Skip to content

Probing loop currents and collective modes of charge density waves in Kagome materials with NV centers

MetadataDetails
Publication Date2025-06-20
Journalnpj Quantum Materials
AuthorsYing-Ming Xie, Naoto Nagaosa
AnalysisFull AI Review Included

Okay, I’ll analyze the research paper and provide the requested sections in Markdown format, adhering to the specified formatting rules.

  • Investigates collective modes of charge density waves (CDWs) in Kagome materials, specifically AV3Sb5 (A = K, Rb, Cs), focusing on loop current order.
  • Analyzes both real CDW (rCDW) and imaginary CDW (iCDW) order parameters using a mean-field free energy approach.
  • Identifies a key distinction: phase and amplitude modes mix in iCDW, while they remain decoupled in rCDW.
  • Proposes using nitrogen-vacancy (NV) centers to detect time-dependent stray fields generated by phase mode excitations in iCDW, offering a potential experimental probe for loop current order.
  • The proposed method leverages the sensitivity of NV centers to magnetic noise arising from loop current fluctuations.
  • Provides a theoretical framework for understanding collective excitations in iCDW and their connection to experimentally measurable quantities.

| Parameter | Value THE NV CENTER IS USED TO DETECT THE MAGNETIC FIELD.

View Original Abstract

Abstract Recently, the unconventional charge density wave (CDW) order with loop currents has attracted considerable attention in the Kagome material family AV3Sb5 (A = K, Rb, Cs). However, experimental signatures of loop current order remain elusive. In this work, based on the mean-field free energy, we analyze the collective modes of unconventional CDW order in a Kagome lattice model. Furthermore, we point out that phase modes in the imaginary CDW (iCDW) order with loop current orders result in time-dependent stray fields. We thus propose using nitrogen-vacancy (NV) centers to detect these time-dependent stray fields, providing a potential experimental approach to identifying loop current order.