Researchers have made a breakthrough in the development of quantum networks with the creation of a single negatively charged lead-vacancy (PbV) center in diamond. This new center emits photons of specific frequencies that are not influenced by the crystal’s vibrational energy, making them ideal carriers of quantum information for large-scale quantum networks.
Published in the journal Physical Review Letters on February 15, 2024, the study reveals that the PbV center emits transform-limited photons with emission into zero-phonon-line (ZPL). This means that the energy associated with the emission of photons is only used to change the electronic configuration of the system and not exchanged with the vibrational lattice modes.
To create the PbV center, lead ions were introduced beneath the diamond surface through ion implantation, followed by an annealing process to repair any damage. The resulting center exhibits a spin 1/2 system with four distinct energy states, with one transition having a transform-limited linewidth of 36 MHz.
This advancement opens up new possibilities for the construction of scalable quantum networks, as the PbV center provides stable and coherent quantum states necessary for quantum information transfer. With the ability to emit transform-limited photons at high temperatures, the PbV center is a promising building block for the future of quantum communication and computation.
