Formation of device-oriented InGaAs coupled quantum structures by selective MBE growth on patterned InP substrates

Attempts were made to realize device-oriented InGaAs coupled quantum structures by selective molecular beam epitaxy (MBE) on specially designed patterned InP substrates. At first, selective MBE growth of individual quantum wires (QWRs) and quantum dots (QDs) were established. By combining these growths, InGaAs/InAlAs QWR–QD–QWR coupled structures and QWR Y-branch couplers were successfully formed. The QWR–QD–QWR coupled structure realized a double-barrier potential profile needed for a single-electron transistor. A QWR honeycomb network consisting of the QWR Y-branch couplers seems promising for constructing quantum device networks and quantum/classical interconnections.