Exotic gapless spectrum induced by frustration in quantum antiferromagnets

Abstract

We show strong numerical evidence in favor of an unexpected virtually gapless spectrum, with edge states localized at the boundaries, in frustrated spin-1/2 antiferromagnetic ladders with an odd number of legs. These features can be accurately reproduced by using a projected BCS wave function with a non-trivial pairing, that mixes even and odd reflection symmetries. This approach gives the correct classification of the excitations and provides a simple and very appealing picture of an unconventional spin-liquid phase stabilized by frustration.

4 pages and 4 figures

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Cited by in corpus (4)

• Spiral order by disorder and lattice nematic order in a frustrated Heisenberg antiferromagnet on the honeycomb lattice
• The spin-1/2 J1-J2 Heisenberg antiferromagnet on the square lattice: Exact diagonalization for N=40 spins
• Specific heat of underdoped cuprates: RVB versus Fermi arcs
• Improper s-wave symmetry for the electronic pairing in iron-based superconductors by first-principles calculation