has resulted in large amounts of plastic that end up in our environment. Fragmentation of this plastic waste in the environment leads to micro- and nanoplastics which are dispersed even more easily and are harder to contain. Nanoplastics in particular are very difficult to detect because of their small size but can cause great harm as these particles can even cross the blood-brain barrier in living organisms and enter the placenta. Efficient light-matter interactions are key for detection and thus we are studying plasmonics and other tools from nanophotonics to make these tiny particles visible.

For our research we are always looking for motivated students or PostDocs to join us in our efforts to further advance solid-state quantum optics and apply quantum technology and nanophotonics for sensing applications.

Team

Group leader:
Dr. Sarah M. Skoff

Scientific Assistant:
Helmut Hörner
Ambika Shorny

Master- and Projectstudents:
Alexander Becker
Alexander Brendt
Fritz Steiner
Thomas Hofmann
Paul Mühlgassner