@article { doi:10.1126/sciadv.aea6541,
	title = {Critical point{\textendash}based wireless sensors enabling tiny perturbation detection},
	journal = {Science Advances},
	volume = {12},
	number = {21},
	year = {2026},
	pages = {eaea6541},
	abstract = {High quality factor and sensitivity are critical to wireless sensors targeting small perturbation detection. Although introducing parity-time symmetric dynamics promises enhanced performance, the symmetric scheme often yields limited sensing behaviors. In particular, its implementation is hindered by the inherent difficulties in decoupling capacitance- and coupling strength{\textendash}induced responses, the requirements of delicately matching and/or tuning both gain and loss, and the need of strong coupling strength. Here, we report a concept of critical point (CP){\textendash}based wireless sensors that do not rely on balanced gain-loss configurations, delivering ultrahigh quality factor with an extended interrogation distance. Owing to a sharp and deep reflection dip, the CP-based scheme can resolve the change in coupling coefficient down to 1.92\&amp;nbsp;{\texttimes}\&amp;nbsp;10-4 and features frequency-independent responses. Furthermore, the CP-based scheme allows for identification of tiny asymmetric capacitive perturbations as small as 2.5\&amp;nbsp;{\texttimes}\&amp;nbsp;10-5 without requiring active tuning of the other parameters under weak coupling. Critical-point wireless sensors with unbalanced gain and loss enable reliable and sensitive detection under weak coupling.},
	doi = {10.1126/sciadv.aea6541},
	url = {https://www.science.org/doi/abs/10.1126/sciadv.aea6541},
	author = {Chao Ma and Ke Yin and Zhuoyu Zhang and Ruyi Huang and Yuangen Huang and Gan, Lanyue and Liu, Yuxuan and Fan Xia and Xia, Tian and Yufan Chen and Wangchang Li and Peng, Lian-Mao and Tianyu Dong and Hu, Youfan}
}
