We report muSR data from pseudo-cubic and layered copper fluorides, KCuF3, K2CuF4, and its substitutions K1.9Sr0.1CuF4, K2CuF3.9O0.1, K2C1.8Zn0.2F4. In KCuF3, the extinction of the F-Mu-F fraction and its progressive replacement by a magnetic fraction between 40 and 35 K demonstrate a first-order magnetic transition at T-N, probably driven by orbital degrees of freedom. The layered compounds exhibit on the contrary conventional second-order transitions at T-c = 6.25 K, independent of electron or hole doping up to at least x = 0.1. However, 20% substitution of Cu with non-magnetic Zn completely suppresses long-range magnetic order above 1.3 K.
Magnetic transition in orbitally ordered KCuF3, K2CuF4 and heterovalently substituted compounds / Mazzoli, Claudio; Allodi, Giuseppe; Guidi, Germano; DE RENZI, Roberto; P., Ghigna; C., Baines. - In: PHYSICA. B, CONDENSED MATTER. - ISSN 0921-4526. - 326:(2003), pp. 427-430. [10.1016/S0921-4526(02)01656-3]
Magnetic transition in orbitally ordered KCuF3, K2CuF4 and heterovalently substituted compounds
MAZZOLI, Claudio;ALLODI, GIUSEPPE;GUIDI, Germano;DE RENZI, Roberto;
2003-01-01
Abstract
We report muSR data from pseudo-cubic and layered copper fluorides, KCuF3, K2CuF4, and its substitutions K1.9Sr0.1CuF4, K2CuF3.9O0.1, K2C1.8Zn0.2F4. In KCuF3, the extinction of the F-Mu-F fraction and its progressive replacement by a magnetic fraction between 40 and 35 K demonstrate a first-order magnetic transition at T-N, probably driven by orbital degrees of freedom. The layered compounds exhibit on the contrary conventional second-order transitions at T-c = 6.25 K, independent of electron or hole doping up to at least x = 0.1. However, 20% substitution of Cu with non-magnetic Zn completely suppresses long-range magnetic order above 1.3 K.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
