Characterizations of Square Roots of Unitary Weighted Composition Operators on H2

Abstract

In this paper we study the square roots of unitary weighted composition operators on the Hardy space H2, i.e., Wf,φ when Wg,ψ=Wf,φ2 is unitary. In particular, we provide the explicit forms of the symbol functions φ and f of such Wf,φ. Moreover, we show that the square roots Wf,φ of a unitary weighted composition operator are normal. Finally, we investigate several properties of such Wf,φ. © 2021, The Author(s), under exclusive licence to Springer Nature Switzerland AG.