N.M. Hong

Superconductivity and magnetism in quaternary borocarbides

Abstract We present a status report of the new rare earth transition metal borocarbides and discuss in particular the magnetic properties, results of heat capacity measurements in connection with pressure experiments together with band structure calculations and properties of the superconducting state.

Specific heat of RCo3B2 (R = Y, Sm, Gd, Dy, Lu)

Abstract We present specific heat measurements of the title compounds and discuss the results in connection with their magnetic properties.

Magnetic properties of the Ce2Co7B3 compound

Abstract Ce 2 Co 7 B 3 orders ferromagnetically below 250 K. AC-susceptibility and low dc-field measurements reveal the strong domain wall pinning indicating a large magnetocrystalline anisotropy. At higher fields a metamagnetic transition from a low to a high magnetization state occurs in a wide temperature regime concomitant with a large hysteresis below 150 K.

Magnetic anisotropy of Rn+1Co3n+5B2n (R=Y, La; n=1, 2, 3)

Abstract Magnetization curves have been measured at T = 4.2 K for field-aligned samples of compounds LaCo 4 B and Y n + 1 Co 3 n + 5 B 2 n with n = 1, 2 and 3, in a pulsed high magnetic field up to 35 T. Magnetocrystalline anisotropy constants K 1 have been estimated and discussed for the compounds mentioned above.

Anomalous properties of CeCo4B

Abstract CeCo 4 B is found to undergo an isostructural transition which is strongly dependent on the pressure. A huge magnetic anisotropy exists in a wide temperature regime extending even above Curie temperature.

Specific heat of RNi2B2C(R = Y, Er) and YNi4B

Abstract Comparative heat capacity measurements of YNi 4 B and YNi 2 B 2 C show that the incorporation of carbon in the latter causes a significant lattice stiffening. From the magnetic and specific heat data of ErNi 2 B 2 C we deduce that superconductivity and antiferromagnetism of the Er sublattice coexists below T N .

Weak ferromagnetism in Cr1−xFexAs compound system

Magnetic measurements reveal that the compounds Cr1−xFexAs with 0.1 < x < 0.9 are weak itinerant electron ferromagnets although CrAs and FeAs compounds have a similar double spiral spin ordering.

Magnetic properties of the Ce(Co1−xFex)4B compounds

Abstract The influence of the substitution of Fe for Co on the magnetic properties of the CeCo4B compound is studied. Upon substitution the Curie temperature increases with the rate of 12 K/Fe-at% whereas the magnetic anisotropy of the compound rapidly decreases.