Quantum Entangled Fractional Topology and Curvatures
International audience We propose a two-spin quantum-mechanical model with applied magnetic fields acting on the Poincaré-Bloch sphere, to reveal a new class of topological energy bands with Chern number one half for each spin-1/2. The mechanism behind this fractional topology is a two-spin product...
| Published in: | Communications Physics |
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| Main Authors: | , |
| Other Authors: | , |
| Format: | Article in Journal/Newspaper |
| Language: | English |
| Published: |
HAL CCSD
2021
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| Subjects: | |
| Online Access: | https://hal.science/hal-02507659 https://doi.org/10.1038/s42005-021-00641-0 |
| Summary: | International audience We propose a two-spin quantum-mechanical model with applied magnetic fields acting on the Poincaré-Bloch sphere, to reveal a new class of topological energy bands with Chern number one half for each spin-1/2. The mechanism behind this fractional topology is a two-spin product state at the north pole and a maximally entangled state close to the south pole. The fractional Chern number of each spin can be measured through the magnetizations at the poles. We study a precise protocol where the spin dynamics in time reflects the Landau-Zener physics associated with energy band crossing effects. We show a correspondence between the two-spin system and topological bilayer models on a honeycomb lattice. These models describe semimetals with a nodal ring surrounding the region of entanglement. |
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