Antiferromagnetic Magnons from Fractionalized Excitations
ORAL
Abstract
We develop an approach to describe antiferromagnetic magnons on a bipartite lattice supporting
the Neel state using fractionalized degrees of freedom typically inherent to quantum spin liquids.
In particular we consider a long-range magnetically ordered state of interacting two-dimensional
quantum spin 1/2 models using the Chern-Simons (CS) fermion representation of interacting spins.
The interaction leads to Cooper instability and pairing of CS fermions, and to CS superconductivity
which spontaneously violates the continuous U(1) symmetry generating a linearly-dispersing gapless
Nambu-Goldstone mode due to phase fluctuations. We evaluate this mode and show that it is in
high-precision agreement with magnons of the corresponding Neel antiferromagnet irrespective to
the lattice symmetry.
the Neel state using fractionalized degrees of freedom typically inherent to quantum spin liquids.
In particular we consider a long-range magnetically ordered state of interacting two-dimensional
quantum spin 1/2 models using the Chern-Simons (CS) fermion representation of interacting spins.
The interaction leads to Cooper instability and pairing of CS fermions, and to CS superconductivity
which spontaneously violates the continuous U(1) symmetry generating a linearly-dispersing gapless
Nambu-Goldstone mode due to phase fluctuations. We evaluate this mode and show that it is in
high-precision agreement with magnons of the corresponding Neel antiferromagnet irrespective to
the lattice symmetry.
*This work was supported by the National Key R&D Program of China (Grant No. 2017YFA0303200),
and by NSFC under Grants No. 11574217 and No. 60825402. T.A.S. acknowledges startup funds
from UMass Amherst.
–
Presenters
-
Rui Wang
- Department of Physics and Astronomy, Shanghai Jiao Tong University
- Nanjing Univ
- Shanghai Jiao Tong University