▎ 摘 要
In this Rapid Communication we experimentally probe the nonequilibrium breakdown of the quantum Hall state in monolayer graphene by injecting a high current density (similar to 1 A/m). The measured critical currents for dissipationless transport in the vicinity of integer filling factors show a dependence on filling factor. The breakdown can be understood in terms of inter Landau level (LL) scattering resulting from mixing of wave functions of different LLs. To further study the effect of transverse electric field, we measured the transverse resistance between the nu=2 to nu=6 plateau transition for different bias currents and observed an invariant point.