Absolute strong-field ionization probabilities of ultracold rubidium atoms
Absolute strong-field ionization probabilities of ultracold rubidium atoms
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DOI：
10.1038/s42005-018-0032-5
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发表时间：
2017-11
影响因子：
5.5
通讯作者：
Philipp Wessels;B. Ruff;Tobias Kroker;A. Kazansky;N. Kabachnik;K. Sengstock;M. Drescher;J. Simonet
中科院分区：
文献类型：
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作者：
Philipp Wessels;B. Ruff;Tobias Kroker;A. Kazansky;N. Kabachnik;K. Sengstock;M. Drescher;J. Simonet
理解强场电离需要在实验数据和理论模型之间进行定量比较，这是出了名的难以实现的。光捕获的超冷原子可以通过成像暴露在超短激光脉冲场后的原子密度来提取绝对非线性电离概率。我们报道了在1 × 1011 - 4 × 1013W cm−2的强度范围内对铷的这种精确测量。实验数据与ab-initio理论完全一致，该理论基于求解时间相关的Schrödinger方程，不含任何自由参数。在Keldysh参数接近于统一的条件下，研究了87rb原子在两种不同波长下的非共振和共振过程的强场响应。
Understanding strong-field ionization requires a quantitative comparison between experimental data and theoretical models which is notoriously difficult to achieve. Optically trapped ultracold atoms allow to extract absolute nonlinear ionization probabilities by imaging the atomic density after exposure to the field of an ultrashort laser pulse. We report on such precise measurements for rubidium in the intensity range of 1 × 1011– 4 × 1013W cm−2. The experimental data are in perfect agreement with ab-initio theory, based on solving the time-dependent Schrödinger equation without any free parameters. We investigate the strong-field response of87Rb atoms at two different wavelengths representing non-resonant and resonant processes in the demanding regime where the Keldysh parameter is close to unity.