Field effect transistors (FET) including quantum layers. A FET may include a substrate, and an oxide layer disposed over the substrate. The oxide layer may include a first section and a second section positioned adjacent the first section. The FET may also include a first quantum layer disposed over the first section of the oxide layer, and a second quantum layer disposed over the second section of the oxide layer, and a first segment of the first quantum layer. Additionally, the FET may include a drain region disposed directly over a second segment the first quantum layer. The second segment of the first quantum layer may be positioned adjacent the first segment of the first quantum layer. The FET may further include a source region disposed over the second quantum layer, and a channel region formed over the second quantum layer, between the drain region and the source region.