Laser energy tuning of carrier effective mass and thermopower in epitaxial oxide thin films

Abstract

The effect of the laser fluence on high temperature thermoelectric properties of the La doped SrTiO3 (SLTO) thin films epitaxially grown on LaAlO3 〈100〉 substrates by pulsed laser deposition is clarified. It is shown that oxygen vacancies that influence the effective mass of carriers in SLTO films can be tuned by varying the laser energy. The highest power factor of 0.433 W K−1 m−1 has been achieved at 636 K for a film deposited using the highest laser fluence of 7 J cm−2 pulse−1.

A d-Band Electron Correlated Thermoelectric Thermistor Established in Metastable Perovskite Family of Rare-Earth Nickelates

“…Nevertheless, because of the significantly increased electrical conductivity, a higher thermoelectric power factor is observed in the metallic phase of Re NiO 3 compared to their insulating phase, as shown in Figure d. It is worth noticing that the thermoelectric power factor achieved in the metallic phase of Sm 0.75 Eu 0.25 NiO 3 and Sm 0.75 Nd 0.25 NiO 3 exceeds the ones reported for conventional thermoelectric oxides of Ca 3 Co 4 O 9 and approaches to doped SrTiO 3 and BiSeCuO …”

“…(a–c) Temperature dependence of (a) the resistivity, (b) temperature coefficient of resistance (TCR), and (c) thermopower for Re NiO 3 /LAO samples ( Re =Nd, Sm, Eu, Y, Dy, Sm 0.75 Eu 0.25 , and Sm 0.75 Nd 0.25 ). (d) Temperature dependence of the thermoelectric power factor for as-grown Re NiO 3 /LAO samples compared to the conventional thermoelectric oxide materials of Ca 3 Co 4 O 9 , doped SrTiO 3 , and BiSeCuO …”

“…(a) Temperature coefficient of resistance (TCR) and (b) thermopower ( S ) for Re NiO 3 /LAO samples ( Re = Nd, Sm, Eu, Y, Dy, Sm 0.75 Eu 0.25 , and Sm 0.75 Nd 0.25 ) at room temperature and 90 °C. (c) The TCR– S relation at room temperature compared for the Re NiO 3 /LAO samples in this work with conventional thermoelectric compounds, such as N-type Bi 2 Te 3 , Bi 1– x Sb x , PbTe, filled CoSb 3 , Ca 3 Co 4 O 9 , doped SrTiO 3 , − BiSeCuO, and Na x CoO 2 . (d) TCR and S of EuNiO 3 and YNiO 3 below room temperature from −55 to 30 °C.…”

“…The coexistence of large temperature coefficient of resistance (TCR) and high thermoelectric thermopower ( S ) beyond conventional semiconductors was achieved within the insulating phase of DyNiO 3 and YNiO 3 . Furthermore, a comparably high thermoelectric power factor to conventional thermoelectric oxides (i.e., Ca 3 Co 4 O 9 , , doped SrTiO 3 , − and BiSeCuO) was achieved in the metallic phase of Re NiO 3 . Bridging the multiple functionalities coexists in Re NiO 3 sheds a light on new applications, e.g., thermal perturbation sensor combining both active and passive detection modes.…”

Effect of oxygen vacancy distribution on the thermoelectric properties of La-doped SrTiO3 epitaxial thin films

“…In addition, a clean laser window was used for every experiment to eliminate any run-to-run variation in laser fluence at the target due to coating on the laser window. 33 The thermoelectric films were then subjected to two cycles of thermoelectric measurement in Ar/H 2 (denoted by film A) and Ar gas (denoted by B).…”