[gji]

Andrea Morello's devices are essentially quantum dots - isolated electrons that behave like they are bound to a single atom. Unfortunately, almost all quantum dots require dilution refrigerators. These things are past liquid nitrogen and even liquid helium - they use interesting phase change properties of a mix of helium-3 and helium-4 to lower the temperature to hundreds of millikelvin.

Really the only game in town currently for room-temperature quantum computing are impurity centers in diamond (most commonly nitrogen-vacancy centers). Unfortunately, there are still many difficulties there, especially since nanofabrication of diamond and precise implantation of the impurities is still a new field.