Fig. 2: Azimuthal (φ) angular dependence of the magnetoresistance in Nd0.8Sr0.2NiO2.
From: Rotational symmetry breaking in superconducting nickelate Nd0.8Sr0.2NiO2 films
a Schematic of the Corbino-disk device for azimuthal (φ) angular dependent magnetoresistance measurements. Here, φ represents the angle between the magnetic field and the a/b-axis of the Nd0.8Sr0.2NiO2. b, c Azimuthal angle dependence of the magnetoresistance R(φ) at different temperatures under B = 8 T in the polar plot (b) and rectangular plot (c). d, e Azimuthal angle dependence of the magnetoresistance R(φ) at T = 2 K under B = 16 T in the polar plot (d) and rectangular plot (e). Here, the logarithmic scale is used on the resistance-axis to specifically demonstrate the C2 symmetric feature. The blue solid lines are fits with the trigonometric function: R = Ravg + ΔRC4 × sin(4φ) + ΔRC2 × sin(2φ), where Ravg is the averaged magnetoresistance and ΔRC4 and ΔRC2 are the C4 and C2 components, respectively. The light blue area in (d) is a guide to the eye, representing the C2 anisotropy. f, g Four-fold components ΔRC4 (f) and two-fold components ΔRC2 (g) versus the ratio between the averaged magnetoresistance and the normal state resistance (Ravg/RN) under different magnetic fields. Here, the values of the C2 and C4 components are extracted by the trigonometric function fitting.
