# Quantum Phase Transitions beyond the Landau&#x27;s Paradigm in Sp4 Spin System - Condensed Matter > Strongly Correlated Electrons

Abstract: We propose quantum phase transitions beyond the Landau-s paradigm of Sp4spin Heisenberg models on the triangular and square lattices, motivated by theexact Sp4$\simeq$ SO5 symmetry of spin-3-2 fermionic cold atomic systemwith only $s-$wave scattering. On the triangular lattice, we study a phasetransition between the $\sqrt{3}\times\sqrt{3}$ spin ordered phase and a $Z 2$spin liquid phase, this phase transition is described by an O8 sigma model interms of fractionalized spinon fields, with significant anomalous scalingdimensions of spin order parameters. On the square lattice, we propose adeconfined critical point between the Neel order and the VBS order, which isdescribed by the CP3 model, and the monopole effect of the compact U1 gaugefield is expected to be suppressed at the critical point.

Author: Yang Qi, Cenke Xu

Source: https://arxiv.org/