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arXiv · 2110.05281

Stability of Floquet Majorana box qubits

Anne Matthies·Jinhong Park·Erez Berg·Achim Rosch
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Abstract

In one-dimensional topological superconductors driven periodically with the frequency $\omega$, two types of topological edge modes may appear, the well-known Majorana zero mode and a Floquet Majorana mode located at the quasi-energy $\hbar \omega/2$. We investigate two Josephson-coupled topological quantum wires in the presence of Coulomb interactions, forming a so-called Majorana box qubit. An oscillating gate voltage can induce Floquet Majorana modes in both wires. This allows encoding 3 qubits in a sector with fixed electron parity. If such a system is prepared by increasing the amplitude of oscillations adiabatically, it is inherently unstable as interactions resonantly create quasi particles. This can be avoided by using instead a protocol where the oscillation frequency is increased slowly. In this case, one can find a parameter regime where the system remains stable.

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Anne Matthies, Jinhong Park, Erez Berg, Achim Rosch. 2021-10-11. Stability of Floquet Majorana box qubits. https://doi.org/10.1103/physrevlett.128.127702

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