A pet-friendly ball that follows you around the house and self-inventorying fridges are just some of the gadgets on show at ...

This cube of germanium on a silicon nitrate membrane can be cooled to about 200mK by four chip-scale refrigerators (the four small light blue rectangles at the midpoints of the membrane perimeter).

Researchers have combined two tiny but powerful inventions on a single microchip, a cryogenic sensor and a micro-refrigerator. The combination offers the possibility of cheaper, simpler and faster ...