Abstract

The recent identification of α-MnTe as a candidate altermagnet has attracted considerable interest, particularly for its potential application in magnetic random-access memory. However, the development of high-quality thin films — essential for practical implementation — has remained limited. Here, we report the epitaxial growth of centimeter-scale α-MnTe thin films on InP(111) substrates via molecular beam epitaxy (MBE). Through X-ray diffraction (XRD) analysis, we construct a MnTe phase diagram that provides clear guidance for stabilizing the pure α-MnTe phase, revealing that it is favored under high Te/Mn flux ratios and elevated growth temperatures. Cross-sectional electron microscopy confirms an atomically sharp film–substrate interface, consistent with a layer-by-layer epitaxial growth mode. Remarkably, these high-quality α-MnTe films exhibit a pronounced anomalous Hall effect (AHE) originating from Berry curvature, despite a net magnetic moment approaching zero — a signature of robust altermagnetic character. Our work establishes a viable route for synthesizing wafer-scale α-MnTe thin films and highlights their promise for altermagnet-based spintronics and magnetic sensing.

Abstract

The recent identification of α-MnTe as a candidate altermagnet has attracted considerable interest, particularly for its potential application in magnetic random-access memory. However, the development of high-quality thin films — essential for practical implementation — has remained limited. Here, we report the epitaxial growth of centimeter-scale α-MnTe thin films on InP(111) substrates via molecular beam epitaxy (MBE). Through X-ray diffraction (XRD) analysis, we construct a MnTe phase diagram that provides clear guidance for stabilizing the pure α-MnTe phase, revealing that it is favored under high Te/Mn flux ratios and elevated growth temperatures. Cross-sectional electron microscopy confirms an atomically sharp film–substrate interface, consistent with a layer-by-layer epitaxial growth mode. Remarkably, these high-quality α-MnTe films exhibit a pronounced anomalous Hall effect (AHE) originating from Berry curvature, despite a net magnetic moment approaching zero — a signature of robust altermagnetic character. Our work establishes a viable route for synthesizing wafer-scale α-MnTe thin films and highlights their promise for altermagnet-based spintronics and magnetic sensing.

Abstract

The recent identification of α-MnTe as a candidate altermagnet has attracted considerable interest, particularly for its potential application in magnetic random-access memory. However, the development of high-quality thin films — essential for practical implementation — has remained limited. Here, we report the epitaxial growth of centimeter-scale α-MnTe thin films on InP(111) substrates via molecular beam epitaxy (MBE). Through X-ray diffraction (XRD) analysis, we construct a MnTe phase diagram that provides clear guidance for stabilizing the pure α-MnTe phase, revealing that it is favored under high Te/Mn flux ratios and elevated growth temperatures. Cross-sectional electron microscopy confirms an atomically sharp film–substrate interface, consistent with a layer-by-layer epitaxial growth mode. Remarkably, these high-quality α-MnTe films exhibit a pronounced anomalous Hall effect (AHE) originating from Berry curvature, despite a net magnetic moment approaching zero — a signature of robust altermagnetic character. Our work establishes a viable route for synthesizing wafer-scale α-MnTe thin films and highlights their promise for altermagnet-based spintronics and magnetic sensing.

Abstract

The recent identification of α-MnTe as a candidate altermagnet has attracted considerable interest, particularly for its potential application in magnetic random-access memory. However, the development of high-quality thin films — essential for practical implementation — has remained limited. Here, we report the epitaxial growth of centimeter-scale α-MnTe thin films on InP(111) substrates via molecular beam epitaxy (MBE). Through X-ray diffraction (XRD) analysis, we construct a MnTe phase diagram that provides clear guidance for stabilizing the pure α-MnTe phase, revealing that it is favored under high Te/Mn flux ratios and elevated growth temperatures. Cross-sectional electron microscopy confirms an atomically sharp film–substrate interface, consistent with a layer-by-layer epitaxial growth mode. Remarkably, these high-quality α-MnTe films exhibit a pronounced anomalous Hall effect (AHE) originating from Berry curvature, despite a net magnetic moment approaching zero — a signature of robust altermagnetic character. Our work establishes a viable route for synthesizing wafer-scale α-MnTe thin films and highlights their promise for altermagnet-based spintronics and magnetic sensing.