  The quasi-quantized Hall effect (QQHE) is the three-dimensional (3D)
counterpart of the integer quantum Hall effect(QHE),exhibited only by
two-dimensional (2D) electron systems. It has recently been observed in layered
materials, consisting of stacks of weakly coupled 2D platelets. Yet, it is
predicted that the quasi-quantized 3D version of the 2D QHE occurs in a much
broader class of bulk materials, regardless of the underlying crystal
structure. Here, we report the observation of quasi-quantized plateau-like
features in the Hall conductivity of the n-type bulk semiconductor InAs. InAs
takes form of a cubic crystal without any low-dimensional substructure. The
onset of the plateau-like feature in the Hall conductivity scales with
$\sqrt{2/3}k_{F}^{z}/\pi$ in units of the conductance quantum and is
accompanied by a Shubnikov-de Haas minimum in the longitudinal resistivity,
consistent with the predictions for 3D QQHE for parabolic electron band
structures. Our results suggest that the 3D QQHE may be a generic effect
directly observable in materials with small Fermi surfaces, placed in
sufficiently strong magnetic fields.
