Structural and magnetic effects on thermal emittance of La 1−x Sr x MnO 3 from the first principles calculation

Generalized gradient approximation (GGA) exchange-correlation functional was used in the first-principles method to calculate thermal emittance of La1−xSrxMnO3 (LSMO). The effects of structure and magnetism on thermal emittance of LSMO were systematically investigated by the complex dielectric function. It is found that the LSMO with orthorhombic structure has a higher thermal emittance than that with rhombohedral structure at the same temperature. When the magnetism varying with temperature of LSMO is put into consideration, the magnetic different make a significant change on thermal emittance and the variation of thermal emittance of La0.75Sr0.25MnO3 is the biggest among x=0, 0.2, 0.25, 0.5. It is found that thermal emittance have a low value at the low temperature and have a high value at the high temperature, due to the unique feature of variable thermal emittance based on metal-insulator transition, which makes LSMO attractive as potential thermal control materials.