Readout using Resonant Tunneling in Silicon Spin Qubits

TL;DR

This paper proposes a resonant tunneling-based readout method for silicon spin qubits, enabling rapid and multiple measurements within coherence time, potentially improving quantum dot array detection efficiency.

Contribution

It introduces a theoretical approach using resonant tunneling controlled by a transistor for efficient qubit state measurement in silicon spin qubits.

Findings

Over a hundred measurements possible during coherence time

Resonant tunneling exhibits nonlinear characteristics beneficial for measurement

Potential integration with conventional transistors for readout

Abstract

Spin qubit systems are one of the promising candidates for quantum computing. The quantum dot (QD) arrays are intensively investigated by many researchers. Because the energy-difference between the up-spin and down-spin states is very small, the detection of the qubit state is of prime importance in this field. Moreover, many wires are required to control qubit systems. Therefore, the integration of qubits and wires is also an important issue. In this study, the measurement process of QD arrays is theoretically investigated using resonant tunneling, controlled by a conventional transistor. It is shown that the number of possible measurements during coherence time can exceed a hundred under the backaction of the measurements owing to the nonlinear characteristics of resonant tunneling. It is also discussed to read out the measurement results by the conventional transistor.