A time crystal
Time crystals sound like talismans from a fantasy novel, but they're actually real quantum objects, generated for the first time in 2017. A time crystal is a unique state of matter, a group of ions lashed together with quantum links such that they shake, or oscillate, together at a repeating period. As long as the conditions they need to exist remain, time crystals become locked into a single moment in time; no matter how much energy gets pumped into them, they don't heat up or increase in entropy — effectively suspending the laws of thermodynamics as they're typically understood.