- #1
McKendrigo
- 26
- 0
Hi there, I'm a bit confused as to the meaning of the following figure, for the quantum well case:
I understand that with the quantum dot, since the states are completely quantised you get the delta functions - states only exist at certain energies so the DOS at these energies is non zero (and zero at all other energies).
The quantum well case confuses me though. I understand that the energy levels within a quantum well to be quantised in one dimension. However, if the energy levels are quantised, why is the DOS not zero between these energy levels? In other words, why are there flat 'steps' rather than a delta function?
I can follow the maths behind the derivation of the DOS for a quantum well or dot, but without really grasping the physical meaning of what it tells us for the QW. Any help would be appreciated!
I understand that with the quantum dot, since the states are completely quantised you get the delta functions - states only exist at certain energies so the DOS at these energies is non zero (and zero at all other energies).
The quantum well case confuses me though. I understand that the energy levels within a quantum well to be quantised in one dimension. However, if the energy levels are quantised, why is the DOS not zero between these energy levels? In other words, why are there flat 'steps' rather than a delta function?
I can follow the maths behind the derivation of the DOS for a quantum well or dot, but without really grasping the physical meaning of what it tells us for the QW. Any help would be appreciated!