Speaker
Description
Nd$_{0.4}$La$_{1.6-x}$Sr$_x$CuO$_4$ (Nd-LSCO) is a prototypical high T$_C$ cuprate superconductor. At a hole-doping of x = 0.125 = 1/8, this compound is notable for displaying both static spin stripe order and charge stripe order, as well as a heavily suppressed superconducting T$_C$ ~ 3 K. Previous high-field transport [1] and thermopower measurements [2] have shown that the electronic properties of Nd-LSCO are highly sensitive to applied hydrostatic pressure, with a suppression of the pseudogap phase and a weakening of charge stripe order reported by P ~ 2 GPa. In contrast, the pressure dependence of the magnetic properties of Nd-LSCO has remained largely unexplored.
In this talk, we will present neutron diffraction measurements on high quality single crystal samples of Nd-LSCO (x=0.125), performed using the VERITAS and SNAP beamlines at Oak Ridge National Laboratory. These measurements allow us to characterize the pressure dependence of the structural and magnetic phase diagrams up to P = 1.7 GPa. We observe a remarkable enhancement of spin stripe order above 1 GPa, with magnetic scattering persisting up to room temperature at maximum pressure. Applied pressure also stabilizes the tetragonal crystal structure of NdLSCO, with a significant decrease in the HTT-to-LTO transition temperature (from ~450 K to ~300 K at 1.7 GPa) and a corresponding increase in the LTO-to-LTT transition (from ~68 K to ~80 K under the same conditions).
[1] N. Doiron-Leyraud et al, Nat. Commun. 8, 2044 (2017).
[2] A. Gourgout et al, Phys. Rev. Res. 3,023066 (2021).
| Keyword-1 | Superconductivity |
|---|---|
| Keyword-2 | Neutron Scattering |
| Keyword-3 | High Pressure |
