Transverse Spin Dynamics in the Anisotropic Heisenberg Model Realized with Ultracold Atoms
In Heisenberg models with exchange anisotropy, transverse spin components are not conserved and can decay not only by transport, but also by dephasing. Here, we utilize ultracold atoms to simulate the dynamics of 1D Heisenberg spin chains and observe fast, local spin decay controlled by the anisotro...
| Main Authors: | , , , , , |
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| Format: | Article |
| Language: | English |
| Published: |
American Physical Society
2021-12-01
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| Series: | Physical Review X |
| Online Access: | http://doi.org/10.1103/PhysRevX.11.041054 |
| _version_ | 1831758703421816832 |
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| author | Paul Niklas Jepsen Wen Wei Ho Jesse Amato-Grill Ivana Dimitrova Eugene Demler Wolfgang Ketterle |
| author_facet | Paul Niklas Jepsen Wen Wei Ho Jesse Amato-Grill Ivana Dimitrova Eugene Demler Wolfgang Ketterle |
| author_sort | Paul Niklas Jepsen |
| collection | DOAJ |
| description | In Heisenberg models with exchange anisotropy, transverse spin components are not conserved and can decay not only by transport, but also by dephasing. Here, we utilize ultracold atoms to simulate the dynamics of 1D Heisenberg spin chains and observe fast, local spin decay controlled by the anisotropy. However, even for isotropic interactions, we observe dephasing due to a new effect: an effective magnetic field created by superexchange. If spatially uniform, it leads only to uniform spin precession and is, therefore, typically ignored. However, we show through experimental studies and extensive numerical simulations how this superexchange-generated field is relevant and leads to additional dephasing mechanisms over the exchange anisotropy: There is dephasing due to (i) inhomogeneity of the effective field from variations of lattice depth between chains; (ii) a twofold reduction of the field at the edges of finite chains; and (iii) fluctuations of the effective field due to the presence of mobile holes in the system. The latter is a new coupling mechanism between holes and magnons. All these dephasing mechanisms have not been observed before with ultracold atoms and illustrate basic properties of the underlying Hubbard model. |
| first_indexed | 2024-12-22T00:53:15Z |
| format | Article |
| id | doaj.art-8b298fa4eb1b4b6cb571dd669f7ef52d |
| institution | Directory Open Access Journal |
| issn | 2160-3308 |
| language | English |
| last_indexed | 2024-12-22T00:53:15Z |
| publishDate | 2021-12-01 |
| publisher | American Physical Society |
| record_format | Article |
| series | Physical Review X |
| spelling | doaj.art-8b298fa4eb1b4b6cb571dd669f7ef52d2022-12-21T18:44:22ZengAmerican Physical SocietyPhysical Review X2160-33082021-12-0111404105410.1103/PhysRevX.11.041054Transverse Spin Dynamics in the Anisotropic Heisenberg Model Realized with Ultracold AtomsPaul Niklas JepsenWen Wei HoJesse Amato-GrillIvana DimitrovaEugene DemlerWolfgang KetterleIn Heisenberg models with exchange anisotropy, transverse spin components are not conserved and can decay not only by transport, but also by dephasing. Here, we utilize ultracold atoms to simulate the dynamics of 1D Heisenberg spin chains and observe fast, local spin decay controlled by the anisotropy. However, even for isotropic interactions, we observe dephasing due to a new effect: an effective magnetic field created by superexchange. If spatially uniform, it leads only to uniform spin precession and is, therefore, typically ignored. However, we show through experimental studies and extensive numerical simulations how this superexchange-generated field is relevant and leads to additional dephasing mechanisms over the exchange anisotropy: There is dephasing due to (i) inhomogeneity of the effective field from variations of lattice depth between chains; (ii) a twofold reduction of the field at the edges of finite chains; and (iii) fluctuations of the effective field due to the presence of mobile holes in the system. The latter is a new coupling mechanism between holes and magnons. All these dephasing mechanisms have not been observed before with ultracold atoms and illustrate basic properties of the underlying Hubbard model.http://doi.org/10.1103/PhysRevX.11.041054 |
| spellingShingle | Paul Niklas Jepsen Wen Wei Ho Jesse Amato-Grill Ivana Dimitrova Eugene Demler Wolfgang Ketterle Transverse Spin Dynamics in the Anisotropic Heisenberg Model Realized with Ultracold Atoms Physical Review X |
| title | Transverse Spin Dynamics in the Anisotropic Heisenberg Model Realized with Ultracold Atoms |
| title_full | Transverse Spin Dynamics in the Anisotropic Heisenberg Model Realized with Ultracold Atoms |
| title_fullStr | Transverse Spin Dynamics in the Anisotropic Heisenberg Model Realized with Ultracold Atoms |
| title_full_unstemmed | Transverse Spin Dynamics in the Anisotropic Heisenberg Model Realized with Ultracold Atoms |
| title_short | Transverse Spin Dynamics in the Anisotropic Heisenberg Model Realized with Ultracold Atoms |
| title_sort | transverse spin dynamics in the anisotropic heisenberg model realized with ultracold atoms |
| url | http://doi.org/10.1103/PhysRevX.11.041054 |
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