Fig. 5: Field and angle dependence of the excess boundary conductance.

a Color plot of \(\frac{{\sigma }_{\#1}-{\sigma }_{\#2}}{{\sigma }_{\#1}+{\sigma }_{\#2}}\) at T = 1.55 K. Measurements were simultaneously performed for both samples in a fixed magnetic field at intervals of 0.1 T between 0 and 14 T. Values of \(\frac{{\sigma }_{\#1}-{\sigma }_{\#2}}{{\sigma }_{\#1}+{\sigma }_{\#2}}\) were calculated at each pair of angle and field values and put into a matrix of 721 × 141 dimensions. A commercial software (Origin from OriginLab Corp.) was used to generate the color contour map. Red and blue stripes represent the excess and the deficit of conductivity. b Angle dependence of \(\frac{{\sigma }_{\#1}-{\sigma }_{\#2}}{{\sigma }_{\#1}+{\sigma }_{\#2}}\) at B = 0.2 T and at B = 10 T. The relative deficit and excess conductivity caused by field-boundary alignment does not change significantly in spite of three orders of magnitude change in the amplitude of bulk magnetoconductance. The angle dependence also remains roughly identical for B = 0.2 T and B = 10 T. Insets in panel b show \(\cos (q\theta )\) fits to the data over a narrow angular window (see text).