Take the 2-minute tour ×
Physics Stack Exchange is a question and answer site for active researchers, academics and students of physics. It's 100% free, no registration required.

What is $Z_2 $ topological index in spin liquid system? How to understand its physical picture in condensed matter?

share|improve this question
Are you taking about the orientation dependence of the ground state? –  Ryan Thorngren Sep 30 '12 at 21:55
As written in the answer below, there are no such index for spin liquids (as there is for time-reversal invariant topological insulators). Are you thinking about the so-called $\mathbb Z_2$ spin liquids? The $\mathbb Z_2$ does not refer to a topological index, but rather to the fact that the low-energy dynamics are described by a $\mathbb Z_2$ gauge theory. There are also so-called $SU(2)$ and $U(1)$ spin liquids. See arxiv.org/abs/cond-mat/0107071 for a partial classification. –  Heidar Oct 1 '12 at 13:53
Yes, I was thinking about the the $ Z_2 $ spin liquids. Thanks for your answer and reference. –  Jeremy Oct 3 '12 at 15:24
add comment

1 Answer 1

up vote 2 down vote accepted

Different spin liquids are extremely rich, and they cannot be described by $Z_2$ topological index. So there is no $Z_2$ topological index for generic spin liquids.

share|improve this answer
I don't understand why this answer is down-voted, since its 100 % correct. –  Heidar Oct 1 '12 at 13:54
add comment

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.