Non-linear Quantum optics

Welcome to our group „Non-linear quantum optics” at the IQP of the University of Hamburg!

We have been researching the applicability of squeezed and entangled laser (Wikipedia-link) and new concepts and technology for measuring gravitational waves.

In 2010 (then still at the Leibniz University of Hannover), the group of Professor Roman Schnabel designed and built the world’s first fully automated squeezed laser. This laser has been in uninterrupted use in the gravitational-wave detector GEO600¹.

¹[The LSC, A gravitational wave observatory operating beyond the quantum shot-noise limit, Nature Physics 7, 962 (2011)].

15 dB squeezed light

The Group has been producing the highest squeeze factors since 2008.

[H. Vahlbruch, M. Mehmet, K. Danzmann, R. Schnabel, Detection of 15dB squeezed states of light and their application for the absolute calibration of photo-electric quantum efficiency, Phys. Rev. Lett. 117, 110801 (2016)]

Review article on squeezed light

[R. Schnabel and A. Schönbeck, The “Squeeze Laser”, IEEE Transactions on Quantum Engineering: Quantum Sensing and Metrology 3, 3500209 (2022)]

[R. Schnabel, The success story of squeezed light, Conf. Proceedings Moriond Gravitation 2022]

[R. Schnabel, Einstein would be doubly amazed, Physics Today, 75 (8), 46-51Institut für Quan (August 2022)]

[R. Schnabel, Einstein wäre doppelt verblüfft, PHYSIK in unserer Zeit 52, 130 (2021)] 

[R. Schnabel, Squeezed states of light and their applications in laser interferometers, Physics Reports 684, 1-51 (2017)]

[R. Schnabel, N. Mavalvala, D.E.McClelland, P.K.Lam, Quantum metrology for gravitational wave astronomy, Natur Communications 1, 121 (2010)]

Spinn-off for squeezed light

In February 2023, the group founded the world's first company to sell squeeze lasers: Noisy Labs GmbH (spin-off of the University of Hamburg).

Technology Transfer of the Department of Physics

Knowledge transfer of the Department of Physic

Overview of the research topics