Bifurcation at the c=3/2 Takhtajan-Babujian point to the c=1 critical lines

TL;DR

This paper investigates the phase transitions in S=1 quantum spin chains near the Takhtajan-Babujian point, focusing on the crossover from a c=3/2 to a c=1 conformal field theory, using numerical methods to analyze critical behavior.

Contribution

It provides a detailed numerical analysis of the crossover from c=3/2 to c=1 conformal field theories in S=1 spin chains near the Takhtajan-Babujian point, identifying transition lines and critical properties.

Findings

Transition line between Haldane and dimer phases determined.

Conformal anomaly c and scaling dimensions calculated along the transition line.

Evidence of crossover from c=3/2 to c=1 conformal field theories.

Abstract

We study the S=1 quantum spin chains with bilinear, biquadratic, plus bond alternation in the vicinity of the S=1 Takhtajan-Babujian model. Transition line between the Haldane and the dimer phases are determined numerically. To see the crossover behavior from c=3/2 (k=2 SU(2) WZW model) at the Takhtajan-Babujian point to c=1 (k=1 SU(2) WZW model), we calculate the conformal anomaly c and scaling dimensions of the primary fields on the transition line.