TY - JOUR
T1 - Reversal of the lattice structure in SrCoOx epitaxial thin films studied by real-time optical spectroscopy and first-principles calculations
AU - Choi, Woo Seok
AU - Jeen, Hyoungjeen
AU - Lee, Jun Hee
AU - Seo, S. S.Ambrose
AU - Cooper, Valentino R.
AU - Rabe, Karin M.
AU - Lee, Ho Nyung
PY - 2013/8/27
Y1 - 2013/8/27
N2 - Using real-time spectroscopic ellipsometry, we directly observed a reversible lattice and electronic structure evolution in SrCoOx (x=2.5-3) epitaxial thin films. Drastically different electronic ground states, which are extremely susceptible to the oxygen content x, are found in the two topotactic phases: i.e., the brownmillerite SrCoO2.5 and the perovskite SrCoO3. First-principles calculations confirmed substantial differences in the electronic structure, including a metal-insulator transition, which originate from the modification in the Co valence states and crystallographic structures. More interestingly, the two phases can be reversibly controlled by changing the ambient pressure at greatly reduced temperatures. Our finding provides an important pathway to understanding the novel oxygen-content-dependent phase transition uniquely found in multivalent transition metal oxides.
AB - Using real-time spectroscopic ellipsometry, we directly observed a reversible lattice and electronic structure evolution in SrCoOx (x=2.5-3) epitaxial thin films. Drastically different electronic ground states, which are extremely susceptible to the oxygen content x, are found in the two topotactic phases: i.e., the brownmillerite SrCoO2.5 and the perovskite SrCoO3. First-principles calculations confirmed substantial differences in the electronic structure, including a metal-insulator transition, which originate from the modification in the Co valence states and crystallographic structures. More interestingly, the two phases can be reversibly controlled by changing the ambient pressure at greatly reduced temperatures. Our finding provides an important pathway to understanding the novel oxygen-content-dependent phase transition uniquely found in multivalent transition metal oxides.
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U2 - 10.1103/PhysRevLett.111.097401
DO - 10.1103/PhysRevLett.111.097401
M3 - Article
AN - SCOPUS:84884269441
SN - 0031-9007
VL - 111
JO - Physical Review Letters
JF - Physical Review Letters
IS - 9
M1 - 097401
ER -