Ultrafast transient reflectivity measurements of optimally doped Bi2+xSr2-xCaCu2O8+delta with disorder
Ultrafast transient reflectivity measurements of optimally doped Bi2+xSr2-xCaCu2O8+delta with disorder
复制标题
无序最佳掺杂 Bi2 xSr2-xCaCu2O8 δ 的超快瞬态反射率测量
DOI：
10.1103/physrevb.104.094507
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发表时间：
2021
影响因子：
3.7
通讯作者：
Mihailovic D.
中科院分区：
文献类型：
--
作者：
Toda Y.;Tsuchiya S.;Oda M.;Kurosawa T.;Katsumata S.;Naseska M.;Mertelj T.;Mihailovic D.
从通过时间分辨泵浦探针光谱获得的光致准粒子（QP）动力学的角度研究了高超导体中无序的影响。我们对具有由 Bi-Sr 取代引起的面外无序的最佳掺杂 (OPD)(Bi2212) 进行测量，这种无序存在于标准 Bi2212 中，但通常不受控制。基于受控无序的系统变化，我们识别了超导（SC）和赝能隙（PG）态中QP弛豫和能隙形成的动力学变化。 PG 响应的起始温度随 的增加而增加，比 的轻微降低更为显着。这些特性等效地反映在 SC 和 PG 态的破坏注量中。 Bi-Sr 替代还加速了 SC 和 PG QP 的弛豫时间，这可能是由于无序引起的声子散射概率增加所致。相反，在强激发条件下观察到的 SC 间隙恢复显示出相同的能量密度依赖性，这意味着该无序对相干间隙形成没有显着贡献。
The effect of disorder in high-superconductors is investigated from the viewpoint of photoinduced quasiparticle (QP) dynamics, obtained through time-resolved pump-probe spectroscopy. We perform the measurements on an optimally doped (OPD)(Bi2212) with an out-of-plane disorder induced by Bi-Sr substitution, which is present in standard Bi2212 but is not usually controlled. Based on the systematic change of the disorder with controlled, we identify the changes in the dynamics of QP relaxation and gap formation in superconducting (SC) and pseudogap (PG) states. The onset temperatureof the PG response increases with an increase in, which is more significant than the slight decrease in. These properties are equivalently reflected in the destruction fluences of the SC and PG states. Bi-Sr substitution also accelerates relaxation times for SC and PG QPs, which can be due to the increased phonon scattering probability caused by the disorder. In contrast, the SC gap recovery observed in the strongly excited condition shows an identical fluence dependence for various, implying that the disorder does not significantly contribute to coherent gap formation.