Coherent population trapping and strong electromagnetically induced transparency resonances on the D1 line of potassium
Coherent population trapping and strong electromagnetically induced transparency resonances on the D1 line of potassium
复制标题
钾 D1 线上的相干群体捕获和强电磁感应透明共振
DOI：
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发表时间：
2009
期刊：
影响因子：
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通讯作者：
T. Karaulanov
中科院分区：
文献类型：
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作者：
S. Gozzini;S. Cartaleva;A. Lucchesini;C. Marinelli;L. Marmugi;D. Slavov;T. Karaulanov
本文报道了在三能级Λ方案中首次在热钾蒸气中观察到相干布居俘获现象。我们证明，与其他碱的类似方法相比，K具有调制频率低、共振对比度大(高达40%)的优势。我们还报道了在所谓的Hanle组态中K的电磁感应透明(EIT)共振的第一个证据。我们测试了不同类型的电池，发现含K蒸气的抗弛豫涂层和缓冲电池的共振对比度和幅度都有很大的增强：在线宽约为13 mg的情况下，共振对比度达到90%(对于涂层细胞)和65%(对于缓冲细胞)，而在类似条件下，用Ar气体缓冲的Cs蒸气的EIT共振对比度约为1%。这种相关的改善是由于超精细能级多普勒轮廓的重叠而减少了K中的光泵浦，而这在Rb和Cs蒸气的情况下不会发生。因此，K可以被认为在CPT和EIT的进一步应用中非常有前途，特别是对于光抽运损耗是主要限制因素的那些应用，例如光减速和磁测量。
In this paper we report the first experimental observation of coherent population trapping (CPT) in thermal potassium vapor in a three levels Λ scheme. We demonstrate that K presents the advantage of a reduced modulation frequency with a large resonance contrast (up to 40%), in comparison to similar approaches with other alkalis. We report also the first evidence of electromagnetically induced transparency (EIT) resonances in K in the so called Hanle configuration. We tested different kinds of cells, demonstrating strong enhancement of the resonance contrast and amplitude for antirelaxation coated and buffered cells containing K vapor: resonance contrast up to 90% (for coated cells) and 65% (for buffered cells) is achieved with a linewidth of about 13 mG, while under similar conditions, the EIT resonance contrast in Cs vapor buffered by Ar gas is about 1%. Such relevant improvement is due to the reduced optical pumping in K, because of the overlapping of the hyperfine levels Doppler profiles, which does not occur in the case of Rb and Cs vapor. For this reason, K can be considered very promising for further CPT and EIT applications, especially for those where optical pumping losses represent a major limiting factor, such as light slowing and magnetometry.