@article{oai:nagoya.repo.nii.ac.jp:00010162,
author = {Mune, Yoriko and Ohta, Hiromichi and Koumoto, Kunihito and Mizoguchi, Teruyasu and Ikuhara, Yuichi},
journal = {APPLIED PHYSICS LETTERS},
month = {Nov},
note = {We report two-dimensional Seebeck coefficients (|S|_2D) of [(SrTiO_3)x/(SrTi_0.8Nb_0.2O_3)y]_20 (x=1–60, y=1–20) superlattices, which were grown on the (100) face of insulating LaAlO_3 substrates to clarify the origin of the giant |S|_2D values of the SrTiO_3 superlattices [H. Ohta et al., Nat. Mater. 6, 129 (2007)]. The |S|_2D values of the [(SrTiO_3)_17/(SrTi_0.8Nb_0.2O_3)y]_20 superlattices increased proportionally to y^{−0.5} and reached 320µVK^{−1} (y=1), which is approximately five times larger than that of the SrTi_0.8Nb_0.2O_3 bulk (|S|_3D=61µVK^{−1}). The slope of the log|S|_2D-log y plots was −0.5, proving that the density of states in the ground state for SrTiO_3 increases inversely proportionally to y. The critical barrier thickness for quantum electron confinement was also clarified to be 6.25nm (16 unit cells of SrTiO_3).},
pages = {192105--192105},
title = {Enhanced Seebeck coefficient of quantum-confined electrons in SrTiO_3/SrTi_0.8Nb_0.2O_3 superlattices},
volume = {91},
year = {2007}
}