Eigenvalues of non self-adjoint Toeplitz operators near an elliptic critical value with analytic regularity

TL;DR

This paper analyzes the eigenvalues of non self-adjoint Toeplitz operators near elliptic critical values, providing asymptotic expansions and resolvent estimates using advanced semiclassical and symbolic calculus techniques.

Contribution

It develops new semiclassical tools and normal form reductions to determine eigenvalue asymptotics for non self-adjoint Toeplitz operators near elliptic critical points.

Findings

Eigenvalues have asymptotic expansions near critical values.

Resolvent estimates are established for weighted norms.

Normal form reduction simplifies the analysis of general symbols.

Abstract

In this article, we determine the spectrum of real-analytic, non self-adjoint Toeplitz operators on compact K{\"a}hler manifolds and on the complex plane, on neighbourhoods of critical values of the symbol. We consider specifically critical values of the symbol on which its Hessian is elliptic and we get asymptotic expansion on eigenvalues in a neighbourhood with quantisation conditions similar to Bohr-Sommerfeld. To do so, we recall and further develop analytic semiclassical tools, in particular the symbolic calculus of complex Fourier integral operators using contour deformation. We detail the well known case of operators with quadratic symbols, and we treat a general case through normal form reduction. Finally, we prove resolvent estimates on norms with weights that come from the non-real part of the symbol.