Quantum Hall liquid-to-insulator transition in ${\mathrm{In}}_{1\mathrm{-}\mathrm{x}}$${\mathrm{Ga}}_{\mathrm{x}}$As/InPt heterostructures

We report a temperature- and current-scaling study of the quantum Hall liquid-to-insulator transition in an ${\mathrm{In}}_{1\mathrm{-}\mathrm{x}}$${\mathrm{Ga}}_{\mathrm{x}}$As/InP heterostructure. When the magnetic field is at the critical field ${\mathrm{B}}_{\mathrm{c}}$, ${\mathrm{\rho }}_{\mathrm{xx}}$=0.86h/${\mathrm{e}}^2$. Furthermore, the transport near ${\mathrm{B}}_{\mathrm{c}}$ scales as |B- ${\mathrm{B}}_{\mathrm{c}}$|${\mathrm{T}}^{\mathrm{-}\mathrm{\kappa }}$ with κ=0.45±0.05, and as |B- ${\mathrm{B}}_{\mathrm{c}}$|${\mathrm{I}}^{\mathrm{-}\mathrm{b}}$ with b=0.23±0.05. The latter can be due to phonon emission in a dirty piezoelectric medium, or can be the consequence of critical behavior near ${\mathrm{B}}_{\mathrm{c}}$, within which z=1.0±0.1 and ν=2.1±0.3 are obtained from our data.