Tuning the electronic effective mass in double-doped SrTiO3
Ravichandran, J., W. Siemons, M.L. Scullin, S. Mukerjee, M. Huijben, J.E. Moore, A. Majumdar, Ramamoorthy Ramesh
We elucidate the relationship between effective mass and carrier concentration in an oxide semiconductor controlled by a double-doping mechanism. In this model oxide system, Sr1-xLaxTiO 3-δ, we can tune the effective mass ranging from 6 to 20m e as a function of filling (carrier concentration) and the scattering mechanism, which are dependent on the chosen lanthanum- and oxygen-vacancy concentrations. The effective mass values were calculated from the Boltzmann transport equation using the measured transport properties of thin films of Sr1-xLaxTiO3-δ. We show that the effective mass decreases with carrier concentration in this large-band-gap, low-mobility oxide, and this behavior is contrary to the traditional high-mobility, small-effective-mass semiconductors. © 2011 The American Physical Society.
Physical Review B - Condensed Matter and Materials Physics
Year of Publication