{"title":"安德烈耶夫隧道穿越单一电子态诱导的空间相关隙内态","authors":"Ruixia Zhong, Zhongzheng Yang, Qi Wang, Fanbang Zheng, Wenhui Li, Juefei Wu, Chenhaoping Wen, Xi Chen, Yanpeng Qi* and Shichao Yan*, ","doi":"10.1021/acs.nanolett.4c01581","DOIUrl":null,"url":null,"abstract":"<p >By using low-temperature scanning tunneling microscopy and spectroscopy (STM/STS), we observe in-gap states induced by Andreev tunneling through a single impurity state in a low carrier density superconductor (NaAlSi). The energy-symmetric in-gap states appear when the impurity state is located within the superconducting gap. In-gap states can cross the Fermi level, and they show X-shaped spatial variation. We interpret the in-gap states as a consequence of the Andreev tunneling through the impurity state, which involves the formation or breakup of a Cooper pair. Due to the low carrier density in NaAlSi, the in-gap state is tunable by controlling the STM tip–sample distance. Under strong external magnetic fields, the impurity state shows Zeeman splitting when it is located near the Fermi level. Our findings not only demonstrate the Andreev tunneling involving single electronic state but also provide new insights for understanding the spatially dependent in-gap states in low carrier density superconductors.</p>","PeriodicalId":53,"journal":{"name":"Nano Letters","volume":null,"pages":null},"PeriodicalIF":9.6000,"publicationDate":"2024-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Spatially Dependent in-Gap States Induced by Andreev Tunneling through a Single Electronic State\",\"authors\":\"Ruixia Zhong, Zhongzheng Yang, Qi Wang, Fanbang Zheng, Wenhui Li, Juefei Wu, Chenhaoping Wen, Xi Chen, Yanpeng Qi* and Shichao Yan*, \",\"doi\":\"10.1021/acs.nanolett.4c01581\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p >By using low-temperature scanning tunneling microscopy and spectroscopy (STM/STS), we observe in-gap states induced by Andreev tunneling through a single impurity state in a low carrier density superconductor (NaAlSi). The energy-symmetric in-gap states appear when the impurity state is located within the superconducting gap. In-gap states can cross the Fermi level, and they show X-shaped spatial variation. We interpret the in-gap states as a consequence of the Andreev tunneling through the impurity state, which involves the formation or breakup of a Cooper pair. Due to the low carrier density in NaAlSi, the in-gap state is tunable by controlling the STM tip–sample distance. Under strong external magnetic fields, the impurity state shows Zeeman splitting when it is located near the Fermi level. Our findings not only demonstrate the Andreev tunneling involving single electronic state but also provide new insights for understanding the spatially dependent in-gap states in low carrier density superconductors.</p>\",\"PeriodicalId\":53,\"journal\":{\"name\":\"Nano Letters\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":9.6000,\"publicationDate\":\"2024-07-05\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Nano Letters\",\"FirstCategoryId\":\"88\",\"ListUrlMain\":\"https://pubs.acs.org/doi/10.1021/acs.nanolett.4c01581\",\"RegionNum\":1,\"RegionCategory\":\"材料科学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"CHEMISTRY, MULTIDISCIPLINARY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Nano Letters","FirstCategoryId":"88","ListUrlMain":"https://pubs.acs.org/doi/10.1021/acs.nanolett.4c01581","RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"CHEMISTRY, MULTIDISCIPLINARY","Score":null,"Total":0}
引用次数: 0
摘要
通过使用低温扫描隧道显微镜和光谱学(STM/STS),我们在低载流子密度超导体(NaAlSi)中观察到了安德烈耶夫隧道通过单一杂质态诱导的隙内态。当杂质态位于超导间隙内时,就会出现能量对称的内隙态。内隙态可以跨越费米级,并呈现出 X 型空间变化。我们将这些内隙态解释为安德烈耶夫隧穿杂质态的结果,其中涉及库珀对的形成或断裂。由于 NaAlSi 中的载流子密度较低,因此可通过控制 STM 尖端与样品的距离来调整内隙态。在强外部磁场作用下,杂质态位于费米级附近时会出现泽曼分裂。我们的发现不仅证明了涉及单电子态的安德烈耶夫隧道现象,而且为理解低载流子密度超导体中空间依赖性内隙态提供了新的见解。
Spatially Dependent in-Gap States Induced by Andreev Tunneling through a Single Electronic State
By using low-temperature scanning tunneling microscopy and spectroscopy (STM/STS), we observe in-gap states induced by Andreev tunneling through a single impurity state in a low carrier density superconductor (NaAlSi). The energy-symmetric in-gap states appear when the impurity state is located within the superconducting gap. In-gap states can cross the Fermi level, and they show X-shaped spatial variation. We interpret the in-gap states as a consequence of the Andreev tunneling through the impurity state, which involves the formation or breakup of a Cooper pair. Due to the low carrier density in NaAlSi, the in-gap state is tunable by controlling the STM tip–sample distance. Under strong external magnetic fields, the impurity state shows Zeeman splitting when it is located near the Fermi level. Our findings not only demonstrate the Andreev tunneling involving single electronic state but also provide new insights for understanding the spatially dependent in-gap states in low carrier density superconductors.
期刊介绍:
Nano Letters serves as a dynamic platform for promptly disseminating original results in fundamental, applied, and emerging research across all facets of nanoscience and nanotechnology. A pivotal criterion for inclusion within Nano Letters is the convergence of at least two different areas or disciplines, ensuring a rich interdisciplinary scope. The journal is dedicated to fostering exploration in diverse areas, including:
- Experimental and theoretical findings on physical, chemical, and biological phenomena at the nanoscale
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- Realization of integrated nanostructures and nano-engineered devices exhibiting advanced performance
- Applications of nanoscale materials in living and environmental systems
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