  We report a study of quantum oscillations (QO) in the magnetic torque of the
nodal-line Dirac semimetal ZrSiS in the magnetic fields up to 35 T and the
temperature range from 40 K down to 2 K, enabling high resolution mapping of
the Fermi surface (FS) topology in the $k_z=\pi$ (Z-R-A) plane of the first
Brillouin zone (FBZ). It is found that the oscillatory part of the measured
magnetic torque signal consists of low frequency (LF) contributions
(frequencies up to 1000 T) and high frequency (HF) contributions (several
clusters of frequencies from 7-22 kT). Increased resolution and angle-resolved
measurements allow us to show that the high oscillation frequencies originate
from magnetic breakdown (MB) orbits involving clusters of individual $\alpha$
hole and $\beta$ electron pockets from the diamond shaped FS in the Z-R-A
plane. Analyzing the HF oscillations we have unequivocally shown that the QO
frequency from the dog-bone shaped Fermi pocket ($\beta$ pocket) amounts
$\beta=591(15)$ T. Our findings suggest that most of the frequencies in the LF
part of QO can also be explained by MB orbits when intraband tunneling in the
dog-bone shaped $\beta$ electron pocket is taken into account. Our results give
a new understanding of the novel properties of the FS of the nodal-line Dirac
semimetal ZrSiS and sister compounds.
