Title: |
Indistinguishable MHz-narrow heralded photon pairs from a whispering gallery resonator |
Authors: |
Huang, Sheng-Hsuan, Dirmeier, Thomas, Shafiee, Golnoush, Laiho, Kaisa, Strekalov, Dmitry V., Aiello, Andrea, Leuchs, Gerd, Marquardt, Christoph |
Publication Year: |
2024 |
Collection: |
Physics (Other) Quantum Physics |
Subject Terms: |
Quantum Physics, Physics - Optics |
More Details: |
Hong-Ou-Mandel interference plays a vital role in many quantum optical applications where indistinguishability of two photons is important. Such photon pairs are commonly generated as the signal and idler in the frequency and polarization-degenerate spontaneous parametric down conversion~(SPDC). To scale this approach to a larger number of photons we demonstrate how two independent signal photons radiated into different spatial modes can be rendered conditionally indistinguishable by a heralding measurement performed on their respective idlers. We use the SPDC in a whispering gallery resonator, which is already proven to be versatile sources of quantum states. Its extreme conversion efficiency allowed us to perform our measurements with only \qty{50}{nW} of in-coupled pump power in each propagation direction. The Hong-Ou-Mandel interference of two counter-propagating signal photons manifested itself in the four-fold coincidence rate, where the two idler photons detection heralds a pair of signal photons with a desired temporal overlap. We achieved the Hong-Ou-Mandel dip contrast of \(74\pm 5\%\). Importantly, the optical bandwidth of all involved photons is of the order of a MHz and is continuously tunable. This, on the one hand, makes it possible to achieve the necessary temporal measurements resolution with standard electronics, and on the other hand, creates a quantum states source compatible with other candidates for qubit implementation, such as optical transitions in solid-state or vaporous systems. We also discuss the possibility of generating photon pairs with similar temporal modes from two different whispering gallery resonators. |
Document Type: |
Working Paper |
Access URL: |
http://arxiv.org/abs/2412.15760 |
Accession Number: |
edsarx.2412.15760 |
Database: |
arXiv |