  We propose a string theory construction which allows us to study properties
of the potential of two heavy quarks coupled to a light quark. In such a case,
the potential is a function of separation between the heavy quarks. The results
show the universality of the string tension and factorization at small
separations expected from heavy quark-diquark symmetry. In addition, we make an
estimate of the string breaking distance. With the parameter values we use,
this distance is found to be almost the same as that for the heavy
quark-antiquark potential. We also discuss the heavy quark-quark potential and
its relation to Lipkin rule.
