{"title":"First-principles calculations of the structural and electronic properties of monolayer 1T−MoO2 and WO2","authors":"Yi-Chi Li, Jian Zhou","doi":"10.1103/physrevb.110.045447","DOIUrl":null,"url":null,"abstract":"Two-dimensional transition metal dichalcogenides (TMDCs), such as <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msub><mi>MoS</mi><mn>2</mn></msub></math> and <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msub><mi>WTe</mi><mn>2</mn></msub></math>, received extensive attention owing to their diverse crystal structures and intriguing physical properties. In contrast, there has been relatively limited research on transition-metal dioxides (TMDOs) despite sharing the same crystal structures with TMDCs. Here, we investigate the structural and electronic properties of monolayer <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><mi>T</mi></mrow></math>-phase <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msub><mi>MoO</mi><mn>2</mn></msub></math> and <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msub><mi>WO</mi><mn>2</mn></msub></math> using first-principles calculations. Our analysis reveals that their phonon dispersions have prominent imaginary modes, leading to the emergence of two charge density wave phases: <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><mn>1</mn><msup><mrow><mtext mathvariant=\"italic\">T</mtext></mrow><mo>′</mo></msup></mrow></math> and <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><msqrt><mn>3</mn></msqrt><mo>×</mo><msqrt><mn>3</mn></msqrt></mrow></math>. Interestingly, we find that <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><mn>1</mn><msup><mtext mathvariant=\"italic\">T</mtext><mo>′</mo></msup><mtext>−</mtext><msub><mi>MoO</mi><mn>2</mn></msub></mrow></math> and <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msub><mi>WO</mi><mn>2</mn></msub></math> exhibit Dirac semimetal behavior, while their <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><msqrt><mn>3</mn></msqrt><mo>×</mo><msqrt><mn>3</mn></msqrt></mrow></math> phases are ferroelectric semiconductors, with out-of-plane spontaneous polarization of 3.99 and 3.94 pC/m, respectively. This work sheds light on structural and electronic properties of <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><mi>T</mi></mrow></math>-phase <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msub><mi>MoO</mi><mn>2</mn></msub></math> and <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msub><mi>WO</mi><mn>2</mn></msub></math>, offering valuable insights for further experimental investigations into similar TMDOs materials.","PeriodicalId":20082,"journal":{"name":"Physical Review B","volume":null,"pages":null},"PeriodicalIF":3.7000,"publicationDate":"2024-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Physical Review B","FirstCategoryId":"101","ListUrlMain":"https://doi.org/10.1103/physrevb.110.045447","RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"Physics and Astronomy","Score":null,"Total":0}
引用次数: 0
Abstract
Two-dimensional transition metal dichalcogenides (TMDCs), such as and , received extensive attention owing to their diverse crystal structures and intriguing physical properties. In contrast, there has been relatively limited research on transition-metal dioxides (TMDOs) despite sharing the same crystal structures with TMDCs. Here, we investigate the structural and electronic properties of monolayer -phase and using first-principles calculations. Our analysis reveals that their phonon dispersions have prominent imaginary modes, leading to the emergence of two charge density wave phases: and . Interestingly, we find that and exhibit Dirac semimetal behavior, while their phases are ferroelectric semiconductors, with out-of-plane spontaneous polarization of 3.99 and 3.94 pC/m, respectively. This work sheds light on structural and electronic properties of -phase and , offering valuable insights for further experimental investigations into similar TMDOs materials.
期刊介绍:
Physical Review B (PRB) is the world’s largest dedicated physics journal, publishing approximately 100 new, high-quality papers each week. The most highly cited journal in condensed matter physics, PRB provides outstanding depth and breadth of coverage, combined with unrivaled context and background for ongoing research by scientists worldwide.
PRB covers the full range of condensed matter, materials physics, and related subfields, including:
-Structure and phase transitions
-Ferroelectrics and multiferroics
-Disordered systems and alloys
-Magnetism
-Superconductivity
-Electronic structure, photonics, and metamaterials
-Semiconductors and mesoscopic systems
-Surfaces, nanoscience, and two-dimensional materials
-Topological states of matter