Bandwidth-limited and noisy pulse sequences for single qubit operations in semiconductor spin qubits

TL;DR

This paper investigates the effects of bandwidth limitations and noise on pulse sequences used for single qubit operations in semiconductor spin qubits, considering realistic control signal transients and disturbances.

Contribution

It introduces a comprehensive model of control pulse imperfections, including filtering and noise, for more accurate simulation of single qubit gate operations in semiconductor spin qubits.

Findings

Bandwidth limitations affect qubit rotation fidelity.

Noise impacts the robustness of control pulses.

Realistic pulse modeling improves gate performance predictions.

Abstract

Spin qubits are very valuable and scalable candidates in the area of quantum computation and simulation applications. In the last decades, they have been deeply investigated from a theoretical point of view and realized on the scale of few devices in the laboratories. In semiconductors, spin qubits can be built confining the spin of electrons in electrostatically defined quantum dots. Through this approach it is possible to create different implementations: single electron spin qubit, singlet-triplet spin qubit, or a three electrons architecture, e. g. the hybrid qubit. For each qubit type, we study the single qubit rotations along the principal axis of Bloch sphere including the mandatory non-idealities of the control signals that realize the gate operations. The realistic transient of the control signal pulses are obtained by adopting an appropriate low-pass filter function. In addition the effect of disturbances on the input signals is taken into account by using a Gaussian noise model.