Bonn 2025 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

QI: Fachverband Quanteninformation

QI 35: Quantum Information: Concepts and Methods II

QI 35.7: Vortrag

Donnerstag, 13. März 2025, 16:00–16:15, HS IV

A Color Center based Scheme for the Storage and Retrieval of a Quantum Token — •Yannick Strocka, Mohamed Belhassen, Gregor Pieplow, and Tim Schröder — Institut für Physik, Humboldt-Universität zu Berlin, Newtonstr. 15, 12489 Berlin, Deutschland

Quantum tokens are of growing interest in the era of secure communication in large scale quantum networks. Compared to classical tokens they are unforgeable because of the no-cloning principle. A quantum token can be a multi-qubit state comprised of single or entangled qubits. Such multi-qubit states can be efficiently produced using single photon sources, such as quantum dots or color centers in diamond. For a practical implementation of a quantum token scheme a token has to be issued and a user has to have the ability to save and redeem the token. In this work we focus on the user, possessing a register of quantum memories based on group-IV color centers in diamond. Such defects are promising due to their long spin coherence times and reduced sensitivity to electric field noise when integrated into nanostructures. In our proposed scheme, saving the token using the color centers' spin requires the use of a spin rotation and spin dependent reflection of the incoming photons. For performing such a rotation quickly we investigate optical spin gates using a Raman scheme. We analyze the impact of imperfections of the photon source, spin rotations and measurement on the resulting fidelity of the quantum token. We also study the overall performance of the spin based quantum memory register for receiving and sending quantum tokens.

Keywords: quantum tokens; quantum control; color centers; quantum communication; quantum registers