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arXiv:1804.00054 · Physical review. B./Physical review. B

Transition between algebraic and Z 2 quantum spin liquids at large N

Rufus Boyack, Chien-Hung Lin, Nikolai Zerf, Ahmed Rayyan, Joseph Maciejko

Published Jul 23, 2018• 23 citations
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Abstract

We present a field theory description of a quantum phase transition in two spatial dimensions between a $\text{U}(1)$ algebraic spin liquid with $N$ flavors of gapless two-component Dirac fermionic spinons and a gapped ${\mathbb{Z}}_{2}$ spin liquid. This transition is driven by spinon pairing and concomitant Higgsing of the emergent U(1) gauge field. For sufficiently large $N$, we find a quantum critical point with non-Gaussian exponents that is stable against instanton proliferation. We compute critical exponents using either $1/N$ or $\ensuremath{\epsilon}$ expansions, and give estimates of the critical value of $N$ below which the quantum critical point disappears.

DOI
10.1103/physrevb.98.035137

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