Total reflection high-energy positron diffraction: An ideal diffraction technique for surface structure analysis

It is shown that the reflection high-energy positron diffraction (RHEPD) pattern from a Si(111)-(7 × 7) reconstructed surface for the total reflection condition, that is, the total reflection high-energy positron diffraction (TRHEPD) pattern, does not contain contributions from atoms in the bulk. Now, a method of observing the diffraction pattern formed only by the atoms on the topmost surface by a straightforward measurement of a bulk sample is available.