A population transfer from the upper level of the clock transition in thulium atoms to the ground level is demonstrated by using radiation with a wavelength of 402 nm. The method for detecting the clock transition excitation that is not affected by technical fluctuations of the number of atoms in an optical lattice is investigated. The hyperfine splitting of the |4f 12 ( 3 F 2 )5d 5/2 6s 2 ; J = 7/2 ##IMG## [https://ej.iop.org/icons/Entities/rang.gif] {rang} level in the thulium atom is measured to be 1480(9) MHz. The suggested method for population transfer can be applied to both the hyperfine components of the clock transition intended for compensating Zeeman effect in a thulium optical clock.

中文翻译：

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通过使用再吸收激光辐射检测th原子中的时钟跃迁

通过使用波长为402 nm的辐射，可以证明从th原子的时钟跃迁的上位向地位迁移。研究了不受光学晶格中原子数的技术波动影响的时钟转变激发的检测方法。| 4f 12（3 F 2）5d 5/2 6s 2的超精细分裂；J = 7/2 ## IMG ## [https://ej.iop.org/icons/Entities/rang.gif] rang原子中的{rang}能级被测量为1480（9）MHz。可以将建议的人口转移方法应用于时钟过渡的两个超精细部分，以补偿a光学时钟中的塞曼效应。