Hybridizing anomalous Nernst effect in artificially tilted multilayer based on magnetic topological material

Abstract: Transverse thermoelectric conversion holds significant potential in addressing complex challenges faced by classical Seebeck/Peltier modules. A promising transverse thermoelectric phenomenon is the anomalous Nernst effect (ANE) originating from nontrivial band structures in magnetic topological materials. However, the currently reported performance for ANE in topological materials, e.g., Co$_2$MnGa, remains insufficient for practical thermoelectric applications. Here, we unveil a new availability for ANE by integrating magnetic topological materials into artificially tilted multilayers (ATMLs), known to exhibit the structure-induced transverse thermoelectric conversion due to the off-diagonal Seebeck effect. Our experiments reveal that the transverse thermoelectric performance in Co$_2$MnGa-based ATMLs is improved through the hybrid action of ANE and the off-diagonal Seebeck effect, with the modulation of performance dependent on magnetization being significantly greater than the performance achievable with ANE alone. This unconventional synergy underscores the importance of hybrid transverse thermoelectric conversion and paves a way for advancing thermoelectric applications using magnetic materials.