We quantitatively investigate the third-order optical nonlinear response of Co-doped ZnO thin films prepared by magnetron sputtering using the Z-scan method. The two-photon absorption and optical Kerr effect are revea...We quantitatively investigate the third-order optical nonlinear response of Co-doped ZnO thin films prepared by magnetron sputtering using the Z-scan method. The two-photon absorption and optical Kerr effect are revealed to contribute to the third-order nonlinear response of the Co-doped ZnO films. The nonlinear absorption coefficient β is determined to be approximately 8.8 × 10-5 cm/W and the third-order nonlinear susceptibility X（3） is 2.93 × 10-6 esu. The defect-associated energy levels within the band gap are suggested to be responsible for the enhanced nonlinear response observed in Co-doped ZnO films.展开更多
The effect of cobalt-doping on the magnetic,transport and magnetoresistance characteristics of La1-xSrxMnO3 was investigated.The results show that the magnetoelectric property of rare-earth doped manganites is greatly...The effect of cobalt-doping on the magnetic,transport and magnetoresistance characteristics of La1-xSrxMnO3 was investigated.The results show that the magnetoelectric property of rare-earth doped manganites is greatly affected by substitution of Co for Mn sites.The Curie temperature as well as the magnetic moment decreases with the increase of doping concentration,and the samples exhibit obvious characteristics of the spin glass state.Moreover,the magnetoresistance is evidently modulated by doping concentration,and the relevant temperature dependence is also suppressed.In addition,low-temperature magnetoresistance is significantly promoted as doping concentration increases,which renders a value of approximately 50% in the temperature range of 5-200 K and varies within 12.5%.It can be attributed to the effect of spin scattering, induced by cobalt doping,on the itinerant electrons of Mn ions,thus introducing a spin-disorder region into the ferromagnetic region of double-exchange interaction between neighbouring Mn^3＋ and Mn^4＋ ions.展开更多
基金Supported by National Basic Research Program of China under Grant Nos 2011CB922200 and 2013CB922303
文摘We quantitatively investigate the third-order optical nonlinear response of Co-doped ZnO thin films prepared by magnetron sputtering using the Z-scan method. The two-photon absorption and optical Kerr effect are revealed to contribute to the third-order nonlinear response of the Co-doped ZnO films. The nonlinear absorption coefficient β is determined to be approximately 8.8 × 10-5 cm/W and the third-order nonlinear susceptibility X（3） is 2.93 × 10-6 esu. The defect-associated energy levels within the band gap are suggested to be responsible for the enhanced nonlinear response observed in Co-doped ZnO films.
基金Project suppprted by the doctor start-up fund of the Southwest University of Science and Technology of China (Grant No07ZX0110)
文摘The effect of cobalt-doping on the magnetic,transport and magnetoresistance characteristics of La1-xSrxMnO3 was investigated.The results show that the magnetoelectric property of rare-earth doped manganites is greatly affected by substitution of Co for Mn sites.The Curie temperature as well as the magnetic moment decreases with the increase of doping concentration,and the samples exhibit obvious characteristics of the spin glass state.Moreover,the magnetoresistance is evidently modulated by doping concentration,and the relevant temperature dependence is also suppressed.In addition,low-temperature magnetoresistance is significantly promoted as doping concentration increases,which renders a value of approximately 50% in the temperature range of 5-200 K and varies within 12.5%.It can be attributed to the effect of spin scattering, induced by cobalt doping,on the itinerant electrons of Mn ions,thus introducing a spin-disorder region into the ferromagnetic region of double-exchange interaction between neighbouring Mn^3＋ and Mn^4＋ ions.
