Control of ferromagnetic Curie temperature and topological Hall effect in chromium telluride thin films

Chromium telluride (Cr_1-δTe) has been known as a p-type ferromagnetic metal with varied Curie temperatures (T_c = 170 K – 340 K). Recently report of topological Hall effect (THE) suggested the skyrmion phase formation (Nano Research, 11, 3116 (2017)). However, the origin of THE as well as the various T_c among the Cr_1-δTe phases was not clearly understood yet. Here, we investigate two different types of Cr_1-δTe thin films with different T_c via different growth conditions to understand the origin of the various T_c. We also discuss the THE-like signal in our Hall measurements, with complementary microscopic and spectroscopic evidences, to address the origin of observed THE-like signal in this peculiar magnetic thin film system.