We consider the leakage suppression problem of a three-level system in which the first two levels are the qubit system and the third, weakly-coupled to the second, is the leakage state. We show that phase- and amplitude-controlled two (three) pulses are sufficient for arbitrary qubit controls from the ground (an arbitrary) initial state, with leakage suppressed up to the first order of perturbation without additional pulse-area cost. A proof-of-principle experiment was performed with shaped femtosecond optical pulses and atomic rubidium showing a good agreement with the theory.
@article{arxiv.1801.04060,
title = {Leakage suppression by ultrafast pulse shaping},
author = {Hanlae Jo and Yunheung Song and Jaewook Ahn},
journal= {arXiv preprint arXiv:1801.04060},
year = {2019}
}