Experimental demonstration of single-spin Stirling engine cycles with enhanced efficiencyRemoveP.-D. Li, G.-Y. Ding, J.-Q. Zhang, Q. Yuan, S.-Q. Dai, T.-H. Cui, F. Zhou, L. Chen, Q. Zhong, H. Jing, Ş. K. Özdemir, and M. FengPhys. Rev. A 111, L010203 (2025)