Witnessing disorder in quantum magnets
There are no clean samples in nature. Therefore, when we come to discuss the entanglement properties of quantum materials, the effects of disorder must be taken into account. This question is of particular interest for highly entangled phases, such as quantum spin liquids, which lie outside the Land...
Saved in:
| Main Authors: | , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
American Physical Society
2025-06-01
|
| Series: | Physical Review Research |
| Online Access: | http://doi.org/10.1103/95fl-rxl3 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1849334407187398656 |
|---|---|
| author | Snigdh Sabharwal Tokuro Shimokawa Nic Shannon |
| author_facet | Snigdh Sabharwal Tokuro Shimokawa Nic Shannon |
| author_sort | Snigdh Sabharwal |
| collection | DOAJ |
| description | There are no clean samples in nature. Therefore, when we come to discuss the entanglement properties of quantum materials, the effects of disorder must be taken into account. This question is of particular interest for highly entangled phases, such as quantum spin liquids, which lie outside the Landau paradigm for classifying phases of matter. In this work, we explore what experimentally accessible measures, in the form of concurrence, residual tangle, and quantum Fisher information can teach us about the entanglement in the presence of disorder. As a representative example, we consider the Tomonaga-Luttinger liquids (TLL) and disorder-driven random singlet (RS) phases found in antiferromagnetic quantum spin chains. Using quantum Fisher information and residual tangle, we demonstrate that both TLL and RS phases exhibit multipartite entanglement. In the case of the RS phase, we attribute this to entanglement localized below a crossover length scale. We further show that the order of disorder average matters in calculating measures like concurrence and that this can lead to false inferences when interpreting experiments. Nonetheless, correctly interpreted, these witnesses provide useful information about the effects of disorder. We explore how information about the central charge of the TLL can be extracted from the low-temperature behavior of concurrence and conjecture that this analysis can be extended to the effective central charge of the RS phase. Finally, we establish how RS and TLL phases can be distinguished through the growth of multipartite entanglement, as witnessed by the equal-time structure factor. These results establish that, used carefully, experiments based on entanglement witnesses can provide important information about quantum spin systems in the presence of disorder. |
| format | Article |
| id | doaj-art-4a135faa7df9400ab2ec85d527f03df5 |
| institution | Kabale University |
| issn | 2643-1564 |
| language | English |
| publishDate | 2025-06-01 |
| publisher | American Physical Society |
| record_format | Article |
| series | Physical Review Research |
| spelling | doaj-art-4a135faa7df9400ab2ec85d527f03df52025-08-20T03:45:35ZengAmerican Physical SocietyPhysical Review Research2643-15642025-06-017202327110.1103/95fl-rxl3Witnessing disorder in quantum magnetsSnigdh SabharwalTokuro ShimokawaNic ShannonThere are no clean samples in nature. Therefore, when we come to discuss the entanglement properties of quantum materials, the effects of disorder must be taken into account. This question is of particular interest for highly entangled phases, such as quantum spin liquids, which lie outside the Landau paradigm for classifying phases of matter. In this work, we explore what experimentally accessible measures, in the form of concurrence, residual tangle, and quantum Fisher information can teach us about the entanglement in the presence of disorder. As a representative example, we consider the Tomonaga-Luttinger liquids (TLL) and disorder-driven random singlet (RS) phases found in antiferromagnetic quantum spin chains. Using quantum Fisher information and residual tangle, we demonstrate that both TLL and RS phases exhibit multipartite entanglement. In the case of the RS phase, we attribute this to entanglement localized below a crossover length scale. We further show that the order of disorder average matters in calculating measures like concurrence and that this can lead to false inferences when interpreting experiments. Nonetheless, correctly interpreted, these witnesses provide useful information about the effects of disorder. We explore how information about the central charge of the TLL can be extracted from the low-temperature behavior of concurrence and conjecture that this analysis can be extended to the effective central charge of the RS phase. Finally, we establish how RS and TLL phases can be distinguished through the growth of multipartite entanglement, as witnessed by the equal-time structure factor. These results establish that, used carefully, experiments based on entanglement witnesses can provide important information about quantum spin systems in the presence of disorder.http://doi.org/10.1103/95fl-rxl3 |
| spellingShingle | Snigdh Sabharwal Tokuro Shimokawa Nic Shannon Witnessing disorder in quantum magnets Physical Review Research |
| title | Witnessing disorder in quantum magnets |
| title_full | Witnessing disorder in quantum magnets |
| title_fullStr | Witnessing disorder in quantum magnets |
| title_full_unstemmed | Witnessing disorder in quantum magnets |
| title_short | Witnessing disorder in quantum magnets |
| title_sort | witnessing disorder in quantum magnets |
| url | http://doi.org/10.1103/95fl-rxl3 |
| work_keys_str_mv | AT snigdhsabharwal witnessingdisorderinquantummagnets AT tokuroshimokawa witnessingdisorderinquantummagnets AT nicshannon witnessingdisorderinquantummagnets |