Freiburg 2019 – wissenschaftliches Programm
FM 32.4: Talk
Dienstag, 24. September 2019, 15:00–15:15, 1010
A cavity-based optical antenna for color centers in diamond — •Philipp Fuchs, Thomas Jung, and Christoph Becher — Universität des Saarlandes, Fakultät NT - FR Physik, Campus E2.6, 66123 Saarbrücken
Color centers in diamond, e.g. the nitrogen (NV), silicon (SiV) or recently the tin (SnV) vacancy center, have become very promising candidates for the implementation of stationary qubits in quantum communication settings. One of the most challenging problems when working with these defects is the low rate of collectible photoluminescence (PL) out of unstructured diamond material. Because of total internal reflection at the diamond-air-interface, this problem cannot be solved simply by using high NA objectives and the collectible PL rate is limited to a few percent of the total PL rate.
Here, we present a simple but efficient design of a monolithic Fabry-Pérot-cavity based on thin (< 1 µm) single crystal diamond membranes, fabricated in commercially available, high purity diamond material via reactive ion etching. By applying appropriate metallo-dielectric coatings, we enable the cavity to work as an optical antenna, enhancing both the coupling of the excitation light to the color center as well as the outcoupling of the PL, while introducing also a moderate Purcell enhancement. Saturation measurements show that the the collectible PL rate of single SnV centers can easily be increased by more than an order of magnitude for a large fraction of emitters inside the membrane compared to unstructured diamond films.