首页|Quasi-2D spin-Peierls transition through interstitial anionic electrons in K(NH3)2

Quasi-2D spin-Peierls transition through interstitial anionic electrons in K(NH3)2

扫码查看
原文链接
  • NETL
  • NSTL
  • 万方数据
Electron-phonon interactions and electron-electron correlations represent two crucial facets of condensed matter physics.For instance,in a half-filled spin-1/2 anti-ferromagnetic chain,the lattice dimerization induced by electron-nucleus interaction can be intensified by onsite Coulomb repulsion,resulting in a spin-Peierls state.Through first-principles calculations and crystal structure prediction methods,we have identified that under mild pressures,potassium and ammonia can form stable compounds:R3m K(NH3)2,Pm3m K(NH3)2,and Cm K2(NH3)3.Our predictions suggest that the R3 m K(NH3)2 exhibits electride characteristics,marked by the formation of interstitial anionic electrons(IAEs)in the interlayer space.These IAEs are arranged in quasi-two-dimensional triangular arrays.With increasing pressure,the electronic van-Hove singularity shifts toward the Fermi level,resulting in an augmented density of states and the onset of both Peierls and magnetic instabilities.Analyzing these instabilities,we determine that the ground state of the R3 m K(NH3)2 is the dimerized P2i/m phase with zigzag-type anti-ferromagnetic IAEs.This state can be described by the triangular-lattice antiferromag-netic Heisenberg model with modulated magnetic interactions.Furthermore,we unveil the coexistence and positive interplay between magnetic and Peierls instability,constituting a scenario of spin-Peierls instability unprecedented in realistic 2D materials,particularly involving IAEs.This work provides valuable insights into the coupling of IAEs with the adjacent lattice and their spin correlations in quantum materials.

Quasi-two-dimensionalInterstitial anionic electronsPotassium ammonia compoundsSpin-Peierls transitionAntiferromagnetism

Chi Ding、Qing Lu、Zhaopeng Guo、Tianheng Huang、Junjie Wang、Yu Han、Dingyu Xing、Jian Sun

展开 >

National Laboratory of Solid State Microstructures,School of Physics and Collaborative Innovation Center of Advanced Microstructures,Nanjing University,Nanjing 210093,China

National Key R&D Program of ChinaNational Natural Science Foundation of ChinaNational Natural Science Foundation of ChinaNational Natural Science Foundation of ChinaFundamental Research Funds for the Central UniversitiesHigh-Performance Computing Center of Collaborative Innovation Center of Advanced Microstructures,the highperformance superco

2022YFA1403201121254041197416211834006

2024

10.1016/j.scib.2024.02.016

科学通报(英文版)
中国科学院

科学通报(英文版)

CSTPCD
ISSN：1001-6538
年,卷(期)：2024.69(8)
  • 54