Four-point probe 3-ω method and temperature-dependent resistances. (a) Schematic view of the four-point probe 3-ω method where the out-of-plane thermal conductivity can be measured. (b) The temperature-dependent resistances of three Fe3O4 thin films (100, 300, 400 nm in thickness) at temperature ranges of 20 to 300 K.
Park et al. Nanoscale Research Letters 2014 9:96 doi:10.1186/1556-276X-9-96