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arXiv · 2105.14910

Robust population inversion in three-level systems by composite pulses

Cheng Zhang·Yang Liu·Zhi-Cheng Shi·Jie Song·Yan Xia·Shi-Biao Zheng
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Abstract

In this work, we exploit the idea of composite pulses to achieve robust population inversion in a three-level quantum system. The scheme is based on the modulation of the coupling strength, while the other physical parameters remain unchanged. The composite pulses sequence is designed by vanishing high-order error terms, and can compensate the systematic errors to any desired order. In particular, this scheme keeps a good performance under the disturbance of waveform deformations. This trait ensures that population inversion can be nearly obtained even when the pulse sequence has a short jump delay. As an example, we employ the designed composite pulse sequence to prepare the W state in a robust manner in the superconducting circuits. The numerical results show that the fidelity can still maintain a high level in a decoherence environment.

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Cheng Zhang, Yang Liu, Zhi-Cheng Shi, Jie Song, Yan Xia, Shi-Biao Zheng. 2021-05-31. Robust population inversion in three-level systems by composite pulses. https://doi.org/10.1103/physreva.105.042414

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