The tensor complementarity problem (\q, \mathcal{A}) is to
\mbox{ find } \x \in \mathbb{R}^n\mbox{ such that }\x \geq \0, \q +
\mathcal{A}\x^{m-1} \geq \0, \mbox{ and }\x^\top (\q + \mathcal{A}\x^{m-1}) =
0. We prove that a real tensor A is a (strictly) semi-positive
tensor if and only if the tensor complementarity problem (\q, \mathcal{A})
has a unique solution for \q>\0 (\q\geq\0), and a symmetric real tensor is
a (strictly) semi-positive tensor if and only if it is (strictly) copositive.
That is, for a strictly copositive symmetric tensor A, the tensor
complementarity problem (\q, \mathcal{A}) has a solution for all \q \in
\mathbb{R}^n
