Bipartite Fluctuations of Critical Fermi Surfaces
Fuente:
arXiv
Saved in:
| Main Author: | |
|---|---|
| Format: | Preprint |
| Published: |
2024
|
| Subjects: | |
| Online Access: | |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1866913979378434048 |
|---|---|
| author | Wu, Xiao-Chuan |
| author_facet | Wu, Xiao-Chuan |
| contents | Fluctuations of conserved quantities within a subsystem are non-local observables that provide unique insights into quantum many-body systems. In this paper, we study bipartite charge (and spin) fluctuations across interaction-driven ``metal-insulator transitions'' out of Landau Fermi liquids. The ``charge insulators'' include a class of non-Fermi-liquid states of fractionalized degrees of freedom, such as compressible composite Fermi liquids (for spinless electrons) and incompressible spin-liquid Mott insulators (for spin-$1/2$ electrons). We find that charge fluctuations $F$ exhibit distinct leading-order scalings across the transition: $F \sim L\log(L)$ in Landau Fermi liquids and $F \sim L$ in charge insulators, where $L$ is the linear size of the subsystem. In composite Fermi liquids, under certain conditions, we also identify a universal constant term $-f(θ)|σ_{xy}|/(2π)$ when the subsystem geometry contains a sharp corner, where $f(θ)$ denotes a function of the corner angle, and $σ_{xy}$ is the Hall conductivity. At the critical point, provided the transition is continuous, the leading scaling $F\sim L$ is accompanied by a subleading universal corner contribution $-\log(L)f(θ)C_ρ/2$ with the same angle dependence $f(θ)$, and the universal coefficient $C_ρ$ is directly related to the predicted universal jumps in longitudinal and Hall resistivities. These results establish fluctuation-transport relations, paving the way for numerical and experimental studies of unconventional quantum criticalities in metals. |
| format | Preprint |
| id |
arxiv_https___arxiv_org_abs_2404_04331 |
| institution | arXiv |
| publishDate | 2024 |
| record_format | arxiv |
| spellingShingle | Bipartite Fluctuations of Critical Fermi Surfaces Wu, Xiao-Chuan Strongly Correlated Electrons Statistical Mechanics High Energy Physics - Theory Fluctuations of conserved quantities within a subsystem are non-local observables that provide unique insights into quantum many-body systems. In this paper, we study bipartite charge (and spin) fluctuations across interaction-driven ``metal-insulator transitions'' out of Landau Fermi liquids. The ``charge insulators'' include a class of non-Fermi-liquid states of fractionalized degrees of freedom, such as compressible composite Fermi liquids (for spinless electrons) and incompressible spin-liquid Mott insulators (for spin-$1/2$ electrons). We find that charge fluctuations $F$ exhibit distinct leading-order scalings across the transition: $F \sim L\log(L)$ in Landau Fermi liquids and $F \sim L$ in charge insulators, where $L$ is the linear size of the subsystem. In composite Fermi liquids, under certain conditions, we also identify a universal constant term $-f(θ)|σ_{xy}|/(2π)$ when the subsystem geometry contains a sharp corner, where $f(θ)$ denotes a function of the corner angle, and $σ_{xy}$ is the Hall conductivity. At the critical point, provided the transition is continuous, the leading scaling $F\sim L$ is accompanied by a subleading universal corner contribution $-\log(L)f(θ)C_ρ/2$ with the same angle dependence $f(θ)$, and the universal coefficient $C_ρ$ is directly related to the predicted universal jumps in longitudinal and Hall resistivities. These results establish fluctuation-transport relations, paving the way for numerical and experimental studies of unconventional quantum criticalities in metals. |
| title | Bipartite Fluctuations of Critical Fermi Surfaces |
| topic | Strongly Correlated Electrons Statistical Mechanics High Energy Physics - Theory |
| url | https://arxiv.org/abs/2404.04331 |