| 摘要 |
PURPOSE:To obtain the title interference element having a nearly theoretical value of conductance by a method wherein the first branch point is quantum point contact structured, while the length between the second branch point and a drain electrode is specified to exceed the Fermi wavelength. CONSTITUTION:The title phase interference element is provided with a source electrode 11 and a drain electrode 12, gate electrodes 17, 18. Besides, no impurity added GaAs, no impurity added GaAs/Alx Ga1-xAs as well as GaAs/AlxGa1-xAs whereto Si in specific concentration is added are formed while quadratic electron gas is fed to the interface between said elements. At this time, the electronic gas is depleted along the electrode shape by the metallic gate electrodes 17, 18 so that a quantum point contact 15, paths 13, 14 branched in ring shape and an interference promoting path 19 may be formed. Finally, respective metallic gate electrodes are formed meeting the requirements for the gap W' of 0.2mum of respective electrodes and the interference promoting channel length Le exceeding the Fermi wavelength of 0.2mum. |
