Quantum criticality and non-Fermi liquids: the nonperturbative renormalization group perspective
Fuente:
arXiv
Enregistré dans:
| Auteurs principaux: | , , |
|---|---|
| Format: | Preprint |
| Publié: |
2025
|
| Sujets: | |
| Accès en ligne: | |
| Tags: |
Ajouter un tag
Pas de tags, Soyez le premier à ajouter un tag!
|
| _version_ | 1866908364695404544 |
|---|---|
| author | Homenda, Mateusz Jakubczyk, Pawel Yamase, Hiroyuki |
| author_facet | Homenda, Mateusz Jakubczyk, Pawel Yamase, Hiroyuki |
| contents | We develop a thorough theoretical framework based on the nonperturvative renormalization group (RG) a la Wetterich to tackle the interplay of coupled fermionic and order-parameter fluctuations at metallic quantum critical points with ordering wavevectors $\vec{Q}=\vec{0}$. We consistently treat the dynamical emergence of the Landau damping of the bosonic mode and non-Fermi liquid scaling of fermions upon lowering the cutoff scale. The loop integrals of the present theory involve only contributions from fluctuations above the cutoff scale, which drive the system to a non-Fermi liquid RG fixed point of different scaling properties from those obtained within the random phase approximation (RPA) or expansions around it. In particular the scaling exponent for the Fermi self-energy acquires the value $α\approx 0.50$ rather than the anticipated $α\approx 0.66$, while the bosonic dynamical exponent $z\approx 2$. We demonstrate how results characteristic for the RPA-type fixed-point scaling are recovered in our framework by a questionable procedure of removing the fermionic cutoff much faster than the bosonic one. |
| format | Preprint |
| id |
arxiv_https___arxiv_org_abs_2505_10140 |
| institution | arXiv |
| publishDate | 2025 |
| record_format | arxiv |
| spellingShingle | Quantum criticality and non-Fermi liquids: the nonperturbative renormalization group perspective Homenda, Mateusz Jakubczyk, Pawel Yamase, Hiroyuki Strongly Correlated Electrons High Energy Physics - Theory We develop a thorough theoretical framework based on the nonperturvative renormalization group (RG) a la Wetterich to tackle the interplay of coupled fermionic and order-parameter fluctuations at metallic quantum critical points with ordering wavevectors $\vec{Q}=\vec{0}$. We consistently treat the dynamical emergence of the Landau damping of the bosonic mode and non-Fermi liquid scaling of fermions upon lowering the cutoff scale. The loop integrals of the present theory involve only contributions from fluctuations above the cutoff scale, which drive the system to a non-Fermi liquid RG fixed point of different scaling properties from those obtained within the random phase approximation (RPA) or expansions around it. In particular the scaling exponent for the Fermi self-energy acquires the value $α\approx 0.50$ rather than the anticipated $α\approx 0.66$, while the bosonic dynamical exponent $z\approx 2$. We demonstrate how results characteristic for the RPA-type fixed-point scaling are recovered in our framework by a questionable procedure of removing the fermionic cutoff much faster than the bosonic one. |
| title | Quantum criticality and non-Fermi liquids: the nonperturbative renormalization group perspective |
| topic | Strongly Correlated Electrons High Energy Physics - Theory |
| url | https://arxiv.org/abs/2505.10140 |