Archiviertes Physik-Kolloquium:

20. Apr. 2017, 16:00 Uhr, Gebäude NW1, Raum H3

Why I am optimistic about semiconductor quantum dot based entangled photon sources

Prof. Dr. Fei Ding, Institute for Solid State Physics, Leibniz University Hannover

Entangled photon sources are playing a crucial role in photonic quantum information science. Self-assembled semiconductor quantum dots (QDs) are among the most promising sources for on-demand generation of entangled photons. Compared to other candidate systems, QDs have an undeniable advantage of being compatible with mature semiconductor technologies. However, due to the self-assembled growth nature, the physical properties of QDs are highly random. To date the QD based entangled photon sources are far from being ideal and several critical challenges need to be solved for practical applications. In this talk I will review our recent efforts in developing a QD-based entangled photon source with the best possible performances. A large ensemble of as-grown entangled photon emitters can be obtained with a yield close to 100% and high entanglement fidelity (up to 0.9). The wavelength mismatching between different sources can be solved by using a unique strain tuning technique developed in our group. The superior properties of these sources, combined with the demonstrations of electrical injection and on-chip integration, will eventually make the semiconductor QDs an ideal entangled photon source for the practical quantum applications. References: (* corresponding author) [1] F. Ding*... O. G. Schmidt, Phys. Rev. Lett. 104, 067405 (2010) [2] F. Ding*... O. G. Schmidt, Nano Lett. 10, 3453 (2010) [3] J. Zhang...F. Ding*, O. G. Schmidt, Nano Lett. 13, 5808 (2013) [4] Y. Huo...F. Ding... O. G. Schmidt, Nature Phys. 10, 46 (2014) [5] J. Zhang...F. Ding*, O. G. Schmidt, Nature Commun. 6, 10067 (2015) [6] Y. Chen...F. Ding*, O. G. Schmidt, Nature Commun. 7, 10387 (2016) [7] R. Keil, M. Zopf…F. Ding*, O. G. Schmidt, Nature Commun. accepted (2017)