  How the two dimensional (2D) quantum Wigner crystal (WC) transforms into the
metallic liquid phase remains to be an outstanding problem in physics. In
theories considering the 2D WC to liquid transition in the clean limit, it was
suggested that a number of intermediate phases might exist. We have studied the
transformation between the metallic fluid phase and the low magnetic field
reentrant insulating phase (RIP) which was interpreted as due to WC formation
[Qiu et al, PRL 108, 106404 (2012)], in a strongly correlated 2D hole system
with large interaction parameter $r_s$ ($\sim~$20-30) and high mobility.
Instead of a sharp transition, we found that increasing density (or lowering
$r_s$) drives the RIP into a state where the incipient RIP coexists with Fermi
liquid. This apparent mixture phase intermediate between Fermi liquid and WC
also exhibits a non-trivial temperature dependent resistivity behavior which
may be qualitatively understood by the reversed melting of WC in the mixture,
in analogy to the Pomeranchuk effect in the solid-liquid mixture of Helium-3.
