Triggered sources of entangled photons play crucial roles in almost any existing protocol of quantum information science. The possibility to generate these non-classical states of light with high speed and using electrical pulses could revolutionize the field. Entangled-light-emitting-diodes (ELEDs) based on semiconductor quantum dots (QDs) are at present the only devices that can address this task 5. However, ELEDs are plagued by a source of randomness that hampers their practical exploitation in the foreseen applications: the very low probability (~10-2) of finding QDs with sufficiently small fine-structure-splitting for entangled-photon-generation. Here, we overcome this hurdle by introducing the first strain-tunable ELEDs (S-ELEDs) that exploit piezoelectric-induced strains to tune QDs for entangled-photon-generation. We demonstrate that up to 30% of the QDs in S-ELEDs emit polarization-entangled photon pairs with entanglement-fidelities as high as f+ = 0.83(5). Driven at the highest operation speed of 400 MHz ever reported so far, S-ELEDs emerge as unique devices for high-data rate entangled-photon applications.
@article{arxiv.1505.03026,
title = {Strain-tunable entangled-light-emitting diodes with high yield and fast operation speed},
author = {Jiaxiang Zhang and Johannes S. Wildmann and Fei Ding and Rinaldo Trotta and Yongheng Huo and Eugenio Zallo and Daniel Huber and Armando Rastelli and Oliver G. Schmidt},
journal= {arXiv preprint arXiv:1505.03026},
year = {2016}
}
Comments
28 pages in total, including supplementary information. 5 figures