Superconductivity and Fermi Surface Studies of <i>β</i><sup>″</sup>-(BEDT-TTF)<sub>2</sub>[(H<sub>2</sub>O)(NH<sub>4</sub>)<sub>2</sub>Cr(C<sub>2</sub>O<sub>4</sub>)<sub>3</sub>]·18-Crown-6
We report rf-penetration depth measurements of the quasi-2D organic superconductor <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msup><mi>β</mi><mo>″</mo></msup></...
| Main Authors: | , , , , , |
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| Format: | Article |
| Language: | English |
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MDPI AG
2023-02-01
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| Series: | Magnetochemistry |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2312-7481/9/3/64 |
| _version_ | 1827748970573594624 |
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| author | Brett Laramee Raju Ghimire David Graf Lee Martin Toby J. Blundell Charles C. Agosta |
| author_facet | Brett Laramee Raju Ghimire David Graf Lee Martin Toby J. Blundell Charles C. Agosta |
| author_sort | Brett Laramee |
| collection | DOAJ |
| description | We report rf-penetration depth measurements of the quasi-2D organic superconductor <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msup><mi>β</mi><mo>″</mo></msup></mrow></semantics></math></inline-formula>-(BEDT-TTF)<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msub><mrow></mrow><mn>2</mn></msub></semantics></math></inline-formula>[(H<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msub><mrow></mrow><mn>2</mn></msub></semantics></math></inline-formula>O)(NH<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msub><mrow></mrow><mn>4</mn></msub></semantics></math></inline-formula>)<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msub><mrow></mrow><mn>2</mn></msub></semantics></math></inline-formula>Cr(C<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msub><mrow></mrow><mn>2</mn></msub></semantics></math></inline-formula>O<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msub><mrow></mrow><mn>4</mn></msub></semantics></math></inline-formula>)<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msub><mrow></mrow><mn>3</mn></msub></semantics></math></inline-formula>]·18-crown-6, which has the largest separation between consecutive conduction layers of any 2D organic metal with a single packing motif. Using a contactless tunnel diode oscillator measurement technique, we show the zero-field cooling dependence and field sweeps up to 28 T oriented at various angles with respect to the crystal conduction planes. When oriented parallel to the layers, the upper critical field, <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msub><mi>H</mi><mrow><mi mathvariant="normal">c</mi><mn>2</mn></mrow></msub><mo>=</mo><mn>7.6</mn></mrow></semantics></math></inline-formula> T, which is the calculated paramagnetic limit for this material. No signs of inhomogeneous superconductivity are seen, despite previous predictions. When oriented perpendicular to the layers, Shubnikov–de Haas oscillations are seen as low as 6 T, and from these we calculate Fermi surface parameters such as the superconducting coherence length and Dingle temperature. One remarkable result from our data is the high anisotropy of <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msub><mi>H</mi><mrow><mi mathvariant="normal">c</mi><mn>2</mn></mrow></msub></semantics></math></inline-formula> in the parallel and perpendicular directions, due to an abnormally low <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msub><mi>H</mi><mrow><mi mathvariant="normal">c</mi><mn>2</mn><mo>⊥</mo></mrow></msub><mo>=</mo><mn>0.4</mn></mrow></semantics></math></inline-formula> T. Such high anisotropy is rare in other organics and the origin of the smaller <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msub><mi>H</mi><mrow><mi mathvariant="normal">c</mi><mn>2</mn><mo>⊥</mo></mrow></msub></semantics></math></inline-formula> may be a consequence of a lower effective mass. |
| first_indexed | 2024-03-11T06:16:22Z |
| format | Article |
| id | doaj.art-8017a176e7884897b6884831ed71dc4f |
| institution | Directory Open Access Journal |
| issn | 2312-7481 |
| language | English |
| last_indexed | 2024-03-11T06:16:22Z |
| publishDate | 2023-02-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Magnetochemistry |
| spelling | doaj.art-8017a176e7884897b6884831ed71dc4f2023-11-17T12:16:24ZengMDPI AGMagnetochemistry2312-74812023-02-01936410.3390/magnetochemistry9030064Superconductivity and Fermi Surface Studies of <i>β</i><sup>″</sup>-(BEDT-TTF)<sub>2</sub>[(H<sub>2</sub>O)(NH<sub>4</sub>)<sub>2</sub>Cr(C<sub>2</sub>O<sub>4</sub>)<sub>3</sub>]·18-Crown-6Brett Laramee0Raju Ghimire1David Graf2Lee Martin3Toby J. Blundell4Charles C. Agosta5Department of Physics, Clark University, Worcester, MA 01610, USADepartment of Physics, Clark University, Worcester, MA 01610, USANational High Magnetic Field Lab, Tallahassee, FL 32310-3706, USASchool of Science and Technology, Nottingham Trent University, Nottingham NG11 8NS, UKSchool of Science and Technology, Nottingham Trent University, Nottingham NG11 8NS, UKDepartment of Physics, Clark University, Worcester, MA 01610, USAWe report rf-penetration depth measurements of the quasi-2D organic superconductor <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msup><mi>β</mi><mo>″</mo></msup></mrow></semantics></math></inline-formula>-(BEDT-TTF)<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msub><mrow></mrow><mn>2</mn></msub></semantics></math></inline-formula>[(H<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msub><mrow></mrow><mn>2</mn></msub></semantics></math></inline-formula>O)(NH<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msub><mrow></mrow><mn>4</mn></msub></semantics></math></inline-formula>)<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msub><mrow></mrow><mn>2</mn></msub></semantics></math></inline-formula>Cr(C<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msub><mrow></mrow><mn>2</mn></msub></semantics></math></inline-formula>O<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msub><mrow></mrow><mn>4</mn></msub></semantics></math></inline-formula>)<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msub><mrow></mrow><mn>3</mn></msub></semantics></math></inline-formula>]·18-crown-6, which has the largest separation between consecutive conduction layers of any 2D organic metal with a single packing motif. Using a contactless tunnel diode oscillator measurement technique, we show the zero-field cooling dependence and field sweeps up to 28 T oriented at various angles with respect to the crystal conduction planes. When oriented parallel to the layers, the upper critical field, <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msub><mi>H</mi><mrow><mi mathvariant="normal">c</mi><mn>2</mn></mrow></msub><mo>=</mo><mn>7.6</mn></mrow></semantics></math></inline-formula> T, which is the calculated paramagnetic limit for this material. No signs of inhomogeneous superconductivity are seen, despite previous predictions. When oriented perpendicular to the layers, Shubnikov–de Haas oscillations are seen as low as 6 T, and from these we calculate Fermi surface parameters such as the superconducting coherence length and Dingle temperature. One remarkable result from our data is the high anisotropy of <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msub><mi>H</mi><mrow><mi mathvariant="normal">c</mi><mn>2</mn></mrow></msub></semantics></math></inline-formula> in the parallel and perpendicular directions, due to an abnormally low <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><msub><mi>H</mi><mrow><mi mathvariant="normal">c</mi><mn>2</mn><mo>⊥</mo></mrow></msub><mo>=</mo><mn>0.4</mn></mrow></semantics></math></inline-formula> T. Such high anisotropy is rare in other organics and the origin of the smaller <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msub><mi>H</mi><mrow><mi mathvariant="normal">c</mi><mn>2</mn><mo>⊥</mo></mrow></msub></semantics></math></inline-formula> may be a consequence of a lower effective mass.https://www.mdpi.com/2312-7481/9/3/64organic conductors2D metalsanisotropic superconductivity |
| spellingShingle | Brett Laramee Raju Ghimire David Graf Lee Martin Toby J. Blundell Charles C. Agosta Superconductivity and Fermi Surface Studies of <i>β</i><sup>″</sup>-(BEDT-TTF)<sub>2</sub>[(H<sub>2</sub>O)(NH<sub>4</sub>)<sub>2</sub>Cr(C<sub>2</sub>O<sub>4</sub>)<sub>3</sub>]·18-Crown-6 Magnetochemistry organic conductors 2D metals anisotropic superconductivity |
| title | Superconductivity and Fermi Surface Studies of <i>β</i><sup>″</sup>-(BEDT-TTF)<sub>2</sub>[(H<sub>2</sub>O)(NH<sub>4</sub>)<sub>2</sub>Cr(C<sub>2</sub>O<sub>4</sub>)<sub>3</sub>]·18-Crown-6 |
| title_full | Superconductivity and Fermi Surface Studies of <i>β</i><sup>″</sup>-(BEDT-TTF)<sub>2</sub>[(H<sub>2</sub>O)(NH<sub>4</sub>)<sub>2</sub>Cr(C<sub>2</sub>O<sub>4</sub>)<sub>3</sub>]·18-Crown-6 |
| title_fullStr | Superconductivity and Fermi Surface Studies of <i>β</i><sup>″</sup>-(BEDT-TTF)<sub>2</sub>[(H<sub>2</sub>O)(NH<sub>4</sub>)<sub>2</sub>Cr(C<sub>2</sub>O<sub>4</sub>)<sub>3</sub>]·18-Crown-6 |
| title_full_unstemmed | Superconductivity and Fermi Surface Studies of <i>β</i><sup>″</sup>-(BEDT-TTF)<sub>2</sub>[(H<sub>2</sub>O)(NH<sub>4</sub>)<sub>2</sub>Cr(C<sub>2</sub>O<sub>4</sub>)<sub>3</sub>]·18-Crown-6 |
| title_short | Superconductivity and Fermi Surface Studies of <i>β</i><sup>″</sup>-(BEDT-TTF)<sub>2</sub>[(H<sub>2</sub>O)(NH<sub>4</sub>)<sub>2</sub>Cr(C<sub>2</sub>O<sub>4</sub>)<sub>3</sub>]·18-Crown-6 |
| title_sort | superconductivity and fermi surface studies of i β i sup sup bedt ttf sub 2 sub h sub 2 sub o nh sub 4 sub sub 2 sub cr c sub 2 sub o sub 4 sub sub 3 sub ·18 crown 6 |
| topic | organic conductors 2D metals anisotropic superconductivity |
| url | https://www.mdpi.com/2312-7481/9/3/64 |
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