کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1813207 | 1025632 | 2010 | 5 صفحه PDF | دانلود رایگان |

We report here electronic properties of a two-dimensional modulated superlattice nanostructure. Our sample, grown by MBE, had a period d=d1+d2 (90 layers) of d1=5.6 nm (HgTe)/d2=3 nm (CdTe). Calculations of the specters 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, 4.2 K,), shown that for each d1/d2, when d2 increase the gap Eg decrease to zero at the transition semiconductor to semimetal conductivity behavior and become negative accusing a semimetallic conduction. At 4.2 K, the sample exhibits p type conductivity with a Hall mobility of 8200 cm2/Vs. This allowed us to observe the Shubnikov-de Haas effect with p=1.80×1012 cm−2. Using the calculated effective mass (mHH*=0,297m0) of the degenerated heavy holes gas, the Fermi energy (2D) was EF=14 meV in agreement with 12 meV of thermoelectric power α. In intrinsic regime, α∼T−3/2 and RHT3/2 indicates a gap Eg=E1−HH1=190 meV in agreement with calculated Eg (Γ, 300 K)=178 meV. The formalism used here predicts that this sample is a narrow gap, two-dimensional modulated nanostructure and medium-infrared detector.
Journal: Physica B: Condensed Matter - Volume 405, Issue 3, 1 February 2010, Pages 936–940