Disclosed is a memory device and method of operation thereof. The memory device may include a source region and a drain region of a first dopant type, the source and drain regions contain a first semiconductor material; a body region of a second dopant type, the body region being sandwiched between the source and drain regions, the body comprising a second semiconductor material; a gate dielectric layer over at least the body region; and a gate comprising a conductive material over the gate dielectric layer. Specifically, one of the first semiconductor material and the second semiconductor material is lattice matched with the other of the first semiconductor material and the second semiconductor material and has an energy gap smaller than the energy gap of the other of the first semiconductor material and the second semiconductor material.