arXiv subjects

H. R. Ott

Publications and source records attributed to H. R. Ott.

56 records · Page 4Linked to original sources

arXiv2000

LiVGe2O6, an anomalous quasi 1D, $S = 1$ system, as revealed by NMR

We report the results of $^{7}$Li nuclear magnetic resonance (NMR) studies of LiVGe$_{2}$O$_{6}$, a quasi one--dimensional spin $S = 1$ model system, at low temperatures. Our data, including NMR spectra and the temperature dependence of the spin-lattice relaxation rate $T_{1}^{-1}$, indicate a first order phase transition to occur at $T_{c}\simeq 23$ K. The NMR response of LiVGe$_{2}$O$_{6}$ below $T_{c}$ suggests that the ordered phase is antiferromagnetic and has unusual features. Possible reasons for this unexpected behavior are discussed.

cond-mat.str-el↗

arXiv1994

Nonlinear Susceptibility: A Direct Test of the Quadrupolar Kondo Effect in UBe(13)

We present the nonlinear susceptibility as a direct test of the quadrupolar Kondo scenario for heavy fermion behavior, and apply it to the case of cubic crystal-field symmetry. Within a single-ion model we compute the nonlinear susceptibility resulting from low-lying Γ_3 (5f^2 and Kramers (5f^3) doublets. We find that nonlinear susceptibility measurements on single-crystal UBe_{13} are inconsistent with a quadrupolar 5f^2 ground-state of the uranium ion; the experimental data indicate that the low-lying magnetic excitations of UBe_{13} are predominantly dipolar in character.

cond-mat↗