ISBN 978-3-8439-2978-3

978-3-8439-2978-3, Reihe Physik

Hannes M. Gorniaczyk
Single Photon Transistor mediated by electrically tunable Rydberg-Rydberg Interactions

217 Seiten, Dissertation Universität Stuttgart (2016), Hardcover, A5

Zusammenfassung / Abstract

Modern information technology is based on light as information carrier. Data is transmitted through optical fibers over long distances with huge bandwidths. It is a long-standing goal in nonlinear optics to develop materials and devices that allow optical data processing without interfacing it to electronic circuits which are subject to loss and time lag.

In this work, a versatile quantum optics experiment was built demonstrating an optical transistor which toggles its state by the input of the smallest energy unit possible: one gate photon. Mediated by interaction between Rydberg atoms, this single gate photon immediately affects the optical properties of the medium, a cloud of ultra-cold atoms, such that the transmission of a laser beam is reduced by hundreds of source photons through Rydberg blockade of electromagnetically induced transparency (EIT).

The effective interaction between a gate photon and the source photons can be tuned by applying constant electric fields. That way, a strong enhancement of the optical nonlinearity is obtained if the states are Stark-shifted to Förster resonances. Conversely, the interaction strength can be minimized at electric fields between resonances.

By reading out the stored gate excitation after scattering source photons, coherence properties of this quantum state are studied.

To sum up, our results are a distinct proof that huge optical nonlinearities can be generated with Rydberg-EIT. Our highly tunable optical transistor could advance classical information technology. The study of coherence properties is an important step towards the implementation of photonic quantum gates.