A quantum light-emitting diode for the standard telecom window around 1,550 nm

Abstract

Single photons and entangled photon pairs are a key resource of many quantum secure communication and quantum computation protocols, and non-Poissonian sources emitting in the low-loss wavelength region around 1,550 nm are essential for the development of fibre-based quantum network infrastructure. However, reaching this wavelength window has been challenging for semiconductor-based quantum light sources. Here we show that quantum dot devices based on indium phosphide are capable of electrically injected single photon emission in this wavelength region. Using the biexciton cascade mechanism, they also produce entangled photons with a fidelity of 87 ± 4%, sufficient for the application of one-way error correction protocols. The material system further allows for entangled photon generation up to an operating temperature of 93 K. Our quantum photon source can be directly integrated with existing long distance quantum communication and cryptography systems, and provides a promising material platform for developing future quantum network hardware.

Entanglement Swapping with Semiconductor-Generated Photons Violates Bell’s Inequality

“…Integrating QDs into micro-cavities can increase their brightness and photon indistinguishability [39,40]. Another key ingredient towards a scalable quantum photonic network is electrically triggered photon emis-sion [41,42]. Decoherence due to coupling to the solidstate environment can be controlled by electric fields in QD integrated diode structures [43].…”

High‐Purity Triggered Single‐Photon Emission from Symmetric Single InAs/InP Quantum Dots around the Telecom C‐Band Window

“…For instance, combining the InP matrix with the double‐cap technique in metalorganic chemical vapor deposition (MOCVD) showed high suppression of multiphoton events under non‐resonant and quasi‐resonant excitation. MOCVD‐grown structures allowed also for realization of single‐photon emission under electrical carrier injection . However, all of them lead to strongly anisotropic structures with FSS well above 20 µeV therefore limiting their applicability.…”

Generation of Non‐Classical Light Using Semiconductor Quantum Dots

“…In the year 2000, it was proposed that QDs can be used as sources of entangled photon pairs which was for the first time experimentally demonstrated in 2006 and over recent years their potential as high‐quality sources has been established . An important milestone for the generation of entangled photon pairs was the development of two‐photon excitation of either in a resonant two‐photon process or via a detuned phonon‐mediated process which allows for an on‐demand generation with high efficiency .…”