Unconventional transport behavior in the Quaternary Heusler compounds CoFeTiSn and CoFeVGa
arXiv:1810.04865 · doi:10.1016/j.jmmm.2019.01.100
Abstract
We report here the electrical transport and magnetic properties of the newly synthesized quaternary Heusler compound CoFeTiSn and CoFeVGa. We observe a striking change in the electronic transport properties of CoFeTiSn as the system undergoes the paramagnetic to ferromagnetic transition. While the sample shows an activated semiconducting behaviour in the paramagnetic phase, it turns abruptly to a metallic phase with the onset of ferromagnetic transition. We have compared the system with other Hesuler compounds showing similar anomaly in transport, and it appears that CoFeTiSn has much similarities with the FeVAl compound having pseudogap in the paramagnetic phase. In sharp contrast, CoFeVGa shows a predominantly semiconducting behaviour down to 90 K, below which it shows a window of metallic region. Both the compositions show negative Seebeck coefficient varying linearly with temperature. The value of the Seebeck coefficient of CoFeTiSn is comparable to that of many Heusler alloys identified as potential thermoelectric materials.
References in corpus (11)
- Slater-Pauling Behavior of the Half-Ferromagnetic Full-Heusler Alloys
- Inverse magnetocaloric effect in ferromagnetic Ni-Mn-Sn alloys
- Realization of spin gapless semiconductors: the Heusler compound Mn2CoAl
- Spin gapless semiconducting behavior in equiatomic quaternary CoFeMnSi Heusler alloy
- Electronic Structure, Local Moments and Transport in Fe_2VAl
- A new spin gapless semiconductor: quaternary Heusler CoFeCrGa alloy
- High spin polarization in CoFeMnGe quaternary Heusler alloy
- Electronic structure, magnetism and antisite disorder in CoFeCrGe and CoMnCrAl quaternary Heusler alloys
- Competing magnetic and spin gap-less semiconducting behaviour in fully compensated ferrimagnet CrVTiAl: Theory and Experiment
- Ab-initio calculation of the effective on-site Coulomb interaction parameters for half-metallic magnets
- Unusual transport properties of ferromagnetic Heusler alloy CoTiSn