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arXiv · 2506.19572

DRAG-Compatible Leakage Suppression in Landau--Zener Control via Isoprobability Twins

Ivo S. Mihov·Nikolay V. Vitanov
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Abstract

Analytically solvable models -- particularly the Landau-Majorana-St\"uckelberg-Zener (LMSZ) and Allen-Eberly-Hioe (AEH) models -- underpin many quantum-gate implementations and population-transfer protocols. However, their canonical pulse shapes are incompatible with modern leakage-suppression techniques and some systems. Most notably, the constant Rabi envelope of the LMSZ pulse prevents many leakage-suppression approaches, which require smoothness. We address both limitations by developing the concept of isoprobability twin models: distinct pairs of Rabi frequency $\Omega(t)$ and detuning $\Delta(t)$ that yield identical post-pulse transition probabilities based on the Delos-Thorson transformation. In this work, we formalise the method by experimentally demonstrating the equivalence of multiple LMSZ and AEH twin models on IBM's ibm_kyiv processor. Finally, we show a staggering leakage reduction by more than 3 orders of magnitude using a custom DRAG implementation of a cosine LMSZ isoprobability model.

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Ivo S. Mihov, Nikolay V. Vitanov. 2025-06-24. DRAG-Compatible Leakage Suppression in Landau--Zener Control via Isoprobability Twins. https://arxiv.org/abs/2506.19572

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