Chiral ordering in Heisenberg spin glasses in two and three dimensions

The nearest-neighbor Heisenberg spin glass in two and three dimensions is studied by means of a T=0 domain-wall renormalization-group method with a focus on the chiral ordering. In d=2 dimensions, both the spin and chiral components order at zero temperature with different correlation-length exponents, while d=3 appears to be just above the lower critical dimension of the chiral component ${\mathit{d}}_{\mathit{l}}^{\left(\mathit{c}\right)}$, though the possibility that ${\mathit{d}}_{\mathit{l}}^{\left(\mathit{c}\right)}$=3 cannot be ruled out. A chirality driven mechanism is proposed as a new possible mechanism of experimentally observed spin-glass transitions.