title: Spin pseudogap in Ni-doped SrCuO2.
abstract: The S=1/2 spin chain material SrCuO2 doped with 1% S=1 Ni impurities is studied by inelastic neutron scattering. At low temperatures, the spectrum shows a pseudogap Δ≈8  meV, absent in the parent compound, and not related to any structural phase transition. The pseudogap is shown to be a generic feature of quantum spin chains with dilute defects. A simple model based on this idea quantitatively accounts for the experimental data measured in the temperature range from 2 to 300 K, and allows us to represent the momentum-integrated dynamic structure factor in a universal scaling form.
authors: Neutron Scattering and Magnetism, Laboratory for Solid State Physics, ETH Zürich, Zürich 8093, Switzerland.
authors: G
authors: G
authors: Simutis
authors: S
authors: S
authors: Gvasaliya
authors: M
authors: M
authors: Månsson
authors: A L
authors: AL
authors: Chernyshev
authors: A
authors: A
authors: Mohan
authors: S
authors: S
authors: Singh
authors: C
authors: C
authors: Hess
authors: A T
authors: AT
authors: Savici
authors: A I
authors: AI
authors: Kolesnikov
authors: A
authors: A
authors: Piovano
authors: T
authors: T
authors: Perring
authors: I
authors: I
authors: Zaliznyak
authors: B
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authors: Büchner
authors: A
authors: A
authors: Zheludev