Post Doctoral Researcher Callinstr. 36, room 124 jonas.junker@aei.mpg.de +49 511 762-17073

Jonas joined the group in December 2016 as a PhD student and defended his thesis in February 2023. His cumulative thesis shows different approaches to utilising squeezed states for high-precision metrology. The results are published in three articles.

The first article deals with a particular high-frequency and phase-modulated squeezed state that can be applied to spectroscopy. It shows that a small phase signal generated in a cavity can be resolved below show noise by using a squeezed quantum state.

In the second article, the authors demonstrate that a detuned single-mode squeezer is capable of generating a frequency-dependent squeezed state. This particular squeezer could be used as an approximate effective-negative mass oscillator, e.g., for coherent quantum noise cancellation.

The third article deals with a new approach to detecting and characterising a two-mode squeezed state using a single polarisation-sensitive homodyne detector. The approach makes it possible to reconstruct the full covariance matrix, which fully characterises the entangled state.

After his PhD, Jonas continues working as a post-doctoral researcher in our group. Currently, he focuses on building a particular five-mirror cavity together with Johny. In this cavity, a two-mode down-conversion process and coupling between the polarisation modes occur. The system will be used as an effective-negative mass oscillator for coherent quantum noise cancellation (CQNC).

Publications:
Jonas Junker, Dennis Wilken, Daniel Steinmeyer, and Michèle Heurs, “Reconstructing Gaussian bipartite states with a single polarization-sensitive homodyne detector,” Opt. Express 30, 33860-33868 (2022), DOI: https://doi.org/10.1364/OE.465186
Jonas Junker, Dennis Wilken, Nived Johny, Daniel Steinmeyer, and Michèle Heurs “Frequency-Dependent Squeezing from a Detuned Squeezer”, Physical Review Letters (Vol. 129, Issue 3). (2022), DOI: https://doi.org/10.1103/physrevlett.129.033602
Jonas Junker, Dennis Wilken, Elanor Huntington, and Michèle Heurs, “High-precision cavity spectroscopy using high-frequency squeezed light,” Opt. Express 29, 6053-6068 (2021), DOI: https://doi.org/10.1364/OE.416713
Jonas Junker, Patrick Oppermann, and Benno Willke, “Shot-noise-limited laser power stabilization for the AEI 10  m Prototype interferometer,” Opt. Lett. 42, 755-758 (2017), DOI: https://doi.org/10.1364/OL.42.000755

News:
February 2023: Jonas defended his PhD thesis
December 2022: Jonas handed in his PhD thesis