Callinstr. 38, room 17
+49 511 762-14144
Dennis joined the group in August 2017 as a PhD student. He works on generation, detection, and application of squeezing at high frequencies. Squeezers not only generate squeezing at frequencies within the resonance bandwidth of their cavities (base band) but also at other longitudinal modes. This allows the measurement of squeezing at multiples of the free-spectral-range (FSR) of the squeezing cavity.
Currently, Dennis finishes together with Jonas an experiment on precision spectroscopy started by Timo. The idea is to employ squeezing at the first FSR (~200 MHz) to reduce the quantum noise in a spectroscopy measurement.
Subsequently, he will utilise the high-frequency squeezer for experiments in the field of quantum information. A squeezer is based on a parametric down-conversion process. This process generates pairs of entangled photons. If these are non-degenerate, i.e. have different polarisation or frequency, they can be spatially split. This allows the generation of Einstein-Podolsky-Rosen states with a wide range of applications. We plan to conduct experiments such as measurement-induced entanglement, entanglement swapping and quantum teleportation in space and frequency.
Beforehand, Dennis was pursuing his master thesis in the laser group led by Prof. Benno Willke at the same institute. He worked on a nonclassical laser power stabilisation experiment. By the injection of amplitude-squeezed vacuum states, he demonstrated the first laser power stabilization below the classical shot noise limit. The results have been published in Physical Review Letters.