We have grown Bi2Sr2Co2Oy thin films on LaAlO3 (100) and fused silica substrates by pulsed laser deposition. The films on LaAlO3 are c-axis oriented and partially in-plane aligned with multiple domains while the films on fused silica are preferred c-axis oriented without in-plane alignment. The Seebeck coefficient and resistivity of films on both substrates are comparable to those of single crystals. A large nonlinear resistivity related to the suppression of the spin density wave by external electric field was also observed. An oxide p-n heterojunction was formed by depositing Bi2Sr2Co2Oy film on Nb-doped SrTiO3 single crystal, which showed a rectifying behavior. These thin films and heterostructures may be used for novel thermoelectric applications.
Citation: Applied Physics Letters
Pub Type: Journals
Bi2Sr2Co2Oy films on LaAlO3 (100), texture, thermoelectric properties, PLD, oxide p-n junction