Qubit-qudit states with positive partial transpose
Qubit-qudit states with positive partial transpose
We show that the length of a qubit-qutrit separable state is equal to $\mathrm{max}(r,s)$, where $r$ is the rank of the state and $s$ the rank of its partial transpose. We refer to the ordered pair $(r,s)$ as the birank of this state. We also construct examples of qubit-qutrit separable …