Structural and magnetotransport properties of epitaxial films and Hall bar devices of metallic delafossite PdCoO₂

PdCoO₂ is a delafossite compound that has sparked increasing interest due to its unusual bulk electronic transport characteristics [1]. The growth of metallic delafossite PdCoO₂ in thin film form would enable the implementation of its fascinating properties in various electronic applications including transparent electrodes and correlated transparent conductors [2,3]. Yet, there are only a few reports on thin film growth of PdCoO₂ [4]. In this talk, we will be discussing the structural, microstructural and electronic transport properties of epitaxial PdCoO₂ thin films structured into Hall bar devices. The PdCoO₂ thin films of various thicknesses were grown on Al₂O₃ substrates using the pulsed laser deposition technique, and several Hall bar devices of different widths were patterned side-by-side on the same sample. This allowed us to study the properties of these devices as a function of both the device width and the film thickness. We report on the high crystalline quality as well as the low resistivity of the films with minimal structural defects. In addition, we present the magnetotransport properties of the films and discuss how these characteristics compare with those of pure bulk single crystals.

References

[1] P. J. W. Moll et al., Science 351, 1061 (2016).

[2] T. Harada et al., APL Mater. 6, 046107 (2018)

[3] L. Zhang et al., Nat. Mater. 15, 204 (2016).

[4] T. Harada, Mater. Today Adv. 11, 100146 (2021).