  This paper considers the problem of robust stability for a class of uncertain
nonlinear quantum systems subject to unknown perturbations in the system
Hamiltonian. The nominal system is a linear quantum system defined by a linear
vector of coupling operators and a quadratic Hamiltonian. This paper extends
previous results on the robust stability of nonlinear quantum systems to allow
for quantum systems with dynamic uncertainties. These dynamic uncertainties are
required to satisfy a certain quantum stochastic integral quadratic constraint.
The robust stability condition is given in terms of a strict bounded real
condition. This result is applied to the robust stability analysis of an
optical parametric amplifier.
