On the Theory of a New Maximum Observed in dc Transport in Modulated Quantum Hall Systems Near ν=1/2
We propose a theory for the new maximum recently observed by Willett et al [1] in the longitudinal magnetoresistance of a weakly modulated two-dimensional electron gas (2DEG) near filling factor ν=1/2 for the current driven along the modulation lines. The maximum is superimposed upon a new resonance structure. This occurs due to the geometric resonance of composite fermion cyclotron orbits with the period of modulation of the effective magnetic field. We propose here a semiquantitative theory of the dc magnetotransport in a modulated 2DEG near one half filling. Our analysis is based on the Boltzmann transport equation and it enables us to obtain this maximum which was neither observed nor predicted previously.
cond-mat.mes-hall↗