1.引言作为热电致冷材料的化合物半导体Bi_2Te_3-Sb_2Te_3-Bi_2Se_3,迄今为止仍是室温条件下优值最高的材料。其优值所以超过3×10~(-3)/度。然而,当温度低于200k时,它们的优值将随温度的降低而迅速减小。从而限制了半导体致冷器致冷温度的进一步降低。不过,目前已经发现,若采用 Bi-Sb 固溶体合金,即使在很低的温度 1. Introduction Bi2Te3-Sb2Te3-Bi2Se3, a compound semiconductor that is a thermoelectric refrigerant, is by far the most merit material at room temperature. Therefore, the value exceeds 3 × 10 -3 / degree. However, their merit decreases rapidly with decreasing temperature when the temperature is below 200k. Thus limiting the further reduction of the refrigeration temperature of the semiconductor refrigerator. However, it has now been found that with Bi-Sb solid solution alloys, even at very low temperatures