Fundamentals of Current Flow

Very different from what is taught in standard courses, "Fundamentals of Current Flow" provides a unified conceptual framework for ballistic and diffusive transport of both electrons and phonons - essential information for understanding nanoelectronic devices.

The traditional description of electronic motion through a solid is based on diffusive transport, which means that the electron takes a random walk from the source to the drain of a transistor, for example. However, modern nanoelectronic devices often have channel lengths comparable to a mean free path so that electrons travel ballistically, or "like a bullet."

Verified students taking this course will be required to complete three (3) proctored exams using the edX online Proctortrack software. To be sure your computer is compatible, see Proctortrack Technical Requirements.

Nanoscience and Technology MicroMasters ®

Fundamentals of Current Flow is one course in a growing suite of unique, 1-credit-hour short courses developed in an edX/Purdue University collaboration. Students may elect to pursue a verified certificate for this specific course alone or as one of the six courses needed for the edX/Purdue MicroMasters® program in Nanoscience and Technology.

For further information and other courses offered, see the Nanoscience and Technology MicroMasters® page. Courses like this can also apply toward a Purdue University MSECE degree for students accepted into the full master’s program.

Week 1: The New Perspective

1.1 Introduction
1.2 Two Key Concepts
1.3 Why Electrons Flow
1.4 Conductance Formula
1.5 Ballistic (B) Conductance

Week 2: The New Perspective (Continued)

1.6 Diffusive (D) Conductance
1.7 Connecting B to D
1.8 Angular Averaging
1.9 Drude Formula
1.10 Summing Up

Week 3: Energy Band Model

2.1. Introduction
2.2. E(p) or E(k) Relation
2.3. Counting States
2.4. Density of States
2.5. Number of Modes

Week 4: Energy Band Model (Continued)

2.6. Electron Density (n)
2.7. Conductivity vs. n
2.8 - 2.9 Bonus Lectures; NOT covered on exams
2.10 Summing Up

Week 5: What and Where is the Voltage

3.1 Introduction
3.2 A New Boundary Condition
3.3 Quasi-Fermi Levels (QFL's)
3.4 Current from QFL's
3.5 Landauer Formulas
3.6 - 3.10 Bonus Lectures; NOT covered on exams

Epilog: Looking Forward-From Semiclassical to Quantum; Bonus Lectures; NOT covered on exams

Text: S. Datta, "Lessons from Nanoelectronics", Part A: Basic Concepts,
World Scientific, Second Edition 2017

The manuscript will be available for download on the course's website.