Adjustment of an optical chip with a quantum light source.

Integrated Quantum Systems

Dr. Tobias VOGL
Adjustment of an optical chip with a quantum light source.
Image: Jens Meyer (University of Jena)
Dr. Tobias Vogl. Dr. Tobias Vogl. Image: Private.

Dr. Tobias VOGL

Phone: +49 3641-9-47992

Dr. Tobias Vogl is the head of the junior research group Integrated Quantum Systems located at the Institute of Applied Physics. He is also speaker and coordinator of the QUICK3 consortium, an international research program that develops quantum photonic components for secure communication with small satellites. In 2021, he was awarded the INNOspace Masters Award by the DLR Space Administration.

The Integrated Quantum Systems research group aims to explore and understand light-matter-interaction and quantum properties of 2D materials. Fluorescent point-like defects in hexagonal boron nitride (hBN) have shown to emit pure single photons with a high luminosity at room temperature. We enhance these quantum emitters by coupling them to resonant optical systems and integrated photonics. We partially focus on fundamental research to better understand the nature of the emitters, which enables us to tailor their photophysical properties. However, we also explore them already for applications in the field. Our interests include quantum communication, quantum computation, interferometry, as well as quantum sensing and super-resolution nanoscopy.

A highlight of our current research efforts is the QUICK3 space mission, with which we develop a satellite payload with a quantum light source in orbit. Satellite-based quantum links are crucial for a future quantum-secured internet, as they allow us to bridge long distances where optical fibers cannot be used. The project is embedded into an international collaborative network that supply different components of our satellite with the launch scheduled for 2024.

Research Areas

The research of Dr. Vogl targets the utilization of quantum emitters in 2D materials for optical quantum technologies. Current research interests include:

  • Single photon sources
  • Quantum communication
  • Quantum computation
  • Space systems
  • Integrated photonics
  • Linear and nonlinear light-matter-interaction
  • Fundamental aspects of quantum mechanics
  • Quantum imaging

Teaching Fields

Dr. Vogl is devoted to including early career scientists in modern research topics. Besides the supervision of students on all levels, current courses include:

  • Rigorous Numerical Simulation of Quantum Photonic Nanostructures

Research Methods

Our laboratory is equipped with state-of-the-art infrastructure for the fabrication and characterization of 2D materials, integrated waveguide optics, and quantum photonic technologies, which includes:

  • Precision alignment and transfer setups for atomically thin materials
  • Femtosecond photoluminescence spectroscopy
  • HBT-, phase-shift, and multi-path interferometers
  • AFM and dual-beam SEM-FIB
  • Supercomputing cluster for numerical modeling
  • Quantum communication sender and receiver units

Recent Research Results

Quantum theory is the foundation of modern physics, and its predictions are in remarkable agreement with experiments. The framework of quantum physics, like the mathematical structure of the measurement process, however, relies on postulates that need experimental verification. An example for such postulate is Born’s rule. Any deviation from Born’s rule results in interference between more than two paths and can thus be tested using a multi-path interferometer. We have demonstrated that by using a true single photon source based on hBN [1, 2], we can increase the interferometric sensitivity of our three-path interferometer compared to conventional laser-based light sources by fully suppressing the detector nonlinearity [3]. We also measured an interference visibility of 98.58% for our single photons emitted from hBN at room temperature, which provides a promising route for using the hBN platform as light source for phase-encoding schemes in quantum key distribution.

In another recent experiment we have space-qualified laser-written waveguides for use in space environments, where we have found a high tolerance to the harsh radiation environments and an insensitivity to temperature fluctuations [4]. Since our single photon source can be directly interfaced with waveguiding structure [5] and is space qualified as well [6], we are able to employ these robust and compact quantum light sources in space environments on satellites.

[1] T. Vogl et al., ACS Photonics 5, 2305-2312 (2018).
[2] T. Vogl et al., ACS Photonics 6, 1955-1962 (2019).
[3] T. Vogl et al., Phys. Rev. Res. 3, 013296 (2021).
[4] S. Piacentini et al., Laser Photon. Rev. 15 2000167 (2021).
[5] T. Vogl et al., J. Phys. D: Appl. Phys. 50, 295101 (2017).
[6] T. Vogl et al., Nat. Commun. 10, 1202 (2019).

link to the Vogl Group at the Institute of Applied Physics