Electron Pumping and Spectral Density Dynamics in Energy-Gapped Topological Chains
Electron pumping through energy-gapped systems is restricted for vanishing local density of states at the Fermi level. In this paper, we propose a topological Su–Schrieffer–Heeger (SSH) chain between unbiased leads as an effective electron pump. We analyze the electron transport properties of topolo...
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| Format: | Article |
| Language: | English |
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MDPI AG
2021-01-01
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| Series: | Applied Sciences |
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| Online Access: | https://www.mdpi.com/2076-3417/11/2/772 |
| _version_ | 1797411277877805056 |
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| author | Marcin Kurzyna Tomasz Kwapiński |
| author_facet | Marcin Kurzyna Tomasz Kwapiński |
| author_sort | Marcin Kurzyna |
| collection | DOAJ |
| description | Electron pumping through energy-gapped systems is restricted for vanishing local density of states at the Fermi level. In this paper, we propose a topological Su–Schrieffer–Heeger (SSH) chain between unbiased leads as an effective electron pump. We analyze the electron transport properties of topologically trivial and nontrivial systems in the presence of external time-dependent forces in the form of one-Gaussian or two-Gaussian perturbations (train impulses). We have found that the topologically trivial chain stands for much better charge pump than other normal or nontrivial chains. It is important that, during the perturbation, electrons are pumped through the mid-gap temporary states or through the induced sidebands states outside the energy gap. We also analyze the local density of states dynamics during the quench transition between different topological phases of the SSH chain. It turns out that after the quench, the edge topological states migrate through other sites and can temporarily exist in a topologically trivial part of the system. The tight-binding Hamiltonian and the evolution operator technique are used in our calculations. |
| first_indexed | 2024-03-09T04:42:46Z |
| format | Article |
| id | doaj.art-3327da554fb9473891cd0206809199fe |
| institution | Directory Open Access Journal |
| issn | 2076-3417 |
| language | English |
| last_indexed | 2024-03-09T04:42:46Z |
| publishDate | 2021-01-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Applied Sciences |
| spelling | doaj.art-3327da554fb9473891cd0206809199fe2023-12-03T13:18:51ZengMDPI AGApplied Sciences2076-34172021-01-0111277210.3390/app11020772Electron Pumping and Spectral Density Dynamics in Energy-Gapped Topological ChainsMarcin Kurzyna0Tomasz Kwapiński1Department of Physics, Maria Curie-Sklodowska University, PL20031 Lublin, PolandDepartment of Physics, Maria Curie-Sklodowska University, PL20031 Lublin, PolandElectron pumping through energy-gapped systems is restricted for vanishing local density of states at the Fermi level. In this paper, we propose a topological Su–Schrieffer–Heeger (SSH) chain between unbiased leads as an effective electron pump. We analyze the electron transport properties of topologically trivial and nontrivial systems in the presence of external time-dependent forces in the form of one-Gaussian or two-Gaussian perturbations (train impulses). We have found that the topologically trivial chain stands for much better charge pump than other normal or nontrivial chains. It is important that, during the perturbation, electrons are pumped through the mid-gap temporary states or through the induced sidebands states outside the energy gap. We also analyze the local density of states dynamics during the quench transition between different topological phases of the SSH chain. It turns out that after the quench, the edge topological states migrate through other sites and can temporarily exist in a topologically trivial part of the system. The tight-binding Hamiltonian and the evolution operator technique are used in our calculations.https://www.mdpi.com/2076-3417/11/2/772quantum dotscharge pumpingtopologyatomic chains |
| spellingShingle | Marcin Kurzyna Tomasz Kwapiński Electron Pumping and Spectral Density Dynamics in Energy-Gapped Topological Chains Applied Sciences quantum dots charge pumping topology atomic chains |
| title | Electron Pumping and Spectral Density Dynamics in Energy-Gapped Topological Chains |
| title_full | Electron Pumping and Spectral Density Dynamics in Energy-Gapped Topological Chains |
| title_fullStr | Electron Pumping and Spectral Density Dynamics in Energy-Gapped Topological Chains |
| title_full_unstemmed | Electron Pumping and Spectral Density Dynamics in Energy-Gapped Topological Chains |
| title_short | Electron Pumping and Spectral Density Dynamics in Energy-Gapped Topological Chains |
| title_sort | electron pumping and spectral density dynamics in energy gapped topological chains |
| topic | quantum dots charge pumping topology atomic chains |
| url | https://www.mdpi.com/2076-3417/11/2/772 |
| work_keys_str_mv | AT marcinkurzyna electronpumpingandspectraldensitydynamicsinenergygappedtopologicalchains AT tomaszkwapinski electronpumpingandspectraldensitydynamicsinenergygappedtopologicalchains |