{"title":"通过法拉第几何太赫兹磁光测量确定蓝宝石衬底上 2H 堆积双层 MoS2 的关键电子参数","authors":"Xingjia Cheng, Wen Xu, Hua Wen, Jing Zhang, Heng Zhang, Haowen Li, Francois M. Peeters","doi":"10.1007/s11467-024-1425-4","DOIUrl":null,"url":null,"abstract":"<div><p>Bilayer (BL) transition metal dichalcogenides (TMDs) are important materials in valleytronics and twistronics. Here we study terahertz (THz) magneto-optical (MO) properties of n-type 2<i>H</i>-stacking BL molybdenum sulfide (MoS<sub>2</sub>) on sapphire substrate grown by chemical vapor deposition. The AFM, Raman spectroscopy and photoluminescence are used for characterization of the samples. Applying THz time-domain spectroscopy (TDS), in combination with polarization test and the presence of magnetic field in Faraday geometry, THz MO transmissions through the sample are measured from 0 to 8 T at 80 K. The complex right- and left-handed circular MO conductivities for 2<i>H</i>-stacking BL MoS<sub>2</sub> are obtained. Through fitting the experimental results with theoretical formula of MO conductivities for an electron gas, generalized by us previously through the inclusion of photon-induced electronic backscattering effect, we are able to determine magneto-optically the key electronic parameters of BL MoS<sub>2</sub>, such as the electron density <i>n</i><sub><i>e</i></sub>, the electronic relaxation time <i>τ</i>, the electronic localization factor <i>c</i> and, particularly, the effective electron mass <i>m*</i> around <i>Q</i>-point in between the <i>K</i>- and Γ-point in the electronic band structure. The dependence of these parameters upon magnetic field is examined and analyzed. This is a pioneering experimental work to measure <i>m*</i> around the <i>Q</i>-point in 2<i>H</i>-stacking BL MoS<sub>2</sub> and the experimental value is very close to that obtained theoretically. We find that <i>n</i><sub><i>e</i></sub>/<i>τ</i>/ ∣ <i>c</i> ∣ /<i>m*</i> in 2<i>H</i>-stacking BL MoS<sub>2</sub> decreases/increases/decreases/increases with increasing magnetic field. The results obtained from this study can be benefit to us in gaining an in-depth understanding of the electronic and optoelectronic properties of BL TMD systems.\n</p><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":573,"journal":{"name":"Frontiers of Physics","volume":"19 6","pages":""},"PeriodicalIF":6.5000,"publicationDate":"2024-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Key electronic parameters of 2H-stacking bilayer MoS2 on sapphire substrate determined by terahertz magneto-optical measurement in Faraday geometry\",\"authors\":\"Xingjia Cheng, Wen Xu, Hua Wen, Jing Zhang, Heng Zhang, Haowen Li, Francois M. Peeters\",\"doi\":\"10.1007/s11467-024-1425-4\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><p>Bilayer (BL) transition metal dichalcogenides (TMDs) are important materials in valleytronics and twistronics. Here we study terahertz (THz) magneto-optical (MO) properties of n-type 2<i>H</i>-stacking BL molybdenum sulfide (MoS<sub>2</sub>) on sapphire substrate grown by chemical vapor deposition. The AFM, Raman spectroscopy and photoluminescence are used for characterization of the samples. Applying THz time-domain spectroscopy (TDS), in combination with polarization test and the presence of magnetic field in Faraday geometry, THz MO transmissions through the sample are measured from 0 to 8 T at 80 K. The complex right- and left-handed circular MO conductivities for 2<i>H</i>-stacking BL MoS<sub>2</sub> are obtained. Through fitting the experimental results with theoretical formula of MO conductivities for an electron gas, generalized by us previously through the inclusion of photon-induced electronic backscattering effect, we are able to determine magneto-optically the key electronic parameters of BL MoS<sub>2</sub>, such as the electron density <i>n</i><sub><i>e</i></sub>, the electronic relaxation time <i>τ</i>, the electronic localization factor <i>c</i> and, particularly, the effective electron mass <i>m*</i> around <i>Q</i>-point in between the <i>K</i>- and Γ-point in the electronic band structure. The dependence of these parameters upon magnetic field is examined and analyzed. This is a pioneering experimental work to measure <i>m*</i> around the <i>Q</i>-point in 2<i>H</i>-stacking BL MoS<sub>2</sub> and the experimental value is very close to that obtained theoretically. We find that <i>n</i><sub><i>e</i></sub>/<i>τ</i>/ ∣ <i>c</i> ∣ /<i>m*</i> in 2<i>H</i>-stacking BL MoS<sub>2</sub> decreases/increases/decreases/increases with increasing magnetic field. The results obtained from this study can be benefit to us in gaining an in-depth understanding of the electronic and optoelectronic properties of BL TMD systems.\\n</p><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>\",\"PeriodicalId\":573,\"journal\":{\"name\":\"Frontiers of Physics\",\"volume\":\"19 6\",\"pages\":\"\"},\"PeriodicalIF\":6.5000,\"publicationDate\":\"2024-07-18\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Frontiers of Physics\",\"FirstCategoryId\":\"101\",\"ListUrlMain\":\"https://link.springer.com/article/10.1007/s11467-024-1425-4\",\"RegionNum\":2,\"RegionCategory\":\"物理与天体物理\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"PHYSICS, MULTIDISCIPLINARY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Frontiers of Physics","FirstCategoryId":"101","ListUrlMain":"https://link.springer.com/article/10.1007/s11467-024-1425-4","RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"PHYSICS, MULTIDISCIPLINARY","Score":null,"Total":0}
引用次数: 0
摘要
双层(BL)过渡金属二卤化物(TMD)是谷光和双电子学中的重要材料。在此,我们研究了通过化学气相沉积法在蓝宝石衬底上生长的 n 型 2H 叠层 BL 硫化钼(MoS2)的太赫兹(THz)磁光(MO)特性。样品的表征采用了原子力显微镜、拉曼光谱和光致发光技术。应用太赫兹时域光谱(TDS),结合极化测试和法拉第几何中的磁场存在,测量了样品在 80 K 下从 0 到 8 T 的太赫兹 MO 透射率。通过将实验结果与我们之前通过加入光子诱导的电子反向散射效应而归纳出的电子气 MO 导率理论公式进行拟合,我们能够通过磁光确定 BL MoS2 的关键电子参数,如电子密度 ne、电子弛豫时间 τ、电子局域因子 c,尤其是电子带结构中介于 K 点和Γ点之间的 Q 点附近的有效电子质量 m*。研究分析了这些参数对磁场的依赖性。这是一项测量 2H 叠层 BL MoS2 中 Q 点附近 m* 的开创性实验工作,实验值与理论值非常接近。我们发现 2H 叠层 BL MoS2 中的 ne/τ/ ∣ c ∣ /m* 随着磁场的增加而减小/增大/减小/增大。这项研究的结果有助于我们深入了解 BL TMD 系统的电子和光电特性。
Key electronic parameters of 2H-stacking bilayer MoS2 on sapphire substrate determined by terahertz magneto-optical measurement in Faraday geometry
Bilayer (BL) transition metal dichalcogenides (TMDs) are important materials in valleytronics and twistronics. Here we study terahertz (THz) magneto-optical (MO) properties of n-type 2H-stacking BL molybdenum sulfide (MoS2) on sapphire substrate grown by chemical vapor deposition. The AFM, Raman spectroscopy and photoluminescence are used for characterization of the samples. Applying THz time-domain spectroscopy (TDS), in combination with polarization test and the presence of magnetic field in Faraday geometry, THz MO transmissions through the sample are measured from 0 to 8 T at 80 K. The complex right- and left-handed circular MO conductivities for 2H-stacking BL MoS2 are obtained. Through fitting the experimental results with theoretical formula of MO conductivities for an electron gas, generalized by us previously through the inclusion of photon-induced electronic backscattering effect, we are able to determine magneto-optically the key electronic parameters of BL MoS2, such as the electron density ne, the electronic relaxation time τ, the electronic localization factor c and, particularly, the effective electron mass m* around Q-point in between the K- and Γ-point in the electronic band structure. The dependence of these parameters upon magnetic field is examined and analyzed. This is a pioneering experimental work to measure m* around the Q-point in 2H-stacking BL MoS2 and the experimental value is very close to that obtained theoretically. We find that ne/τ/ ∣ c ∣ /m* in 2H-stacking BL MoS2 decreases/increases/decreases/increases with increasing magnetic field. The results obtained from this study can be benefit to us in gaining an in-depth understanding of the electronic and optoelectronic properties of BL TMD systems.
期刊介绍:
Frontiers of Physics is an international peer-reviewed journal dedicated to showcasing the latest advancements and significant progress in various research areas within the field of physics. The journal's scope is broad, covering a range of topics that include:
Quantum computation and quantum information
Atomic, molecular, and optical physics
Condensed matter physics, material sciences, and interdisciplinary research
Particle, nuclear physics, astrophysics, and cosmology
The journal's mission is to highlight frontier achievements, hot topics, and cross-disciplinary points in physics, facilitating communication and idea exchange among physicists both in China and internationally. It serves as a platform for researchers to share their findings and insights, fostering collaboration and innovation across different areas of physics.