超冷铯分子纯长程态转动常数的精密测量

Precise measurements of rotational constants of the pure long range state of ultracold cesium molecules

利用调制的俘获损耗光谱技术实验测量了超冷铯分子纯长程0g态的高分辨光谱.采用双光缔合光谱技术构建了精确的频率差参考信号,对转动能级的共振频率间隔进行了精确的标定,获得了转动能级频率间隔与转动量子数的关系.通过将实验数据拟合到非刚性转动模型,获得了超冷铯分子纯长程0g态不同振动态的转动常数.实验结果表明转动常数随振动量子数的增加而线性减小,线性递减率为0.41 MHz±0.01 MHz.

The high resolution spectrum of ultracold Cs2 pure long range 0^-g state is experimentally measured using modulated trap loss spectroscopic technology. Based on Double photoassociation spectroscopic technique, precise frequency difference reference signals are constructed to accurately calibrate the resonant frequency intervals of the ro-vibrational levels, thus obtaining the relationship between the frequency interval of rotational level and the rotational quantum number. The experimental data are fitted by the non-rigid rotational model, and the molecular rotational constants corresponding to different vibrational levels in the ultracold Cs2 pure long range 0^-g state are acquired. The experimental results demonstrate a linear decrease of the rotational constant with the increase of vibrational quantum number, and the linear decreasing rate is？0.41 MHz ± 0.01 MHz.