English

Conditions allowing error correction in driven qubits

Mesoscale and Nanoscale Physics 2019-01-21 v2

Abstract

We consider a qubit that is driven along its logical zz axis, with noise along the zz axis in the driving field Ω\Omega proportional to some function f(Ω)f(\Omega), as well as noise along the logical xx axis. We establish that whether or not errors due to both types of noise can be canceled out, even approximately, depends on the explicit functional form of f(Ω)f(\Omega) by considering a power-law form, f(Ω)Ωkf(\Omega)\propto\Omega^k. In particular, we show that such cancellation is impossible for k=0k=0, 11, or any even integer. However, any other odd integer value of kk besides 11 does permit cancellation; in fact, we show that both types of errors can be corrected with a sequence of four square pulses of equal duration. We provide sets of parameters that correct for errors for various rotations and evaluate the error, measured by the infidelity, for the corrected rotations versus the na\"ive rotations, i.e., the operations that, in the complete absence of noise, would produce the desired rotations (in this case a single pulse of appropriate duration and magnitude). We also consider a train of four trapezoidal pulses, which take into account the fact that there will be, in real experimental systems, a finite rise time, again providing parameters for error-corrected rotations that employ such pulse sequences. Our dynamical decoupling error correction scheme works for any qubit platform as long as the errors are quasistatic.

Keywords

Cite

@article{arxiv.1810.07184,
  title  = {Conditions allowing error correction in driven qubits},
  author = {Robert E. Throckmorton and S. Das Sarma},
  journal= {arXiv preprint arXiv:1810.07184},
  year   = {2019}
}

Comments

9+$\epsilon$ pages, 6 figures, 5 tables. Added discussion of realistic values of noise parameters in the case of a semiconductor-based singlet-triplet spin qubit. Clarified some definitions of terms. Now published in Phys. Rev. B; this is the published version

R2 v1 2026-06-23T04:42:13.129Z