Staggered magnetization inLa2−xSr

Electronic phase separation in lightly dopedLa2−xSrxCuMatsuda1, Fujita2, Yamada3 et al. 2002Phys. Rev. B173191592View full textAdd to dashboardCite

“…24,29 It has been found that a static internal field, determined from both 139 La NQR and µSR, develops below T N with a further increase at T ∼30 K, and the latter temperature does not depend on the hole concentration. The two characteristic temperatures are consistent with those determined from our neutron scattering studies.…”

Theory of spin fluctuations in striped phases of doped antiferromagnetic cuprates

“…We note, in particular, that the zero point magnetizations are extrapolated values. As is explained in [6], there is a change of behavior around T = 30K for all values of doping. The authors have interpreted this as some sort of freezing of the holes, which may be binding to the donor impurities, establishing static charge density waves within the stripes, or some other change in behavior.…”

“…The experimental values are those of Ref. [6]. We note, in particular, that the zero point magnetizations are extrapolated values.…”

“…Yet the growing theoretical literature [2] supporting the tendency toward microscopic phase separation of holes in these strongly correlated quasi-two-dimensional materials, as well as the experimental observation [3,4] of stripe phenomena in many related systems, raises the strong possibility that the doped antiferromagnetic cuprates will also be characterized by such stripes. Moreover, there is indirect evidence of linear, or striped, features in the magnetic structure of these materials, including the finite size scaling properties [5] of the Néel temperature and uniform magnetic susceptibility, and the successful interpretation [6,7] of muon spin resonance (µSR) and nuclear quadrupole resonance (NQR) experiments within models that presume a striped structure.Those latter theories are nominally based on a static periodic array of stripes, which separate antiferromagnetic slabs, or ladders, at most weakly coupled to one another across the stripes. Since such regular arrays are not observed in the neutron scattering experiments, we want to consider a broader class of striped structures.…”

“…Instead, as in [11], we use the asymptotic long distance behavior of the equal time spin-spin correlation function: σ(x, y)σ(0, 0) → (M s /M 0 ) 2 as x, y → ∞, where M 0 represents perfect Néel spin alignment. To do this we evaluate (6) at the point where the scaled length r s is equal to the Josephson correlation length ξ J =hc/ρ s , which separates long from short wavelength scales. On the one hand, this is large enough for the correlation function to have reached its desired asymptotic behavior, but it is still short enough that the (exponential) decay due to the long wavelength fluctuations at T = 0 + where (6) holds has not yet become effective.…”