Quantum criticality in the SO(5) bilinear-biquadratic Heisenberg chain
Quantum criticality in the SO(5) bilinear-biquadratic Heisenberg chain
The zero-temperature properties of the SO(5) bilinear-biquadratic Heisenberg chain are investigated by means of a low-energy approach and large-scale numerical calculations. In sharp contrast to the spin-1 SO(3) Heisenberg chain, we show that the SO(5) Heisenberg chain is dimerized with a twofold degenerate ground state. On top of this gapful …