Can we disappear like Harry Potter?

Well, no. Not now, maybe not ever. But we can do a lot of cool things that can, in particular circumstances, mimic true invisibility. As Alan Boyle explains, these include the use of "metamaterials" to make light flow around an object, active camouflage, when a surface equipped with light/color elements essentially recolors itself to look like the background behind it, to something really weird called "time lenses" which hide a moment of time rather than space: if I punch you and you don't see it because that moment of time was "hidden' by compressing and decompressing light, did I really punch you? Well, your face hurts, and something must have happened, but you would have no idea what. Sounds like a good idea for a comic superhero, but it's reportedly already been demonstrated (for 15 trillions of a second). Boyle provides links to articles on all these items, and others. Fascinating reading... if you can see it... :)