Cavity-induced ATS effect on a superconducting Xmon qubit<xref rid="cpb_27_8_084202fn1" ref-type="fn">*</xref><fn id="cpb_27_8_084202fn1"><label>*</label><p>Project supported by the Science Funds from the Ministry of Science and Technology of China (Grant Nos. 2014CB921401, 2017YFA0304300, 2014CB921202, and 2016YFA0300601), the National Natural Science Foundation of China (Grant No. 11674376), and the Strategic Priority Research Program of the Chinese Academy of Sciences (Grant No. XDB07010300).</p></fn>

Cavity-induced ATS effect on a superconducting Xmon qubit**

Project supported by the Science Funds from the Ministry of Science and Technology of China (Grant Nos. 2014CB921401, 2017YFA0304300, 2014CB921202, and 2016YFA0300601), the National Natural Science Foundation of China (Grant No. 11674376), and the Strategic Priority Research Program of the Chinese Academy of Sciences (Grant No. XDB07010300).

Guo Xueyi^{1, 2}, Deng Hui¹, Ding Jianghao³, Li Hekang^{1, 2}, Song Pengtao^{1, 2}, Wang Zhan^{1, 2}, Su Luhong^{1, 2}, Liu Yanjun¹, Xiang Zhongcheng¹, Li Jie¹, Jin Yirong¹, Liu Yuxi^{3, 4}, Zheng Dongning^{1, 2, †}

(color online) (a) 2D energy spectrum of the Xmon qubit. The Xmon’s as a function of DC bias is shown in this 2D S₂₁ spectrum, and the inset is the avoidcross of the energy spectrum of the Xmon and resonator around . (b) Two-tone energy spectrum of the Xmon. The Xmon is biased at the maximum frequency point, a continuous microwave pump is applied at to the transmission line, and a weak frequency-sweeping probe is applied to detect the scattering spectrum of two upper levels of the qubit. As the pump power increases and the population of state |e〉 increases, the scattering signal of two upper levels |e〉 ↔ |f〉 can be detected.