Europhys. Lett.
Volume 73, Number 2, January 2006
Page(s) 260 - 266
Section Condensed matter: electronic structure, electrical, magnetic, and optical properties
Published online 02 December 2005
Europhys. Lett., 73 (2), pp. 260-266 (2006)
DOI: 10.1209/epl/i2005-10373-x

Pressure effect on the pseudogap in the optimally doped high-temperature superconductor $\chem{La_{1.81}Sr_{0.15}Ho_{0.04}Cu^{16}O_4}$

P. S. Häfliger1, A. Podlesnyak1, K. Conder2 and A. Furrer1

1  Laboratory for Neutron Scattering, ETH Zurich & PSI Villigen CH-5232 Villigen PSI, Switzerland
2  Laboratory for Developments and Methods, Condensed Matter Research with Neutrons and Muons - CH-5232 Villigen PSI, Switzerland

received 2 June 2005; accepted in final form 4 October 2005
published online 2 December 2005

The effect of hydrostatic pressure on the relaxation rate of crystal-field excitations in the optimally doped high-Tc superconductor $\chem{La_{1.81}Sr_{0.15}Ho_{0.04}Cu^{16}O_4}$ ( $T_c=32.5\un{K}$) has been investigated by means of inelastic neutron scattering. The temperature T* where the pseudogap opens is found to shift downwards from $T^*=(61.0\pm1.3)\un{K}$ (p=0) to $T^*=(55.8\pm1.5)\un{K}$ ( $p=0.8\un{GPa}$) and to $T^*=(54.1\pm1.5)\un{K}$ ( $p=1.2 \un{GPa}$), i.e., $\upd
T^*/\upd p=(-5.9\pm1.6)\un{K/GPa}$.

74.62.Fj - Pressure effects.
76.30.Kg - Rare-earth ions and impurities.
78.70.Nx - Neutron inelastic scattering.

© EDP Sciences 2006