title: Magnetic dispersion of the diagonal incommensurate phase in lightly doped La2-xSrxCuO4.
abstract: We present inelastic neutron scattering experiments on a single-domain crystal of lightly doped La1.96Sr0.04CuO4. We find that the magnetic excitation spectrum in this insulating phase with a diagonal incommensurate spin modulation is remarkably similar to that in the superconducting regime, where the spin modulation is bond parallel. In particular, we find that the dispersion slope at low energy is essentially independent of doping and temperature over a significant range. The energy at which the excitations cross the commensurate antiferromagnetic wave vector increases roughly linearly with doping through the underdoped regime.
authors.affiliation: Quantum Beam Science Directorate, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Matsuda
authors.forename: M
authors.initials: M
authors.lastname: Fujita
authors.forename: S
authors.initials: S
authors.lastname: Wakimoto
authors.forename: J A
authors.initials: JA
authors.lastname: Fernandez-Baca
authors.forename: J M
authors.initials: JM
authors.lastname: Tranquada
authors.forename: K
authors.initials: K
authors.lastname: Yamada