Quadratic BSDEs with convex generators and unbounded terminal conditions

In Briand and Hu (Probab Theory Relat Fields 136(4):604-618, 2006), the authors proved an existence result for BSDEs with quadratic generators with respect to the variable z and with unbounded terminal conditions. However, no uniqueness result was stated in that work. The main goal of this paper is to fill this gap. In order to obtain a comparison theorem for this kind of BSDEs, we assume that the generator is convex with respect to the variable z. Under this assumption of convexity, we are also able to prove a stability result in the spirit of the a priori estimates stated in Karoui et al. (Math Finance 7(1):1-71, 1997). With these tools in hands, we can derive the nonlinear Feynman-Kac formula in this context.