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D Lederman

Publications and source records attributed to D Lederman.

At least 19 recordsLinked to original sources
PubMed2003

Exchange-induced anisotropies at ferromagnetic-antiferromagnetic interfaces above and below the Néel temperature.

The exchange bias and magnetic anisotropies in a Co layer on a single-crystalline FeF2 film have been determined between 30 and 300 K. By postulating that the coupling between the ferromagnet and the antiferromagnet persists above the Néel temperature (T(N)) we develop a model that quantitatively describes the exchange bias and the anisotropies over the whole temperature range, both above and below T(N). Using only the measured low temperature exchange bias and a distribution of blocking temperatures we explain (i) the temperature dependence of the bias, (ii) the magnitude of the anisotropies, (iii) the opposite sign of the first and second order anisotropies, (iv) the observed 1/T and 1/T(3) temperature dependencies of the first and second order uniaxial anisotropies above T(N), and (v) the decrease of the anisotropies below T(N).

Journal Article↗
PubMed2002

Order parameter criticality of the d = 3 random-field Ising antiferromagnet Fe0.85Zn0.15F2.

The critical exponent beta=0.16+/-0.02 for the random-field Ising model order parameter is determined using extinction-free magnetic x-ray scattering for Fe0.85Zn0.15F2 in magnetic fields of 10 and 11 T. The observed value is consistent with other experimental random-field critical exponents, but disagrees sharply with Monte Carlo and exact ground state calculations on finite-sized systems.

Journal Article↗
PubMed1984

Gingival hyperplasia associated with nifedipine therapy. Report of a case.

A case of gingival hyperplasia associated with the administration of nifedipine is reported. Clinically and histologically, the tissue resembled that seen in hyperplasia induced by phenytoin (Dilantin). We believe this to be the first reported case of gingival hyperplasia associated with this drug.

Female↗