Heralded Quantum Gates with Integrated Error Detection

QuICS Seminar

Johannes Borregaard (Harvard)
Thursday, July 9, 2015 - 2:00pm
CSS 3100A

Individual atoms in optical cavities can provide an efficient interface between light and matter, something essential to quantum communication. Through the cavity field, quantum gates, such as the CNOT gate, can be realized between atoms trapped in the same cavity, which can be used in e.g. a quantum repeater to swap entanglement to large distances. Nonetheless, dissipation caused by cavity decay and spontaneous emission increases the experimental difficulty of realizing high quality gates in such a setup.

In this talk, I will discuss how error detection can be employed to convert the dissipation errors, which would be present in a deterministic gate, into a non-unity success probability. Once successful, the resulting gate exhibit much higher fidelity than a similar deterministic gate. Furthermore, I will discuss how such a heralded gate can be directly incorporated in a quantum repeater to circumvent the demanding task of intermediate entanglement purification and thus greatly increase the distribution rate.