Studies of confined states and quantum size effects with scanning tunneling microscopy

Scanning tunneling microscopy (STM) provides new ways for studying electron confinement and quantum size effects and expands the range of materials and conditions under which such effects can be observed. Here we discuss three applications: (a) The confinement of electrons in metal surface states by surface steps or by corrals fabricated using single atoms, and the imaging of the probability amplitudes of the resulting confined states; (b) the detection of electron states involving confinement between the surface layer and sub-surface interfaces; (c) the observation of quantized conductance at room temperature using metal structures formed by the STM tip. © 1994.