US Patent 7880162 Quantum device, control method thereof and manufacturing method thereof

A quantum dot (22) is formed on a GaAs substrate (20). In the quantum dot (22), a single electron exists. A cap layer (26) is formed on a surrounding area of the quantum dot (22), and a barrier layer (28) is formed thereon. A quantum dot (30) for detection is formed on the barrier layer (28). Then, a cap layer (34) covering the quantum dot (30) and the like is formed.