  Cyclotron motion of charge carriers in metals and semiconductors leads to
Landau quantization and magneto-oscillatory behavior in their properties.
Cryogenic temperatures are usually required to observe these oscillations. We
show that graphene superlattices support a different type of quantum
oscillations that do not rely on Landau quantization. The oscillations are
extremely robust and persist well above room temperature in magnetic fields of
only a few T. We attribute this phenomenon to repetitive changes in the
electronic structure of superlattices such that charge carriers experience
effectively no magnetic field at simple fractions of the flux quantum per
superlattice unit cell. Our work points at unexplored physics in Hofstadter
butterfly systems at high temperatures.
