Project 10: Rare-earth-ion doped quantum memories for quantum repeaters

Host Institute: University of Geneva

Project Supervisor: Dr  Mikael Afzelius

ESR: Antonio Ortu

Starting date: January 2017

Duration: 3 years

Project Description

Quantum repeaters enable the distribution of quantum states over long distances, and are at the core of future quantum networks, or the “quantum internet”. They also enable long-distance QKD and remote quantum sensing. This disruptive technology is extremely challenging, particularly due to the need for high performance quantum memories, which are needed for storage or quantum processing in the network. In this project we will work on a solid-state quantum memory system based on rare-earth-ion doped crystals (REIC). These systems have advanced to a position where they are among the main candidates for quantum memories. We will aim at creating quantum correlations between a single spin excitation in an REIC and a telecommunications photon, which is the basic resource for quantum repeaters, using Raman-type excitations. To this end we will develop a scheme for generating correlations first between a visible photon and a stored spin excitation. We will then work on techniques for extending the storage time to the millisecond regime using NMR techniques. Finally we will investigate methods for converting the visible photon to the telecom domain (a quantum interface), such as sum-frequency-generation, and characterize the quantum correlations using photon counting techniques.

Project Outcomes

To be updated.