Crossover effect of inter-granular transport and quantum correction in Co-doping La2/3Ca1/3MnO3 manganites

► Electrical and magnetic properties of a series of Co doped manganites are studied. ► The low temperature resistivity minimum is observed for all the samples. ► There is an abnormal effect in low temperature resistivity minimum due to Co doping. ► The Crossover effect of inter-granular transport and quantum correction is firstly investigated.