Ultimate photovoltage in perovskite oxide heterostructures with critical film thickness

Abstract

Articles you may be interested inOptimization on photoelectric detection based on stacked La0.9Sr0.1MnO3−δ/LaAlO3−δ multijunctions

Significant enhancement of photovoltage in artificially designed perovskite oxide structures

“…As we reported earlier, 20 an ultimate value of photovoltage in the heterostructures with the film thickness is consistent with the calculated thickness of the depletion layer in LSMO films for heterostructures of LSMO/SNTO. Therefore, the photovoltage of a heterojunction is proposed to be related to its thickness of the depletion layer.…”

“…We also expected that it may be twice larger than the photovoltage of single LSMO/SNTO junction due to much thinner layer of the SNTO (10 nm) in the upper junction than that (the substrate SNTO 0.5 mm) of in the lower junction, as we already know that thinner film can even increase the photovoltage to one order larger, also, due to the reduction of the recombination of photogenerated carriers during their drifting process. 20 However, a 20 times larger photovoltage than that in the single junction still surprised us, and the mechanism behind this significant enhancement remains an open question, and we expect that some further studies both experimentally and theoretically can shine some light on it. As shown in Fig.…”

“…[17][18][19] Previously, we have reported an ultimate value of photovoltage in the heterostructures with a film thickness consistent with the calculated thickness of the depletion layer in LSMO films for heterostructures of LSMO/ SrNb 0.008 Ti 0.992 O 3 and LSMO/Si. 7,20 In this work, we designed two kinds of multilayer structures, and obtained as much as 20 times larger photovoltage than that in the single heterostructures. The mechanism behind this dramatically enhancement is discussed.…”

Device Performance of the Mott InsulatorLaVO3as a Photovoltaic Material

“…However, as we discussed in the section above, the charge transport properties of most TMOs at room temperature are far inferior compared to those of crystalline semiconductors like Si and GaAs. As a result, the optimized thicknesses of a TMO layer in these photovoltaic diodes should be comparable to the depletion layer thickness, which is often only several tens of nanometers due to the high dielectric constant and the associated strong screening effect [61]. If the TMO layer is too thick, there will be no driving force to separate the photocarriers, and no photocurrent will be able to reach the electrodes.…”

Crucial role played by interface and oxygen content in magnetic properties of ultrathin manganite films

“…14 In particular, the presence of a so-called "dead layer" when the thickness of manganite films drops down to a certain value leads to the decrease of spin polarization and the depression of magnetic and transport properties. 15 More recently, the ultimate photo-voltage in manganite-based heterostructures with a critical film thickness was discovered, 16 which indicates that more intriguing properties may yet not be exposed, especially in the ultrathin films of perovskite oxides. In this paper, we present a systematic investigation on the structural and magnetic properties of the La 0.9 Sr 0.1 MnO 3 (LSMO) films with the thicknesses varying from several hundred to 6 u.c.…”