Proximity-Induced Shiba States in a Molecular Junction

Autor: Concepció Rovira, Joshua O. Island, Joeri de Bruijckere, Teun M. Klapwijk, Enrique Burzurí, Jaume Veciana, Carlos Franco, Ramón Aguado, Herre S. J. van der Zant, Rocco Gaudenzi, Marta Mas-Torrent
Přispěvatelé: Netherlands Organization for Scientific Research, Ministry of Education, Culture and Science (The Netherlands), European Research Council, Ministerio de Economía y Competitividad (España), Generalitat de Catalunya, Centro de Investigación Biomédica en Red Bioingeniería, Biomateriales y Nanomedicina (España), Ministry of Education and Science of the Russian Federation
Rok vydání: 2017
Předmět:
Superconductivity
Yu-Shiba-Rusinov states
Superconductivity
Yu-Shiba-Rusinov states
electron transport spectroscopy
radical molecules
Kondo effect
FOS: Physical sciences
General Physics and Astronomy
Proximity effect
02 engineering and technology
Spin-singlet pairing
01 natural sciences
Superconductivity (cond-mat.supr-con)
Paramagnetism
Magnetic interactions
Condensed Matter::Superconductivity
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
0103 physical sciences
Proximity effect (superconductivity)
Singlet state
010306 general physics
Physics
Condensed Matter - Mesoscale and Nanoscale Physics
Condensed matter physics
Condensed Matter - Superconductivity
radical molecules
Molecules
021001 nanoscience & nanotechnology
Excited state
Condensed Matter::Strongly Correlated Electrons
Cooper pair
electron transport spectroscopy
Molecular junctions
0210 nano-technology
Magnetic impurity
Zdroj: Digital.CSIC. Repositorio Institucional del CSIC
instname
Physical Review Letters, 118(11)
ISSN: 1079-7114
0031-9007
DOI: 10.1103/physrevlett.118.117001
Popis: Island, Joshua O. et al.
Superconductors containing magnetic impurities exhibit intriguing phenomena derived from the competition between Cooper pairing and Kondo screening. At the heart of this competition are the Yu-Shiba-Rusinov (Shiba) states which arise from the pair breaking effects a magnetic impurity has on a superconducting host. Hybrid superconductor-molecular junctions offer unique access to these states but the added complexity in fabricating such devices has kept their exploration to a minimum. Here, we report on the successful integration of a model spin 1 / 2 impurity, in the form of a neutral and stable all organic radical molecule, in proximity-induced superconducting break junctions. Our measurements reveal excitations which are characteristic of a spin-induced Shiba state due to the radical’s unpaired spin strongly coupled to a superconductor. By virtue of a variable molecule-electrode coupling, we access both the singlet and doublet ground states of the hybrid system which give rise to the doublet and singlet Shiba excited states, respectively. Our results show that Shiba states are a robust feature of the interaction between a paramagnetic impurity and a proximity-induced superconductor where the excited state is mediated by correlated electron-hole (Andreev) pairs instead of Cooper pairs.
The authors thank Jens Paaske for insightful discussions. The authors acknowledge financial support by the Dutch Organization for Fundamental research (FOM), the Ministry of Education, Culture, and Science (OCW), the Netherlands Organization for Scientific Research (NWO), and an ERC advanced grant (MolS@MolS). C. F., M.M.-T., C. R., and J. V. acknowledge the financial support from Spanish Ministry of Economy and Competitiveness, through the DGI (CTQ2013-40480-R) and Severo Ochoa Programme for Centres of Excellence in R&D (SEV-2015-0496), the Generalitat de Catalunya (2014SGR-17) and the Networking Research Center of Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN). T.M. K. acknowledges the support from the European Research Council Advanced Grant No. 339306 (METIQUM) and from the Ministry of Education and Science of the Russian Federation, Contract No. 14.B25.31.0007. R. A. acknowledges Grants No. FIS2012-33521 and No. FIS-2015-64654 (MINECO/FEDER).
Databáze: OpenAIRE
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