What techniques are there for ensuring nonnegativity of various entries of matrix powers?

**Specific Question:** Consider a matrix $A\in SL_2(\mathbb R)$. Let $(A^n)_{i,j}$ denote the $(i,j)$ entry of the matrix power $A^n$. Under what conditions on $A$ does the following hold:
$$
\text{sgn}\ (A^n)_{i,j}=(-1)^{j+1}
$$