Supercharged Wireless Connections
What do the semiconductor physics group do?
Electricity seems very simple – you just flick a switch and there it is – but how often have you ever thought about what is happening to the electrons that make up that electricity? The electrons’’ behaviour can change depending on what material they are in. Materials can be divided into three categories according to their ability to conduct electrons: insulators, conductors and semi-conductors. In insulators, such as rubber and plastic charge does not flow at all. In conductors, such as metals, electric charge can flow easily. In semiconductors, such as doped silicon, the ability of the material to permit charge to flow can be controlled. Thus, semiconductors can range from insulating to conducting. This can be very useful; computer processors are based on the ability to switch currents on and off very quickly. Semiconductor transistors are well suited to this task, as they are able to go from conducting to insulating by simply applying a small voltage to a special terminal.
In the semiconductor physics group, we design, make and carry out experiments on new kinds of electrical devices to find out how electrons behave, and how we can control them. In the larger scope, beyond academic research, our work leads to faster, more energy efficient semiconductor devices and even brand new devices.
What will visitors see at your exhibit?
At this exhibit, you will see a wireless link being used to transmit music. Has your phone or laptop ever had problems buffering and being slow to download too many things? We are working on a new type of technology that could make this more than a 100 times faster. To do this we use higher frequency waves, terahertz waves. They allow a higher bandwidth but as you will see they have some drawbacks…they are absorbed by water.
What physics are used?
The physics that this exhibit uses focuses on the transmission of electromagnetic waves to transmit data wirelessly. To do this we use many different semiconductor components such as lasers, photodiodes, amplifiers and modulators. These are all items that are used in your home Wi-Fi.
Why is it useful?
Allows high-speed data rates at short distances, such as wireless monitors. It can also be used in space to allow satellites to communicate quickly – allowing faster internet speeds in remote areas.