  We report low-frequency 1/f noise measurements of degenerately doped Si:P
\delta-layers at 4.2K. The noise was found to be over six orders of magnitude
lower than that of bulk Si:P systems in the metallic regime and is one of the
lowest values reported for doped semiconductors. The noise was found to be
nearly independent of magnetic field at low fields, indicating negligible
contribution from universal conductance fluctuations. Instead interaction of
electrons with very few active structural two-level systems may explain the
observed noise magnitude

Mesoscale and Nanoscale Physics