Tamtam Proceedings - lamsin

0 0.05 0.1 0.15 0.2 0.25 0.3The two-band Schrödinger model 379120IpicT=300K10 −1100Current density (kA/cm 2 )80604020Ivalley0Log transmission coefficient10 010 −210 −310 −410 −510 −6TTcTv10 −70 0.5 1 1.5 2 2.5Energy (eV)Valence bandGap bandConduction bandVoltage (V)Figure 2. a)The current-voltage for an InAs/AlSb/GaSb/AlSb/InAs resonant interband tunneling with10Ang AlSb barriers and 30Ang GaSb well when P = 1.4 ∗ 1e + 6 eV.m. b) Calculated transmissioncoefficients of the interband resonant tunneling diode according to the two bands.To maximize the computing efficiency and to save the memory space, we have used aCholesky decomposition. We notice that this is not the unique method. Other methodshave been proposed such that in thesis of E. Polizzi (Ref. 4). He used an iterative methodwhich is a conjugate gradient with incomplete Cholesky preconditionor.4. Numerical resultsThe device simulated is a one dimensional RITD which consists of L b barrier widthand 1.97 eV height. The quantum well is of L w width. Then, the double barrier quantumwell region of the resonant interband consists of undoped GaSb well sandwiched betweenAlSb barriers. This region is separated from InAs electrode layers by 4.5 nm wide unintentionallydoped InAs space layers. Moreover, the conduction of InAs is chosen as theenergy reference (zero) point.The first important characteristic of this device is the simulation of the current voltagewhere the expression of the current is given byJ(x) = e(∫ +∞0g 0 (k) (Im(DΨ(x) • Ψ(x))) dk. (14)In figure 2-a), the device is run from 0 to 0.3 V olts in 0.01 increments. The peak currentI pic on the order of 110 kA/cm 2 is reached at a voltage 0.05 V olts. It correspondsto tunneling through the valence band. The peak-to-valley current (I pic /I valley ) ratio is8.3 at room temperature.In these heterostructure RITD, the device operation depends entirely on the unique fea-TAMTAM –Tunis– 2005