English

Implementation of single-qubit gates via parametric modulation in the Majorana transmon

Mesoscale and Nanoscale Physics 2022-05-30 v1

Abstract

We present a voltage gate-based method for controlling the Majorana transmon, using a sinusoidal modulation of the induced offset charge ngn_g. Working in the transmon regime and in the instantaneous eigenstates basis, we find the time evolution under this protocol that realises tunable XX-ZZ rotations. We optimise the parameters of the system for different single-qubit gates in both the laboratory frame and the qubit rotating frame, obtaining qubit control errors 1F1-\mathcal{F} smaller than 2×104\sim2\times 10^{-4}. In addition to this, we conduct an analysis of the effects of the charge noise, assuming wide-band 1/f1/f additive noise in ngn_g, both for the free and the driven evolutions. For the free evolution, the relaxation and dephasing rates are calculated perturbatively, obtaining long dephasing times of the order of milliseconds at the system's sweet-spots. For the driven case, the average fidelity for the XX-gate is obtained via a numerical simulation, demonstrating remarkable resilience.

Keywords

Cite

@article{arxiv.2205.14033,
  title  = {Implementation of single-qubit gates via parametric modulation in the Majorana transmon},
  author = {Elena Lupo and Eytan Grosfeld and Eran Ginossar},
  journal= {arXiv preprint arXiv:2205.14033},
  year   = {2022}
}