Generalized Airy operators

Abstract We study the behaviour of the norm of the resolvent for non-self-adjoint operators of the form $A := -\partial_x + W(x)$ , with $W(x) \ge 0$ , defined in ${L^2}({\mathbb{R}})$ . We provide a sharp estimate for the norm of its resolvent operator, $\| (A - \lambda)^{-1} \|$ , as the spectral parameter diverges $(\lambda \to +\infty)$ . Furthermore, we describe the C0-semigroup generated by −A and determine its norm. Finally, we discuss the applications of the results to the asymptotic description of pseudospectra of Schrödinger and damped wave operators, and also the optimality of abstract resolvent bounds based on Carleman-type estimates.