Controlled levitation of nanostructured thin films

They're using light to heat the bottom of a thin material. Bottom of material heats up, heats up the air underneath the material, hot air expands and makes it float. Controlling the strength of the light controls how much heat the disc generates and thus controls its height. Heating one side of the disc causes it to heat unevenly and move in the opposite direction.

Do I have that right? Hot air rises, so if you stick something light on the plume of hot air, it will also rise? I think birds discovered this millions of years ago.

A long string of the disks could lift larger payloads. I imagine a feather-like structure with strips of film stretched between inflated ribs.

> allowing payloads of up to 10 milligrams for sunlight-powered low-cost microflyers at altitudes of 50 to 100 km.

Interesting, but as-yet impractical.

This is cool

I wonder if it could be used as a sort of permanent radar chaff if coated with aluminium or something