Entanglement distillation using the exchange interaction

• DOI: 10.1007/s00340-015-6286-7
• Publication Date: 2016-03-10T09:52:19Z
• Authors: Adrian Auer; René Schwonnek; Christian Schoder; Lars Dammeier; Reinhard F. Werner; Guido Burkard
• Keywords: Quantum Physics; 0103 physical sciences; FOS: Physical sciences; Quantum Physics (quant-ph); 01 natural sciences

8 pages, 5 figures, v2: corrected typo in Eq. (7)<br/>A key ingredient of quantum repeaters is entanglement distillation, i.e., the generation of high-fidelity entangled qubits from a larger set of pairs with lower fidelity. Here, we present entanglement distillation protocols based on qubit couplings that originate from exchange interaction. First, we make use of asymmetric bilateral two-qubit operations generated from anisotropic exchange interaction and show how to distill entanglement using two input pairs. We furthermore consider the case of three input pairs coupled through isotropic exchange. Here, we characterize a set of protocols which are optimizing the tradeoff between the fidelity increase and the probability of a successful run.<br/>