The hidden competing phase revealed by first-principles calculations of phonon instability in the nearly optimally doped cuprate La${}_{1.875}$Sr${}_{0.125}$CuO${}_4$

Chi-Cheng Lee, Ji-Yao Chiu, Yukiko Yamada-Takamura +1

The representative cuprate, La${}_{2-x}$M${}_x$CuO${}_4$, with M = Sr and $x=1/8$ is studied via first-principles calculations in the high-temperature tetragonal (HTT), low-temperature…