Critical behavior of a novel layered ferromagnetic semiconductor Cr1.17Ga1.47Se4

Abstract

Layered magnetic semiconductors have attracted considerable interest due to their rich magnetic properties and potential applications in low-dimensional spintronics. Here, we report a novel layered magnetic semiconductor, Cr1.17Ga1.47Se4, featuring CrGa2Se4 slabs interleaved with a partially occupied Cr layer. Transmission spectrum, electrical transport, and magnetization measurements reveal that Cr1.17Ga1.47Se4 is a ferromagnetic semiconductor with an optical bandgap of 1.12 eV and a Curie temperature of 34 K. A comprehensive analysis based on modified Arrott plots, the Kouvel–Fisher method, and scaling relations yields a self-consistent set of critical exponents, β  = 0.362, γ  = 1.381, and δ  = 4.81. These exponents are close to those obtained from renormalization group analysis, indicating that Cr1.17Ga1.47Se4 belongs to the three-dimensional Heisenberg system with long-range magnetic interactions. Our results provide a platform for exploring two-dimensional magnetic semiconductors and provide insights into the nature of magnetism of layered magnetic semiconductors.