All-electrically reading out and initializing topological qubits with quantum dots

TL;DR

This paper proposes an all-electrical method for reading and initializing topological qubits encoded by Majorana fermions in nanowires, using a quantum dot to achieve direct measurement and control.

Contribution

It introduces a novel all-electrical approach for reading and initializing topological qubits via quantum dots, enabling practical quantum information processing.

Findings

Qubit readout achieved through quantum dot occupation during Majorana fusion

Qubit initialization via gate voltage adjustment on the quantum dot

Both processes are fully electrical, enhancing experimental feasibility

Abstract

We analyze the reading and initialization of a topological qubit encoded by Majorana fermions in one-dimensional semiconducting nanowires, weakly coupled to a single level quantum dot (QD). It is shown that when the Majorana fermions are fused by tuning gate voltage, the topological qubit can be read out directly through the occupation of the QD in an energy window. The initialization of the qubit can also be realized via adjusting the gate voltage on the QD, with the total fermion parity conserved. As a result, both reading and initialization processes can be achieved in an all-electrical way.