Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China.
J Phys Condens Matter. 2013 Jun 26;25(25):256006. doi: 10.1088/0953-8984/25/25/256006. Epub 2013 Jun 6.
The magnetocaloric effect (MCE) associated with the spin transitions of alternating longitudinal conical (ALC)-mixed conical (MC) and MC-ferrimagnetic (FIM) states in a Ba0.3Sr1.7Co2Fe12O22 single crystal has been investigated. For magnetic field directions applied along either the [120] or [001] directions, the crystal is found to exhibit the conventional and inverse MCE near the ALC-MC (T(N1) = 235 K) and MC-FIM (T(N2) = 348 K) states, respectively. The dependence of the magnetic entropy on the magnetic field also exhibits such sign change behaviors in the MCE, which is attributed to the magnetic field induced gradual collapse of heliconical magnetic order.
钡锶钴铁氧体单晶中交替纵向锥形（ALC）-混合锥形（MC）和 MC-亚铁磁（FIM）态自旋转变相关的磁热效应（MCE）已被研究。对于沿[120]或[001]方向施加的磁场方向，该晶体分别在 ALC-MC（T（N1）= 235 K）和 MC-FIM（T（N2）= 348 K）状态附近表现出常规和逆磁热效应。磁熵随磁场的变化也表现出这种磁热效应中的符号变化行为，这归因于磁场诱导的螺旋磁有序的逐渐崩塌。
