  We report measurements on in-plane resistivity, thermopower, and
magnetization as a function of temperature and magnetic fields on single
crystalline Sr4Ru3O10 grown by the floating zone method. As the temperature was
lowered to below around 30 K, the in-plane and c-axis resistivities and the
thermopower were found to exhibit a step feature accompanied by hysteresis
behavior when the in-plane field was swept up and down from below 10 kOe to
above 20 kOe. The sharp increase in the thermopower with increasing in-plane
magnetic field at low temperatures has not been observed previously in layered
transition metal oxides. Comparing with magnetization data, we propose that the
step feature marks the transition between the two different electronic states
in Sr4Ru3O10. We propose that the alignment of domains by the in-plane magnetic
field is responsible to the emergence of the new electronic states in high
applied in-plane magnetic field.
