An international team of researchers has started to unravel the mysteries of entangled photons, demonstrating a new nanoscale technique that uses semiconductor quantum dots to bend photons to the wavelengths used by today’s popular C-band standards.
The researchers used quantum dots created from an indium arsenide and gallium arsenide platform, producing pure single photons and entangled photons. Unlike parametric down-conversion techniques, quantum dots allow for photons to be emitted only one at a time and on demand, crucial properties for quantum computing. Most entangled photons originating from quantum dots operate near 900 nanometers, closer to wavelengths we can see with the naked eye. “The chance to find a quantum dot that is able to emit polarization-entangled photons with high fidelity is quite high for our specific study,” Olbrich said. Researchers hope that one day, entangled photons will impact cryptography and secure satellite communications.
More information: “Polarization-entangled photons from an InGaAs-based quantum dot emitting in the telecom C-band,” Applied Physics Letters.