3. The Colour of Electron-Hole Magic

About this Lecture

Lecture

In this mini-lecture, we discuss how semiconductors can be used to create light of various colours and transform light into electrical energy. As we move through this mini-lecture, we consider: (i) applying an electric field to a semiconductor, which causes the electrons to flow in one direction and the holes to flow in the opposite direction; (ii) how connecting n-type and p-type semiconductors creates a PN-junction that turns electric energy into light and is how LEDs are made; (iii) how we can shine light on another type of PN-junction to get electrical energy, which is how solar cells are made; (iv) the different types of semiconductor materials used to create different coloured LEDs and lasers; and (v) silicon as a great material for solar cells.

Course

In this course Professor Oleg Makarovskiy (University of Nottingham) explores semiconductors and their relevance in the current Information Age. In the first mini-lecture, we introduce the ages of human advancement, from the Stone Age up until the current Information Age, and consider the advancements in computers and information made in the 20th century. In the second mini-lecture, we discuss what a semiconductor is and how you can make one using electrons and ‘holes.’ In the third mini-lecture, we consider how semiconductors can be used to create light of various colours (LEDs) and transform light into electrical energy (solar cells). In the fourth mini-lecture, we explore how we can control semiconductor colour and how we can make low-dimensional semiconductors, such as quantum dots. In the fifth mini-lecture, we focus on understanding diodes and transistors and how these can be used to create microchips used in computers. Finally, in the sixth mini-lecture, we consider the next advancement in our Information Age, quantum information technology, and the role semiconductors play in this new Quantum Information Age.

Lecturer

Oleg Makarovskiy is an Associate Professor in the School of Physics & Astronomy at the University of Nottingham. His research focuses on experimental semiconductor physics, quantum phenomena in semiconductor nanostructures, and their applications in functional electronic and optoelectronic devices.