Thin films of perovskite manganese oxide Lao.66Ca0.29K0.05MnO3(LCKMO) on Au/ITO(ITO=indium tin oxide) substrates were prepared by off-axis radio frequency magnetron sputtering and characterized by X-ray diffrac- t...Thin films of perovskite manganese oxide Lao.66Ca0.29K0.05MnO3(LCKMO) on Au/ITO(ITO=indium tin oxide) substrates were prepared by off-axis radio frequency magnetron sputtering and characterized by X-ray diffrac- tion(XRD), high-resolution transmission electron microscopy(HRTEM), and conductive atomic force microscopy (C-AFM) at room temperature. The thin films with thickness ranged from 100 nm to 300 nm basically show cubic structures with a=0.3886 nm, the same as that of the raw material used, but the structures are highly modulated. C-AFM results revealed that the atomic scale p-n junction feature of the thin films was the same as that of the single crystals. The preparation of the thin films thus further confirms the possibility of their application extending from micrometer-sized single crystals to macroscopic thin film.展开更多
We have successfully fabricated the colossal magnetoresistive (CMR) p-n junctions of perovskite oxide La0.9Sr0.1MnO3/SrNb0.01Ti0.99O3 (LSMO/SNTO) with laser molecular beam epitaxy. The I-V characteristics of the LSMO/...We have successfully fabricated the colossal magnetoresistive (CMR) p-n junctions of perovskite oxide La0.9Sr0.1MnO3/SrNb0.01Ti0.99O3 (LSMO/SNTO) with laser molecular beam epitaxy. The I-V characteristics of the LSMO/SNTO p-n junctions as a function of applied magnetic field (05 T) were studied between 100 and 300 K. We found that the p-n junction exhibited the CMR behavior. The CMR ratio rR/R0 (rR = RH - R0) is positive in magnetic fields below 0.13 T and at high temperature, while it displays a negative CMR near 100 K and in magnetic fields over 0.13 T. The CMR ratio values are 8% at 0.1 T and 13% at 5 T and 300 K, 40% at 0.1 T and 150 K, 10% at 0.13 T and 60% at 5 T and 100 K. The CMR behavior of the p-n junction is different from those of the LaMnO3 compound family.展开更多
Nanosecond (ns) photoelectric effects have been observed in all-oxide p-n junctions of La0.9Sr0.1MnO3/SrNb0.01Ti0.99O3 for the first time. The rise time was about 23 ns and the full width at half maximum was about 125...Nanosecond (ns) photoelectric effects have been observed in all-oxide p-n junctions of La0.9Sr0.1MnO3/SrNb0.01Ti0.99O3 for the first time. The rise time was about 23 ns and the full width at half maximum was about 125 ns for the open-circuit photovoltaic pulse when the La0.9Sr0.1MnO3 thin film in the p-n junction was irradiated by a laser of ~20 ns pulse duration and 308 nm wavelength. The photovoltaic sensitivity was 80 mV/mJ for a 308 nm laser pulse.展开更多
基金Supported by the National Natural Science Foundation of China(No.90922034)
文摘Thin films of perovskite manganese oxide Lao.66Ca0.29K0.05MnO3(LCKMO) on Au/ITO(ITO=indium tin oxide) substrates were prepared by off-axis radio frequency magnetron sputtering and characterized by X-ray diffrac- tion(XRD), high-resolution transmission electron microscopy(HRTEM), and conductive atomic force microscopy (C-AFM) at room temperature. The thin films with thickness ranged from 100 nm to 300 nm basically show cubic structures with a=0.3886 nm, the same as that of the raw material used, but the structures are highly modulated. C-AFM results revealed that the atomic scale p-n junction feature of the thin films was the same as that of the single crystals. The preparation of the thin films thus further confirms the possibility of their application extending from micrometer-sized single crystals to macroscopic thin film.
文摘We have successfully fabricated the colossal magnetoresistive (CMR) p-n junctions of perovskite oxide La0.9Sr0.1MnO3/SrNb0.01Ti0.99O3 (LSMO/SNTO) with laser molecular beam epitaxy. The I-V characteristics of the LSMO/SNTO p-n junctions as a function of applied magnetic field (05 T) were studied between 100 and 300 K. We found that the p-n junction exhibited the CMR behavior. The CMR ratio rR/R0 (rR = RH - R0) is positive in magnetic fields below 0.13 T and at high temperature, while it displays a negative CMR near 100 K and in magnetic fields over 0.13 T. The CMR ratio values are 8% at 0.1 T and 13% at 5 T and 300 K, 40% at 0.1 T and 150 K, 10% at 0.13 T and 60% at 5 T and 100 K. The CMR behavior of the p-n junction is different from those of the LaMnO3 compound family.
基金supported by the National Natural Science Foundation of China(Grant No.10334070).
文摘Nanosecond (ns) photoelectric effects have been observed in all-oxide p-n junctions of La0.9Sr0.1MnO3/SrNb0.01Ti0.99O3 for the first time. The rise time was about 23 ns and the full width at half maximum was about 125 ns for the open-circuit photovoltaic pulse when the La0.9Sr0.1MnO3 thin film in the p-n junction was irradiated by a laser of ~20 ns pulse duration and 308 nm wavelength. The photovoltaic sensitivity was 80 mV/mJ for a 308 nm laser pulse.