Evidence for an incommensurate magnetic resonance in La(2-x)Sr(x)CuO(4)

TL;DR

This study investigates how an external magnetic field affects incommensurate magnetic fluctuations in La(1.82)Sr(0.18)CuO(4), revealing field-induced broadening and intensity shifts that relate to the magnetic resonance phenomena in cuprates.

Contribution

It provides new insights into the magnetic response of La(2-x)Sr(x)CuO(4) under magnetic fields, highlighting incommensurate resonance behavior similar to other cuprates.

Findings

Magnetic field broadens incommensurate peaks at 9 meV.

Field causes scattered intensity to shift into the spin gap.

Response at 9 meV resembles the magnetic resonance in other cuprates.

Abstract

We study the effect of a magnetic field (applied along the c-axis) on the low-energy, incommensurate magnetic fluctuations in superconducting La(1.82)Sr(0.18)CuO(4). The incommensurate peaks at 9 meV, which in zero-field were previously shown to sharpen in q on cooling below T_c [T. E. Mason et al., Phys. Rev. Lett. 77, 1604 (1996)], are found to broaden in q when a field of 10 T is applied. The applied field also causes scattered intensity to shift into the spin gap. We point out that the response at 9 meV, though occurring at incommensurate wave vectors, is comparable to the commensurate magnetic resonance observed at higher energies in other cuprate superconductors.