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arXiv · 1307.1159

Tunability of microwave transitions as a signature of coherent parity mixing effects in the Majorana-Transmon qubit

Eran Ginossar·Eytan Grosfeld
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Abstract

Coupling Majorana fermion excitations to coherent external fields is an important stage towards their manipulation and detection. We analyse the charge and transmon regimes of a topological nano-wire embedded within a Cooper-Pair-Box, where the superconducting phase difference is coupled to the zero energy parity states that arise from Majorana quasi-particles. We show that at special gate bias points, the photon-qubit coupling can be switched off via quantum interference, and in other points it is exponentially dependent on the control parameter $E_J/E_C$. As well as a probe for topological-superconductor excitations, we propose that this type of device could be used to realise a tunable high coherence four-level system in the superconducting circuits architecture.

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Eran Ginossar, Eytan Grosfeld. 2013-12-07. Tunability of microwave transitions as a signature of coherent parity mixing effects in the Majorana-Transmon qubit. https://doi.org/10.1038/ncomms5772

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