Nanowire
Transverse quantization, ballistic transport and conductance quantization in nanowires
Parameters
Subband Dispersion E(k)
Transverse Energy Levels
Nanowire — Quiz
Q1. The conductance quantum G₀ = 2e²/h ≈ 77.48 μS. The factor 2 means:
A
Two conducting electrodes
B
Two transverse directions
C
Spin degeneracy (↑ and ↓)
D
Two subbands
Q2. The condition for ballistic transport is:
A
L ≫ l_mfp
B
L ≪ l_mfp
C
L = l_mfp
D
T = 0 K
Q3. When nanowire width W is doubled (W → 2W), the first subband threshold E₁₁:
A
Doubles
B
Quadruples
C
Decreases 4 times
D
Decreases 2 times
Q4. In diffusive regime, nanowire resistance R vs length L:
A
R ∝ L (Ohm's law)
B
R = const (L-independent)
C
R ∝ L²
D
R ∝ 1/L