Electrical properties of modulation-doped HgTe-CdTe superlattices

Growth of modulation‐doped HgTe‐CdTe superlattices (SLs) at very low temperatures (140 °C) by photoassisted molecular beam epitaxy is reported. SL layer thicknesses were intentionally chosen such that most of the SLs studied are inverted‐band semimetals or inverted‐band semiconductors. Both p‐ and n‐type samples were successsfully prepared and studied. The doped superlattices exhibit excellent electrical properties. Lack of carrier freeze‐out at low temperatures provides convincing evidence that modulation‐doping has been achieved.