Precise measurements of polarizabilities of cesium nS Rydberg states in an ultra-cold atomic ensemble
Jingxu Bai, Suying Bai, Xiaoxuan Han, Yuechun Jiao, Jianming Zhao, Suotang Jia
Abstract
Abstract We present precise measurements of polarizabilities of cesium n S 1/2 ( n = 65–75) Rydberg states by Stark spectroscopies. In experiment, Rydberg atoms are excited via a two-photon scheme of a standard magneto-optical trap and detected by the field ionization technique. The Stark shift is measured by analysing the spectroscopy under an external electric field. The polarizability, α , is acquired by fitting the experimental data of Stark shifts with <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline" overflow="scroll"> <mml:mi mathvariant="normal">Δ</mml:mi> <mml:mi>W</mml:mi> <mml:mo>=</mml:mo> <mml:mo>−</mml:mo> <mml:mfrac> <mml:mrow> <mml:mn>1</mml:mn> </mml:mrow> <mml:mrow> <mml:mn>2</mml:mn> </mml:mrow> </mml:mfrac> <mml:mi>α</mml:mi> <mml:msup> <mml:mrow> <mml:mi>E</mml:mi> </mml:mrow> <mml:mrow> <mml:mn>2</mml:mn> </mml:mrow> </mml:msup> </mml:math> . The theoretical model is applied to numerically simulate the Stark map and corresponding level shifts, related deviation between the experimental measurements and calculations are less than 2%. The scaling law of polarizabilities, <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline" overflow="scroll"> <mml:mi>A</mml:mi> <mml:mo>⋅</mml:mo> <mml:msup> <mml:mrow> <mml:mrow> <mml:mo stretchy="false">(</mml:mo> <mml:mrow> <mml:msup> <mml:mrow> <mml:mi>n</mml:mi> </mml:mrow> <mml:mrow> <mml:mo>*</mml:mo> </mml:mrow> </mml:msup> </mml:mrow> <mml:mo stretchy="false">)</mml:mo> </mml:mrow> </mml:mrow> <mml:mrow> <mml:mn>7</mml:mn> </mml:mrow> </mml:msup> <mml:mo>+</mml:mo> <mml:mi>B</mml:mi> <mml:mo>⋅</mml:mo> <mml:msup> <mml:mrow> <mml:mrow> <mml:mo stretchy="false">(</mml:mo> <mml:mrow> <mml:msup> <mml:mrow> <mml:mi>n</mml:mi> </mml:mrow> <mml:mrow> <mml:mo>*</mml:mo> </mml:mrow> </mml:msup> </mml:mrow> <mml:mo stretchy="false">)</mml:mo> </mml:mrow> </mml:mrow> <mml:mrow> <mml:mn>6</mml:mn> </mml:mrow> </mml:msup> </mml:math> ( n * is effective principal quantum number), is attained, that shows a good agreement with the measurements.