Everyday atoms: a night of the science of our day to day

From tracking the movement of the stars to modern atomic clocks; I will talk about the history of timekeeping and why better clocks are becoming more and more important. The best clocks today rely on atoms cooled to temperatures around one million times lower than outer space. We will cover how this is done and why you should care.

Quantum sensing probably evokes images of complex equipment, filling darkened laboratories with heavy steel chambers and powerful lasers. However, for magnetic measurements this is not the case. With our pocket-sized quantum magnetic sensor we measure magnetic fields from the Earth, our atmosphere and our own bodies, using ground-breaking sensitivity to uncover hidden signals. I will show how this sensor uses the quantum states of caesium atoms to powerfully amplify magnetic signals. I will also discuss a range of real-world applications, ranging from navigating without a GPS signal to real-time measurements of the human brain thinking.

The LED light bulb, that you now buy in the supermarket, won its inventors the Nobel prize in 2014 "for the invention of efficient blue light-emitting diodes which has enabled bright and energy-saving white light sources". The key material used to manufacture blue LEDs is the semiconductor gallium nitride (GaN). GaN does not exist in nature - the temperatures and pressures required to produce it are too high. We use special techniques to "grow" this material. We will discuss how blue LEDs are made, and how the region of the LED which emits the light comprises a layer around 10 atoms thick.