Reflective terahertz time-domain spectroscopy measurement on the stripe-ordered superconductor La$_{1.84-y}$Nd$_y$Sr$_{0.16}$CuO$_4$

摘要

We measured reflectivity on static stripe-orderedLa$_{1.84-y}$Nd$_y$Sr$_{0.16}$CuO$_4$ (LNSCO) $y$\,=\,0.1, 0.2, 0.3, and 0.4 bymeans of reflective terahertz time-domain spectroscopy (THz-TDS) with electricfield polarized along c-axis, in which one can obtain lower frequencyinformation than the conventional Fourier transform type spectrometer.Recently, two-dimensional superconducting (2DSC) property\cite{tajima,schafgans,li}, intra-layer perfect conductivity not accompaniedwith inter-layer superconducting behavior, was reported on LNSCO($x$\,=0.15\,,\,$y$\,$\geq$\,0.2). We observed the existence of Josephsonplasma edge, which suggests that 2DSC is not realized in these compounds.