{"title":"通过与栅极电压控制双层石墨烯中漂移传导电子的相互作用放大表面声波","authors":"","doi":"10.1016/j.physb.2024.416585","DOIUrl":null,"url":null,"abstract":"<div><div>A theoretical study is presented on the amplification of surface acoustic waves (SAWs) due to their interaction with conduction electrons in gate voltage-controlled bilayer graphene (BLG) in the presence of a dc electric field applied to the BLG sample. Using the Green’s function method, the SAW gain is calculated depending on the density of conduction electrons and the band gap in the electronic spectrum of BLG. It is found that the bias voltage-induced band gap opening in BLG significantly increases the SAW gain, which can be almost four times that of unbiased BLG at room temperature, provided the electron density is not too high (<span><math><mrow><mo>≲</mo><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mn>12</mn></mrow></msup></mrow></math></span> cm<sup>−2</sup>). The theory developed also shows that the electron density dependence of the SAW gain is non-monotonic: as the electron density increases from <span><math><mrow><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mn>11</mn></mrow></msup></mrow></math></span> to <span><math><mrow><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mn>13</mn></mrow></msup></mrow></math></span> cm<sup>−2</sup>, the gain first increases, reaching a maximum, and then decreases.</div></div>","PeriodicalId":20116,"journal":{"name":"Physica B-condensed Matter","volume":null,"pages":null},"PeriodicalIF":2.8000,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Amplification of surface acoustic waves through interaction with drifting conduction electrons in gate voltage-controlled bilayer graphene\",\"authors\":\"\",\"doi\":\"10.1016/j.physb.2024.416585\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><div>A theoretical study is presented on the amplification of surface acoustic waves (SAWs) due to their interaction with conduction electrons in gate voltage-controlled bilayer graphene (BLG) in the presence of a dc electric field applied to the BLG sample. Using the Green’s function method, the SAW gain is calculated depending on the density of conduction electrons and the band gap in the electronic spectrum of BLG. It is found that the bias voltage-induced band gap opening in BLG significantly increases the SAW gain, which can be almost four times that of unbiased BLG at room temperature, provided the electron density is not too high (<span><math><mrow><mo>≲</mo><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mn>12</mn></mrow></msup></mrow></math></span> cm<sup>−2</sup>). The theory developed also shows that the electron density dependence of the SAW gain is non-monotonic: as the electron density increases from <span><math><mrow><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mn>11</mn></mrow></msup></mrow></math></span> to <span><math><mrow><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mn>13</mn></mrow></msup></mrow></math></span> cm<sup>−2</sup>, the gain first increases, reaching a maximum, and then decreases.</div></div>\",\"PeriodicalId\":20116,\"journal\":{\"name\":\"Physica B-condensed Matter\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":2.8000,\"publicationDate\":\"2024-10-01\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Physica B-condensed Matter\",\"FirstCategoryId\":\"101\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S0921452624009268\",\"RegionNum\":3,\"RegionCategory\":\"物理与天体物理\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q2\",\"JCRName\":\"PHYSICS, CONDENSED MATTER\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Physica B-condensed Matter","FirstCategoryId":"101","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0921452624009268","RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"PHYSICS, CONDENSED MATTER","Score":null,"Total":0}
Amplification of surface acoustic waves through interaction with drifting conduction electrons in gate voltage-controlled bilayer graphene
A theoretical study is presented on the amplification of surface acoustic waves (SAWs) due to their interaction with conduction electrons in gate voltage-controlled bilayer graphene (BLG) in the presence of a dc electric field applied to the BLG sample. Using the Green’s function method, the SAW gain is calculated depending on the density of conduction electrons and the band gap in the electronic spectrum of BLG. It is found that the bias voltage-induced band gap opening in BLG significantly increases the SAW gain, which can be almost four times that of unbiased BLG at room temperature, provided the electron density is not too high ( cm−2). The theory developed also shows that the electron density dependence of the SAW gain is non-monotonic: as the electron density increases from to cm−2, the gain first increases, reaching a maximum, and then decreases.
期刊介绍:
Physica B: Condensed Matter comprises all condensed matter and material physics that involve theoretical, computational and experimental work.
Papers should contain further developments and a proper discussion on the physics of experimental or theoretical results in one of the following areas:
-Magnetism
-Materials physics
-Nanostructures and nanomaterials
-Optics and optical materials
-Quantum materials
-Semiconductors
-Strongly correlated systems
-Superconductivity
-Surfaces and interfaces