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Register a new userGiant frictional drag in strongly interacting bilayers near filling factor one
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We study the frictional drag in high mobility, strongly interacting GaAs bilayer hole systems in the vicinity of the filling factor $ u=1$ quantum Hall state (QHS), at the same fillings where the bilayer resistivity displays a reentrant insulating phase. Our measurements reveal a very large longitudinal drag resistivity ($rho^{D}_{xx}$) in this regime, exceeding 15 k$Omega/Box$ at filling factor $ u=1.15$. $rho^{D}_{xx}$ shows a weak temperature dependence and appears to saturate at a finite, large value at the lowest temperatures. Our observations are consistent with theoretical models positing a phase separation, e.g. puddles of $ u=1$ QHS embedded in a different state, when the system makes a transition from the coherent $ u=1$ QHS to the weakly coupled $ u=2$ QHS.
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