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arXiv · 1504.03055

Manipulating the Majorana Qubit with the Landau-Zener-Stückelberg Interference

Wen-Chao Huang·Qi-Feng Liang·Dao-Xin Yao·Zhi Wang
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Abstract

Constructing a universal operation scheme for Majorana qubits remains a central issue for the topological quantum computation. We study the Landau-Zener-Stückelberg interference in a Majorana qubit and show that this interference can be used to achieve controllable operations. The Majorana qubit consists of an rf SQUID with a topological nanowire Josephson junction which hosts Majorana bound states. In the SQUID, a magnetic flux pulse can drive the quantum evolution of the Majorana qubit. The qubit experiences two Landau-Zener transitions when the amplitude of the pulse is tuned around the superconducting flux quanta $2e/\hbar$. The Landau-Zener-Stückelberg interference between the two transitions rotates the Majorana qubit, with the angle controlled by the time scale of the pulse. This rotation operation implements a high-speed single-qubit gate on the Majorana qubit, which is a necessary ingredient for the topological quantum computation.

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Wen-Chao Huang, Qi-Feng Liang, Dao-Xin Yao, Zhi Wang. 2015-04-13. Manipulating the Majorana Qubit with the Landau-Zener-Stückelberg Interference. https://doi.org/10.1103/physreva.92.012308

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