Objective: To introduce a simple quantitative model that highlights the essential parameters that determine electrical conduction: the density of states in the channel, D and the rates at which electrons hop in and out of the two contacts, labeled source and drain. This model is used to explain diverse phenomena such as (1) why a small conductor has a maximum conductance that it cannot exceed even with the best of contacts, (2) how this conductance quantum evolves into Ohm’s law for large conductors, (3) how even a hydrogen atom can exhibit thermoelectric effects, (4) how even symmetric devices can be rectifying due to asymmetric electrostatics, and (5) how the “voltage” varies spatially inside a nanoscale device.

This lecture is part 1 of 2.

NCN@Purdue Summer School 2008 National Science Fondation Intel Corporation

Researchers should cite this work as follows:

• Supriyo Datta (2008), "Lecture 1A: What and where is the resistance?," http://nanohub.org/resources/5211.

  BibTex | EndNote

1. course lecture
2. density of states
3. DOS
4. nanoelectronics
5. nanotransistors
6. quantum transport
7. transport/quantum