Isotopes

It's one of the isotopes that can be found in the Earth's crust.

Isotopes are atoms that have the same number of protons, but different numbers of neutrons and thus different atomic weight values.

Scientists from the Lawrence Livermore National Laboratory report they were able to create a type of fusion reaction by bombarding a microscopic pellet of fuel with beams from 192 powerful lasers to compress its component parts — hydrogen isotopes known as deuterium and tritium — and fuse them together at the atomic level.