We report here manifestation of resonant state and transition semiconductor-semimetal inducted by temperature in magneto-transport properties and bands structure in HgTe (d1=40 nm)/CdTe(d2=15 nm) superlattice (SL) grown by MBE. Calculations of the spectres of energy E(d2), E(kz) and E(kp), respectively, in the direction of growth and in plane of the superlattice; were performed in the envelope function formalism. The energy E(d2, Γ, 77 K), shown that when d2 increase the gap Eg decrease to zero at the transition semiconductor to semimetal conductivity behaviour (at d2=11,5 nm) and become negative accusing a semimetallic conduction. At 4.2 K, the sample exhibits n type conductivity with a Hall mobility of 1500 cm2/Vs. The weak-field Hall coefficient present a small maximum at about 30 K attributed to the presence of an acceptor resonant state. In intrinsic regime, RH T3/2 indicates a gap Eg = 5,3 meV in agreement with calculated Eg(Γ, 300 K)= E1-HH1 =6 meV. The later gap Eg(T) goes to zero at T=148 K with a transition semimetal to semiconductor conductivity. The formalism used here predicts that this sample is a narrow gap semimetallic, two-dimensional and far-infrared detector.
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