Conductance asymmetries in mesoscopic superconducting devices due to finite bias
Tunneling conductance spectroscopy in normal metal-superconductor junctions is an important tool for probing Andreev bound states in mesoscopic superconducting devices, such as Majorana nanowires. In an ideal superconducting device, the subgap conductance obeys specific symmetry relations, due t...
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| Format: | Article |
| Language: | English |
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SciPost
2021-02-01
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| Series: | SciPost Physics |
| Online Access: | https://scipost.org/SciPostPhys.10.2.037 |
| _version_ | 1818956066526855168 |
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| author | André Melo, Chun-Xiao Liu, Piotr Rożek, Tómas Örn Rosdahl, Michael Wimmer |
| author_facet | André Melo, Chun-Xiao Liu, Piotr Rożek, Tómas Örn Rosdahl, Michael Wimmer |
| author_sort | André Melo, Chun-Xiao Liu, Piotr Rożek, Tómas Örn Rosdahl, Michael Wimmer |
| collection | DOAJ |
| description | Tunneling conductance spectroscopy in normal metal-superconductor junctions
is an important tool for probing Andreev bound states in mesoscopic
superconducting devices, such as Majorana nanowires. In an ideal
superconducting device, the subgap conductance obeys specific symmetry
relations, due to particle-hole symmetry and unitarity of the scattering
matrix. However, experimental data often exhibits deviations from these
symmetries or even their explicit breakdown. In this work, we identify a
mechanism that leads to conductance asymmetries without quasiparticle
poisoning. In particular, we investigate the effects of finite bias and include
the voltage dependence in the tunnel barrier transparency, finding significant
conductance asymmetries for realistic device parameters. It is important to
identify the physical origin of conductance asymmetries: in contrast to other
possible mechanisms such as quasiparticle poisoning, finite-bias effects are
not detrimental to the performance of a topological qubit. To that end we
identify features that can be used to experimentally determine whether
finite-bias effects are the source of conductance asymmetries. |
| first_indexed | 2024-12-20T10:48:03Z |
| format | Article |
| id | doaj.art-0211966cf6e24ad98e9e08d78c21d981 |
| institution | Directory Open Access Journal |
| issn | 2542-4653 |
| language | English |
| last_indexed | 2024-12-20T10:48:03Z |
| publishDate | 2021-02-01 |
| publisher | SciPost |
| record_format | Article |
| series | SciPost Physics |
| spelling | doaj.art-0211966cf6e24ad98e9e08d78c21d9812022-12-21T19:43:20ZengSciPostSciPost Physics2542-46532021-02-0110203710.21468/SciPostPhys.10.2.037Conductance asymmetries in mesoscopic superconducting devices due to finite biasAndré Melo, Chun-Xiao Liu, Piotr Rożek, Tómas Örn Rosdahl, Michael WimmerTunneling conductance spectroscopy in normal metal-superconductor junctions is an important tool for probing Andreev bound states in mesoscopic superconducting devices, such as Majorana nanowires. In an ideal superconducting device, the subgap conductance obeys specific symmetry relations, due to particle-hole symmetry and unitarity of the scattering matrix. However, experimental data often exhibits deviations from these symmetries or even their explicit breakdown. In this work, we identify a mechanism that leads to conductance asymmetries without quasiparticle poisoning. In particular, we investigate the effects of finite bias and include the voltage dependence in the tunnel barrier transparency, finding significant conductance asymmetries for realistic device parameters. It is important to identify the physical origin of conductance asymmetries: in contrast to other possible mechanisms such as quasiparticle poisoning, finite-bias effects are not detrimental to the performance of a topological qubit. To that end we identify features that can be used to experimentally determine whether finite-bias effects are the source of conductance asymmetries.https://scipost.org/SciPostPhys.10.2.037 |
| spellingShingle | André Melo, Chun-Xiao Liu, Piotr Rożek, Tómas Örn Rosdahl, Michael Wimmer Conductance asymmetries in mesoscopic superconducting devices due to finite bias SciPost Physics |
| title | Conductance asymmetries in mesoscopic superconducting devices due to finite bias |
| title_full | Conductance asymmetries in mesoscopic superconducting devices due to finite bias |
| title_fullStr | Conductance asymmetries in mesoscopic superconducting devices due to finite bias |
| title_full_unstemmed | Conductance asymmetries in mesoscopic superconducting devices due to finite bias |
| title_short | Conductance asymmetries in mesoscopic superconducting devices due to finite bias |
| title_sort | conductance asymmetries in mesoscopic superconducting devices due to finite bias |
| url | https://scipost.org/SciPostPhys.10.2.037 |
| work_keys_str_mv | AT andremelochunxiaoliupiotrrozektomasornrosdahlmichaelwimmer conductanceasymmetriesinmesoscopicsuperconductingdevicesduetofinitebias |