{"title":"超流体他","authors":"I. Kenyon","doi":"10.1093/oso/9780198808350.003.0014","DOIUrl":null,"url":null,"abstract":"The superfluid transition of 4He at 2.17K to He-II and the inference of an underlying condensate are introduced. The fountain effect is interpreted. Andronikashvili’s experiment and the determination of superfluid fraction versus temperature are discussed. Sound and second sound are described. Relationships between the condensate and superfluid fractions, and to off diagonal long-range order (ODLRO) are deduced. The revelation of topological quantization of circulation by Vinen’s experiment is recounted. Spontaneous symmetry breaking by the condensate’s phase coherence is explained. Excitations and their dispersion relations described with Landau’s interpretation, including the explanation of the critical velocity of superflow. Vortices, their interpretation in terms of quantized circulation, and their visualization are described.","PeriodicalId":165376,"journal":{"name":"Quantum 20/20","volume":"101 1","pages":"0"},"PeriodicalIF":0.0000,"publicationDate":"2019-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Superfluid 4He\",\"authors\":\"I. Kenyon\",\"doi\":\"10.1093/oso/9780198808350.003.0014\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"The superfluid transition of 4He at 2.17K to He-II and the inference of an underlying condensate are introduced. The fountain effect is interpreted. Andronikashvili’s experiment and the determination of superfluid fraction versus temperature are discussed. Sound and second sound are described. Relationships between the condensate and superfluid fractions, and to off diagonal long-range order (ODLRO) are deduced. The revelation of topological quantization of circulation by Vinen’s experiment is recounted. Spontaneous symmetry breaking by the condensate’s phase coherence is explained. Excitations and their dispersion relations described with Landau’s interpretation, including the explanation of the critical velocity of superflow. Vortices, their interpretation in terms of quantized circulation, and their visualization are described.\",\"PeriodicalId\":165376,\"journal\":{\"name\":\"Quantum 20/20\",\"volume\":\"101 1\",\"pages\":\"0\"},\"PeriodicalIF\":0.0000,\"publicationDate\":\"2019-09-10\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Quantum 20/20\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://doi.org/10.1093/oso/9780198808350.003.0014\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"\",\"JCRName\":\"\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Quantum 20/20","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1093/oso/9780198808350.003.0014","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
The superfluid transition of 4He at 2.17K to He-II and the inference of an underlying condensate are introduced. The fountain effect is interpreted. Andronikashvili’s experiment and the determination of superfluid fraction versus temperature are discussed. Sound and second sound are described. Relationships between the condensate and superfluid fractions, and to off diagonal long-range order (ODLRO) are deduced. The revelation of topological quantization of circulation by Vinen’s experiment is recounted. Spontaneous symmetry breaking by the condensate’s phase coherence is explained. Excitations and their dispersion relations described with Landau’s interpretation, including the explanation of the critical velocity of superflow. Vortices, their interpretation in terms of quantized circulation, and their visualization are described.