双轴应变调控下单层双面神结构MoSSe拉曼光谱的理论研究

doi:10.12422/j.issn.1672-6952.2024.01.006

摘要/Abstract

摘要：

单层双面神结构过渡金属硫化物具有低维度、高迁移率以及奇特的电子结构性质，因此其在电子学和光电子学器件方面具有潜在的应用前景。由单层双面神结构过渡金属硫化物和基底材料制成的器件，很容易因基底材料和单层双面神结构过渡金属硫化物的晶格失配，导致单层双面神结构过渡金属硫化物受基底材料的应力，因此通过拉曼散射系统研究双轴应变对单层双面神结构MoSSe物性的影响具有重要意义。系统研究了双轴调控下单层双面神结构MoSSe的原子结构、电子结构、声子结构和拉曼散射特性。结果表明，在双轴应变调控下，单层双面神结构MoSSe的电子能带带隙出现了直接与间接的转换；随着压应变的减小和拉应变的增加，3个拉曼特征峰（E¹、E²、A $11$ ）的频率都发生了单调红移，而A $12$ 的拉曼特征峰在压应变减小的过程中出现了反常的蓝移；随着压应变的减小和拉应变的增加，双重简并模式（E¹、E²）的拉曼强度单调增加，单重简并模式的拉曼强度单调减小，而A $11$ 的拉曼强度先减小再增加。针对这些具有普遍性和特殊性的应变效应，通过建模进行了研究。结果表明，基于特征峰频率和强度随应变的变化差异，可以通过特征峰之间的频率差和强度比，快速定量化双面神结构材料的应变类型和大小。

关键词: 双轴应变, 拉曼光谱, 单层双面神结构, 应力表征

Abstract:

Monolayer Janus transition metal disulfides have low dimension, high mobility, and peculiar electronic structure properties, which have potential applications in electronics and optoelectronic devices. In devices made of monolayer Janus transition metal disulfide and substrate materials,are usually stressed due to lattice mismatch between monolayer Janus transition metal disulfides and substrate, it is significant to study the strain effect on physical properties of monolayer Janus transition metal disulfides through Raman scattering.This paper systematically investigate the biaxial strain effect on the atomic structure, electronic structure and Raman spectra of monolayer Janus MoSSe. The results show that monolayer Janus MoSSe can exhibit a band gap transition from direct to indirect one under biaxial strain, due to both the energy shift of bonding orbitals between the top of the valence band and the bottom of the conduction band and the sensitivity to strain. This paper also thoroughly study the strain effect on the Raman shift and intensity of monolayer Janus MoSSe. It is found that under biaxial strain modulation from decreasing compressive to increasing tensile, for the Raman shift, the three peaks of E¹, E², and A $11$ red?shift, while the peak of A $12$ blue?shifts abnormally with decreasing compressive strain; for the intensity, the peak intensity of the doubly?degenerate modes (E¹,E²) increases monotonically, while singly?degenerate modes shows the opposite trend, except for the A $11$ which intensity decreases with decreasing compressive strain and then increases with tensile strain. This paper propose a simple model to comprehend the strain effect. This theoretical study may supply an effective means to quickly and quantitatively characterize the strain size and type in Janus materials through the frequency difference and intensity ratio between typical Raman peaks.

Key words: Biaxial strain, Raman spectroscopy, Janus monolayer, Strain characterization

中图分类号:

O482.31

孙薇, 孙鸿智, 赵波, 郭怀红. 双轴应变调控下单层双面神结构MoSSe拉曼光谱的理论研究[J]. 辽宁石油化工大学学报, 2024, 44(1): 35-42.

Wei SUN, Hongzhi SUN, Bo ZHAO, Huaihong GUO. Theoretical Study on Raman Spectra of Janus MoSSe Single⁃Layer under Bi⁃Axial Strain[J]. Journal of Liaoning Petrochemical University, 2024, 44(1): 35-42.

图/表 11

图1 单层双面神结构MoSSe

Fig.1 Atomic structure of Janus MoSSe single?layer

表1 单层双面神结构MoSSe所属C3v 点群的特征标表

Table 1 Character table of the C3v point group of Janus MoSSe single?layer

C₃_v	E	2C₃	3σ_v	红外活性基	拉曼活性基
A₁	1	1	1	z	z²,x²+y²
A₂	1	1	－1	R_z	—
E	2	－1	0	（x,y)(R_x,R_y )	(x²+y²,xy)(xz,yz)

表2 单层双面神结构MoSSe所属C3v 点群的对称分析结果

Table 2 Symmetry analysis of the C3v point group of Janus MoSSe single?layer

C₃_v	E	2C₃	3σ_v
χ^as	3	3	3
χ_vec	3	0	1
χ^vib	9	0	3

图2 单层双面神结构MoSSe的声子色散图

Fig.2 Phonon dispersion relation of Janus MoSSe single?layer

图3 单层双面神结构MoSSe在第一布里渊区中心Γ点的拉曼活性光学模的振动模式

Fig.3 Raman?active optical modes of Janus MoSSe single?layerat Γ point in the center of the first Brillouin Zone

图4 双轴应变下的单层双面神结构MoSSe的拉曼光谱以及E2、A12、A11的频谱放大图

Fig. 4 Raman spectra of Janus MoSSe single?layerat under biaxial strain and zoomed-in Raman spectra of E2、A12、A11

图5 双轴应变下的单层双面神结构MoSSe的4个拉曼光谱模的拉曼频率和拉曼强度随应变的变化曲线（a）拉曼频率（b）拉曼强度

Fig. 5 Bi?axial strain dependence of frequency and intensity of four Raman modes of Janus MoSSe single?layerat

图6 单层双面神结构MoSSe的拉曼振动模式E1与A12的拉曼频率差(Δω)及强度比(I( A12)/I( E1 )）随应变的变化曲线

Fig. 6 Strain dependence of frequency difference(Δω) and intensity ratio (I(A12)/I(E1)) between the Raman modes E1 and A12of Janus MoSSe single?layerat

图7 不同应变下单层双面神结构MoSSe的电子能带结构和态密度分波（DOS）

Fig.7 Electron band structure and density of states (DOS) of Janus MoSSe single?layerat under different strains

图8 单层双面神结构MoSSe的能隙Δg与应变ε的关系曲线

Fig.8 Strain ε dependence of energy band gap Δg of Janus MoSSe single?layerat

图9 单层双面神结构MoSSe的晶胞参数（d、θ）与应变ε的关系曲线（a） d （b） θ

Fig. 9 Strain ε dependence of cell parameters（d, θ） of Janus MoSSe single?layerat

参考文献 26

1	RIVERA P，SCHAIBLEY J R，JONES A M，et al.Observation of long⁃lived interlayer excitons in monolayer MoSe₂⁃WSe₂ heterostructures［J］.Nature Communications，2015，6（1）：6242.
2	郭怀红，赵波.拉曼光谱探究二维原子晶体结构和物性的研究进展［J］.辽宁石油化工大学学报，2018，38（6）：1⁃9.
	GUO H H，ZHAO B. Research progress of Raman spectroscopy in exploring structural and physical properties of two dimensional atomic crystal［J］. Journal of Liaoning Shihua University，2018，38（6）：1⁃9.
3	FARKOUS M，BIKEROUIN M，PHUNG H T T，et al.Electronic and optical properties of layered van der Waals heterostructure based on MS₂（M=Mo，W） monolayers［J］.Materials Research Express，2019，6（6）：065060.
4	XIA C X，XIONG W Q，DU J，et al.Universality of electronic characteristics and photocatalyst applications in the two⁃dimensional Janus transition metal dichalcogenides［J］.Physical Review B，2018，98（16）：165424.
5	CAI H F，GUO Y F，GAO H J，et al.Tribo⁃piezoelectricity in Janus transition metal dichalcogenide bilayers：A first⁃principles study［J］.Nano Energy，2019，56：33⁃39.
6	KANDEMIR A，SAHIN H.Bilayers of Janus WSSe：Monitoring the stacking type via the vibrational spectrum［J］.Physical Chemistry Chemical Physics，2018，20（25）：17380⁃17386.
7	LEE C，YAN H G，BRUS L E，et al.Anomalous lattice vibrations of single⁃and few⁃layer MoS₂［J］.ACS Nano，2010，4（5）：2695⁃2700.
8	Molina⁃Sánchez A，WIRTZ L.Phonons in single and few⁃layer MoS₂ and WS₂［J］.Physical Review B，2011，84（15）： 155413.
9	ZHU Z Y，CHENG Y C，SCHWINGENSCHLÖGL U.Giant spin⁃orbit⁃induced spin splitting in two⁃dimensional transition⁃metal dichalcogenide semiconductors［J］.Physical Review B，2011，84（15）：153402.
10	HUANG J Q，LIU Z Y，YANG T，et al.New selection rule of resonant Raman scattering in MoS₂ monolayer under circular polarization［J］.Journal of Materials Science & Technology，2022，102：132⁃136.
11	ZHAO Y，ZHANG S S，SHI Y P，et al.Characterization of excitonic nature in Raman spectra using circularly polarized light［J］.ACS Nano，2020，14（8）：10527⁃10535.
12	孙鸿智，孙薇，赵波，等.单层Janus MoSSe双共振拉曼散射的理论研究［J］.辽宁石油化工大学学报，2022，42（3）：30⁃36.
	SUN H Z，SUN W，ZHAO B，et al. Theoretical study on double resonant Raman scattering in Janus MoSSe monolayer［J］. Journal of Liaoning Petrochemical University，2022，42（3）：30⁃36.
13	MOHIUDDIN T M G，LOMBARDO A，NAIR R R，et al.Uniaxial strain in graphene by Raman spectroscopy：G peak splitting，Grüneisen parameters， and sample orientation［J］.Physical Review B，2009，79（20）：205433.
14	JOHARI P，SHENOY V B.Tuning the electronic properties of semiconducting transition metal dichalcogenides by applying mechanical strains［J］.ACS Nano，2012，6（6）：5449⁃5456.
15	BERTOLAZZI S，BRIVIO J，KIS A.Stretching and breaking of ultrathin MoS₂［J］.ACS Nano，2011，5（12）：9703⁃9709.
16	LIU H T，HUANG Z Y，HE C Y，et al.Strain engineering the structures and electronic properties of Janus monolayer transition⁃metal dichalcogenides［J］.Journal of Applied Physics，2019，125（8）：082516.
17	ZHANG Y，GUO H H，SUN W，et al.Scaling law for strain dependence of Raman spectra in transition⁃metal dichalcogenides［J］.Journal of Raman Spectroscopy，2020，51（8）：1353⁃1361.
18	AMIN B，KALONI T P，SCHWINGENSCHLÖGL U.Strain engineering of WS₂，WSe₂，and WTe₂［J］.RSC Advances， 2014，4（65）：34561⁃34565.
19	GUO S D，DONG J.Biaxial strain tuned electronic structures and power factor in Janus transition metal dichalchogenide monolayers［J］.Semiconductor Science and Technology，2018，33（8）：085003.
20	LU A Y，ZHU H Y，XIAO J，et al.Janus monolayers of transition metal dichalcogenides［J］.Nature Nanotechnology，2017， 12（8）：744⁃749.
21	ZHANG J，JIA S，KHOLMANOV I，et al.Janus monolayer transition⁃metal dichalcogenides［J］.ACS Nano，2017，11（8）： 8192⁃8198.
22	JI Y J，YANG M Y，LIN H P，et al.Janus structures of transition metal dichalcogenides as the heterojunction photocatalysts for water splitting［J］.The Journal of Physical Chemistry C，2018，122（5）：3123⁃3129.
23	LI F P，WEI W，ZHAO P，et al.Electronic and optical properties of pristine and vertical and lateral heterostructures of Janus MoSSe and WSSe［J］.The Journal of Physical Chemistry Letters，2017，8（23）：5959⁃5965.
24	GIANNOZZI P，BARONI S，BONINI N，et al.QUANTUM ESPRESSO：A modular and open⁃source software project for quantum simulations of materials［J］.Journal of Physics：Condensed Matter，2009，21（39）：395502.
25	BLÖCHL P E.Projector augmented⁃wave method［J］.Physical Review B，1994，50（24）：17953.
26	MONKHORST H J，PACK J D.Special points for Brillouin⁃zone integrations［J］.Physical Review B，1976，13（12）：5188.

[1]	王国良, 韩伟航, 李存磊. 基于拉曼光谱与PLS的钻井液混合物定量分析[J]. 辽宁石油化工大学学报, 2022, 42(1): 78-85.
[2]	付紫微, 安保印, 杨占旭, 喻倩, 孔宪明. 磁性Fe⁃Au复合材料的制备及SERS性能[J]. 辽宁石油化工大学学报, 2020, 40(1): 26-30.
[3]	郭怀红，赵波. 拉曼光谱探究二维原子晶体结构和物性的研究进展[J]. 辽宁石油化工大学学报, 2018, 38(06): 1-09.