Magnetoresistance and dHvA oscillations in YbB₆. (a) Illustration of the electronic structure of YbB₆ in the 3D and 2D projected Brillouin zones. The bottom shows the FS obtained in our ARPES experiment. (b) The field dependence magnetic torque τ (upper panel) and its first derivative dτ/dH (lower panel) of YbB₆. Oscillating patterns are observed in magnetic field higher than 8 T. The inset is the sketch of the experimental setup. The sample stage is rotated to tilt magnetic field H in the crystalline a–c plane. The magnetic field is applied to the sample with a tilt angle f relative to the crystalline c axis. (c) The oscillatory magnetic torques plotted as a function of 1/µ₀H, clearly revealing the quantum oscillation pattern. (d) The main oscillation peak and its harmonic are observed in the FFT transformations of the derivative dτ/dH. The inset shows the corresponding FS pockets of each main oscillation peak, with the extracted area contour of the surface states at Γ¯ and X¯ labeled by the dotted green and blue curves, respectively. (e) The oscillatory torque signals measured at selected temperatures in magnetic field up to 35 T and tilt angle ϕ ∼ 10°. (f) The temperature dependence of the normalized FFT peak amplitudes for both pockets α and β. The effective mass is determined by fitting the temperature dependence to the thermal damping factor R_T of the LK formula.