Search Results - "loop-current order"

Additional Titles: Emergence of quantum orders with nontrivial quantum geometric properties in metals represent central issues in condensed matter physics. In this context, recently discovered chiral loop-current order in kagome metals has garnered signiﬁcant attention. Particularly noteworthy is the giant electrical magnetochiral anisotropy (eMChA)observed in CsV₃Sb₅, which provides compelling evidence for the simultaneous breaking of time-reversal and inversion symmetries. However, the origin of the eMChA and its fundamental connection to the loop-current remain highly elusive, as the loop-current itself preserves inversion symmetry. Here, we demonstrate that the loop-current phase breaks inversion symmetry in the presence of the experimentally observed stripe charge-density wave, leading to finite eMChA coefficient γ[eM]. In this mechanism, γ[eM] is proportional to the product of the loop-current-induced orbital magnetization, M⁰[orb], and the lifetime of conduction electrons, τ. Therefore, γ[eM] is reversible by the magnetic ﬁelds, and it takes large value in kagome metals with τvFermi ≫ a₀ (=lattice constant). Surprisingly, the quantum metric, which defines a fundamental geometric aspect of Bloch wavefunctions, acquires signiﬁcant momentum dependence in the loop-current phase, resulting in a dramatic enhancement of eMChA by ∼100 times. This research not only clarifies the fundamental symmetry-breaking states in kagome metals but also opens a path for exploring quantum metric-induced phenomena arising from exotic quantum phase transitions in various metals.

Authors: Yamakawa, Youichi, Morimoto, Takahiro, Hiroshi Kontani, Tazai, Rina

Index Terms: kagome metals, loop-current order, electrical magnetochiral anisotropy (eMChA), quantum metric, Journal Article., VoR.

URL: http://hdl.handle.net/2433/296960
https://doi.org/10.1073/pnas.2503645122
https://repository.kulib.kyoto-u.ac.jp/bitstreams/97a26944-c397-4ebb-b407-ec5aed1ed790/download
40854118

View this record from OAIster

7

Academic Journal

Quantum metric-induced giant and reversible nonreciprocal transport phenomena in chiral loop-current phases of kagome metals.

Authors: Tazai R; Yukawa Institute for Theoretical Physics, Kyoto University, Kyoto 606-8502, Japan., Yamakawa Y; Department of Physics, Nagoya University, Furo-cho, Nagoya 464-8602, Japan., Morimoto T; Department of Applied Physics, The University of Tokyo, Hongo, Tokyo 113-8656, Japan., Kontani H; Department of Physics, Nagoya University, Furo-cho, Nagoya 464-8602, Japan.

Source: Proceedings of the National Academy of Sciences of the United States of America [Proc Natl Acad Sci U S A] 2025 Sep 02; Vol. 122 (35), pp. e2503645122. Date of Electronic Publication: 2025 Aug 25.

Publication Type: Journal Article

Journal Info: Publisher: National Academy of Sciences Country of Publication: United States NLM ID: 7505876 Publication Model: Print-Electronic Cited Medium: Internet ISSN: 1091-6490 (Electronic) Linking ISSN: 00278424 NLM ISO Abbreviation: Proc Natl Acad Sci U S A Subsets: MEDLINE; PubMed not MEDLINE

Full Text Finder

8

Mixed Materials

Drastic magnetic-field-induced chiral current order and emergent current-bond-field interplay in kagome metals

Additional Titles: In kagome metals, the chiral current order parameter η with time-reversal-symmetry-breaking is the source of various exotic electronic states, while the method of controlling the current order and its interplay with the star-of-David bond order φ are still unsolved. Here, we reveal that tiny uniform orbital magnetization Morb[η, φ] is induced by the chiral current order, and its magnitude is prominently enlarged under the presence of the bond order. Importantly, we derive the magnetic-ﬁeld (hz)-induced Ginzburg–Landau (GL) free energy expression ΔF[hz, η, φ] ∝ −hzMorb[η, φ], which enables us to elucidate the ﬁeld-induced current-bond phase transitions in kagomemetals. The emergent current-bond-hz trilinear coupling term in the free energy, −m₁hzη·φ, naturally explains the characteristic magnetic-ﬁeld sensitive electronic states in kagome metals, such as the ﬁeld-induced current order and the strong interplay between the bond and current orders. The GL coefﬁcients of ΔF[hz, η, φ] derived from the realistic multiorbital model are appropriate to explain various experiments. Furthermore, we discuss the ﬁeld-induced loop current orders in the square lattice models that have been studied in cuprate superconductors.

Authors: 10880023, Tazai, Rina, Yamakawa, Youichi, Kontani, Hiroshi

Index Terms: kagome metals, loop current order, bond order, Ginzburg–Landau theory, journal article

URL: http://hdl.handle.net/2433/299021
https://www.kyoto-u.ac.jp/ja/research-news/2024-01-17
10.1073/pnas.2303476121
https://www.kyoto-u.ac.jp/ja/research-news/2024-01-17

View this record from OAIster

9

Academic Journal

Drastic magnetic-field-induced chiral current order and emergent current-bond-field interplay in kagome metals.

Authors: Tazai R; Yukawa Institute for Theoretical Physics, Kyoto University, Kyoto 606-8502, Japan., Yamakawa Y; Department of Physics, Nagoya University, Nagoya 464-8602, Japan., Kontani H; Department of Physics, Nagoya University, Nagoya 464-8602, Japan.

Source: Proceedings of the National Academy of Sciences of the United States of America [Proc Natl Acad Sci U S A] 2024 Jan 16; Vol. 121 (3), pp. e2303476121. Date of Electronic Publication: 2024 Jan 11.

Publication Type: Journal Article

Journal Info: Publisher: National Academy of Sciences Country of Publication: United States NLM ID: 7505876 Publication Model: Print-Electronic Cited Medium: Internet ISSN: 1091-6490 (Electronic) Linking ISSN: 00278424 NLM ISO Abbreviation: Proc Natl Acad Sci U S A Subsets: MEDLINE; PubMed not MEDLINE

Full Text Finder

Search Tools:

Refine Results

Format

Subject

Publisher

Published in

Source

Collection

Year of Publication