Antimatter may be very useful in the future, for fueling spaceships and curing cancer, but it can be used as a destructive weapon like making bombs with antimatter-matter reaction. When antimatter is created, it will annihilate in a fraction of seconds leaving energy and a burst of light, since the whole universe we live in is made of matter, and when matter and antimatter meet they will disappear because they have an opposite charge.
Artist’s impression of a cloud of trapped antihydrogen atoms. Image credit: Chukman So.
So why would we spend 62.5 trillion $ on 1 gram of a material that will disappear the moment it is created? In fact, we can trap antimatter and conserve it for a couple of seconds before it annihilates with ordinary matter, but this is done in large laboratories like CERN. It is hard to keep something away from matter when everything is made of matter, thus you cannot trap the antimatter particle in a fancy container, you can't let the antimatter particle touch the air, because air is made of matter.
So how to keep that antimatter particle away from matter? Scientists used a magnetic field to hold the antimatter particle and trap it, what's happening here is that energy traps the antimatter that we then conserve in a magnetic bottle that is shaped like a bathtub.
An artist’s impression of an antihydrogen atom – a negatively charged antiproton orbited by a positively charge anti-electron, or positron – trapped by magnetic fields. (Image by Katie Bertsche)
On 26 April 2011 ALPHA trapped 309 anti-hydrogen atoms for a period of 17 minutes. The ability to store antimatter is getting better with technological development and new techniques implemented by scientists and engineers.
Artistic representation of ALPHA magnetic trap (image source: Chukman So, copyright © 2011 Wurtele Research Group.)