Quantum of Conductance

Question 1

Give the equation for the current of a specific mode.

Answer 1

I = e v_g g(E_f) e V

Question 2

Give the Landauer resistance.

Answer 2

R_L = 1/G_o = h/2e^2 ~ 12.9 k-Ohms

Question 3

Describe the Coulomb Blockade.

Answer 3

energy to charge on electrode of a capacitor must be much larger than kT to avoid +/- e- thermally.

Question 4

Describe the uncertainty principle in regards to a quantum dot.

Answer 4

Δt = R_t C_dot - time to charge
ΔtΔE_c ~ h
This give a limit on the Resistance so e- can’t tunnel.

Question 5

How must the gate-source voltage vary to add a new electron to the QD?

Answer 5

It must increase in increments of e/C_g.
Starting from min. gate voltage e/2C_g.