标题： 单层基于铋的铜氧化物在赝间隙终点附近的光致反射率弛豫动力学 显示英文标题

标题： Critical photoinduced reflectivity relaxation dynamics in single-layer Bi-based cuprates near the pseudogap end point

摘要： 对重掺杂单层铜氧化物（Bi,Pb）$_{2}$Sr$_{2}$CuO$_{6+\delta}$（Pb-Bi2201）在赝隙相和超导相的端点之间的光诱导瞬态反射率动力学进行了全面研究，使用了光学超快时间分辨泵浦-探测光谱技术。 在接近赝隙端点的Pb-Bi2201中，高于$T_{{\rm c}}$的瞬态反射率动力学类似于最佳掺杂的La-Bi2201中观察到的赝隙响应。 然而，在低温下，弛豫时间表现出幂律发散，$\tau\sim10\hbar/k_{\mathrm{B}}T$，表明在赝隙端点掺杂处存在量子临界行为。 在Pb-Bi2201略微超过赝隙掺杂端点处也观察到了弛豫时间的类似幂律增加，尽管不那么明显。 显示英文摘要

摘要： A comprehensive study of photoinduced transient reflectivity dynamics in heavily overdoped single-layer cuprate (Bi,Pb)$_{2}$Sr$_{2}$CuO$_{6+\delta}$ (Pb-Bi2201), across the end points of the pseudogap and superconducting phases, has been conducted using optical ultrafast time-resolved pump-probe spectroscopy. In the Pb-Bi2201 just before reaching the pseudogap end point, the transient reflectivity dynamics above $T_{{\rm c}}$ resemble the pseudogap response observed in optimally doped La-Bi2201. At low temperatures, however, the relaxation time exhibits a power-law divergence, $\tau\sim10\hbar/k_{\mathrm{B}}T$, signaling quantum critical behavior at the pseudogap end point doping. A similar power-law increase in relaxation time is also observed in Pb-Bi2201 just beyond the pseudogap doping end point, though it is less pronounced.