  Coulomb interactions famously drive three dimensional quadratic band crossing
semimetals into a non-Fermi liquid phase of matter. In a previous work, Phys.
Rev. B 95, 205106 (2017), the effect of disorder on this non-Fermi liquid phase
was investigated, assuming that the bandstructure was isotropic, assuming that
the conduction and valence bands had the same band mass, and assuming that the
disorder preserved exact time-reversal symmetry and statistical isotropy. It
was shown that the non-Fermi liquid fixed point is unstable to disorder, and
that a runaway flow to strong disorder occurs. In this work, we extend that
analysis by relaxing the assumption of time-reversal symmetry and allowing the
electron and hole masses to differ (but continuing to assume isotropy of the
low energy bandstructure). We first incorporate time-reversal symmetry breaking
disorder, and demonstrate that there do not appear any new fixed points.
Moreover, while the system continues to flow to strong disorder,
time-reversal-symmetry-breaking disorder grows asymptotically more slowly than
time-reversal-symmetry-preserving disorder, which we therefore expect should
dominate the strong-coupling phase. We then allow for unequal electron and hole
masses. We show that whereas asymmetry in the two masses is irrelevant in the
clean system, it is relevant in the presence of disorder, such that the
'effective masses' of the conduction and valence bands should become sharply
distinct in the low-energy limit. We calculate the RG flow equations for the
disordered interacting system with unequal band masses, and demonstrate that
the problem exhibits a runaway flow to strong disorder. Along the runaway flow,
time-reversal-symmetry-preserving disorder grows asymptotically more rapidly
than both time-reversal-symmetry-breaking disorder and the Coulomb interaction.
