Zero field magnetoresistance peaks in open quantum dots: Weak localization or a fundamental property?

Performing numerical simulations of open quantum dots, we reproduce the zero field resistance peaks seen experimentally, a phenomenon previously attributed to weak localization. Our results show however that these peaks can have a different origin, involving conductance resonances that reflect the underlying spectrum. Even with ensemble averaging, we find that the shape of the resistance peak can be more of a probe of these resonances than of the dynamics of the dot.