## Courses

## nanoHUB-U: Fundamentals of Nanoelectronics - Part A: Basic Concepts, 2nd Edition

Basic Concepts presents key concepts in nanoelectronics and mesoscopic physics and relates them to the traditional view of electron flow in solids.

First in a two part series, **Part A: Basic Concepts,** is designed to convey the key concepts developed in the last 20 years, which constitute the fundamentals of nanoelectronics and mesoscopic physics.

Second in the series, __Fundamentals of Nanoelectronics - Part B: Quantum Transport__, is now available as a free self-paced course on edX and nanoHUB-U.

## Short Description:

## Scientific Overview:

**Course Description: **

The modern smartphone is enabled by a billion-plus nanotransistors, each having an active region that is barely a few hundred atoms long. Interestingly the same amazing technology has also led to a deeper understanding of the nature of current flow on an atomic scale and my aim is to make these lessons from nanoelectronics accessible to anyone in any branch of science or engineering. I will assume very little background beyond linear algebra and differential equations, although we will be discussing advanced concepts in non-equilibrium statistical mechanics that should be of interest even to specialists.

In the first half of this course, we will introduce a new perspective connecting the quantized conductance of short ballistic conductors to the familiar Ohm's law of long diffusive conductors, along with a brief description of the modern nanotransistor. In the second half, we will address fundamental conceptual issues related to the meaning of resistance on an atomic scale, the interconversion of electricity and heat, the second law of thermodynamics and the fuel value of information.

Overall I hope to show that the lessons of nanoelectronics lead naturally to a new viewpoint, one that changes even some basic concepts we all learn in freshman physics. This unique viewpoint not only clarifies many old questions but also provides a powerful approach to new questions at the frontier of modern nanoelectronics, such as how devices can be built to control the spin of electrons.

This course was originally offered in 2012 on nanoHUB-U and the accompanying text was subsequently published by World Scientific. I have included the latest edition for those registered in this course.

## Prerequisites:

This course is intended to be broadly accessible to students in any branch of science or engineering. Students should have a basic familiarity with calculus and elementary differential equations. No prior acquaintance with quantum mechanics is assumed.

**Recommended Reading: **

*Lessons from Nanoelectronics: A New Perspective on Transport*, by Supriyo Datta, Purdue University

**Course Outline:**

### Unit 1: The New Perspective

L1.1: Introduction

L1.2: Two Key Concepts

L1.3: Why Electrons Flow

L1.4: Conductance Formula

L1.5: Ballistic (B) Conductance

L1.6: Diffusive (D) Conductance

L1.7: Connecting Ballistic (B) to Diffusive (D)

L1.8: Angular Averaging

L1.9: Drude Formula

L1.10: Summary

**Unit 2: Energy Band Model**

L2.1: Introduction

L2.2: E(p) or E(k) Relation

L2.3: Counting States

L2.4: Density of States

L2.5: Number of Modes

L2.6: Electron Density (n)

L2.7: Conductivity vs. Electron Density (n)

L2.8: Quantum Capacitance

L2.9: The Nanotransistor

L2.10: Summary

### Unit 3: What and Where is the Voltage

L3.1: Introduction

L3.2: A New Boundary Condition

L3.3: Quasi-Fermi Levels (QFL's)

L3.4: Current from QFL's

L3.5: Landauer Formulas

L3.6: What a Probe Measures

L3.7: Electrostatic Potential

L3.8: Boltzmann Equation

L3.9: Spin Voltages

L3.10: Summary

### Unit 4: Heat and Energy: Second Law & Information

L4.1: Introduction

L4.2: Seebeck Coefficient

L4.3: Heat Current

L4.4: One-level Device

L4.5: Second Law

L4.6: Entropy

L4.7: Law of Equilibrium

L4.8: Shannon Entropy

L4.9: Fuel Value of Information

L4.10: Summing up

**Course Reviews:**

- " I am a researcher in microelectronics fabrication with interests in molecular and organic electronics. This course is an excellent introduction to nanotransport. The strong points (a) Prof Datta is an excellent teacher and has put a lot of effort to cut down everything in small digestible pieces. (b) The formalism is simplified enough to transmit the message. It is advisable for someone following the course to compare always with standard texts of Solid State Theory, Semiconductors, Quantum and Statistical Mechanics. (c) I specially liked the clear presentation of the ballistic model, the relation to thermodynamics and the presentation of the MOS transistor. A couple of (not so) weak points. (a) the connection of ballistic to diffusive regime was clear but left something to be desired. I would like to si more elaboration specially regarding the time and the lambda parameter. (b) There are a few straight forward applications of the general current expression that could be discussed or worked out or at least referenced such the Richardson law, the Schottky diode, the Arrhenius dependence in hopping conductance or a couple of models in tunneling. Overall, excellent cource, I am looking forward for part 2!" ...posted anonymously on edX, Spring 2015
- "… the pedagogical imperative in research is very important to me, and so I really value a kindred spirit. Your (Datta's) online courses are just wonderful!"... Roald Hoffmann, http://en.wikipedia/wiki/Roald_Hoffmann, Cornell University
- "The course was just awesome .. Prof. Datta's style of delivering lecture is mind-blowing."...From anonymous student in previous offering.

## Course Resources

- A free nanoHUB.org account is required to access some course components.
- Online quizzes to quickly assess understanding of material after most video lectures.
- An online forum, hosted by nanoHUB. Students enrolled in the course will be able to interact with one another.

## Licensing

## Registration

This self-paced course is available at no cost.

**nanoHUB-U is powered by nanoHUB.org, the home for computational nanoscience and nanotechnology research, education, and collaboration.**