arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2412.03047cond-mat.mtrl-scicond-mat.other
收藏

(111)和(001)-NiO薄膜的类块体结构、磁性与光学性质

Bulk-like structural, magnetic and optical properties of (111)- and (001)-NiO thin films

S. Kaur, Smriti Bhatia, Pooja, Kshitij Sharma, V. K. Malik, J. P. Singh, K. Sen

AI总结:

该研究用PLD制备(111)和(001)取向NiO薄膜,通过磁性、拉曼、带隙及光致发光表征证明其在30 nm厚度下仍保持类块体性质并可能存在激子-磁振子耦合。

摘要:

我们分别利用脉冲激光沉积(PLD)在(0001)-蓝宝石和(001)-MgO衬底上生长了(111)和(001)取向的NiO薄膜。直流磁化率测量表明,样品的奈尔温度高于室温。这些薄膜在环境条件下存在双磁振子拉曼散射模式,进一步证实了这一点。此外,至少在厚度薄至30 nm时,薄膜中双磁振子模式相对于邻近声子模式的相对强度与块体NiO中的相应值相当。紫外-可见光谱和椭圆偏振光谱测定,薄膜的带隙为3.6 eV,完全处于块体NiO的范围内。因此,这些结果表明该薄膜具有类块体特性。此外,对(111)-NiO薄膜的光致发光测量获得了位于385和405 nm的两个辐射跃迁。后者的线宽随温度降低而展宽,表明可能存在激子-磁振子耦合。总体而言,这些由PLD生长的氧化物薄膜因其光学透明性以及在室温下承载稳健磁振子的能力而具有重要的技术意义。

英文摘要:

We have grown (111)- and (001)-oriented NiO thin films on (0001)-Sapphire and (001)-MgO substrates using pulsed laser deposition (PLD), respectively. DC magnetic susceptibility measurements underline that the Néel temperatures of the samples are beyond room-temperature. This is further confirmed by the presence of two-magnon Raman scattering modes in these films in ambient conditions. Moreover, relative intensity of the two magnon-mode with respect to a neighboring phonon mode in the films, at least down to 30 nm thickness, is comparable to the same for bulk NiO. UV-vis spectroscopy and spectroscopic ellipsometry determined that the bandgap of the films is 3.6 eV which is well within the range for bulk NiO. Thus, these indicate that the thin films are bulk-like. Further, photoluminescence measurements on (111)-NiO films obtained two-radiative transitions at 385 and 405 nm. The linewidth of the latter broadens towards low temperatures, indicating a plausible exciton-magnon coupling. Overall, these PLD-grown oxide films hold significant technological importance due to their optical transparency and their capacity to host robust magnons at room temperature.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑