  Fundamental issues of 1/f noise in quantum nanoscience are reviewed starting
from basic statistical noise processes. Fundamental noise models based on
two-level systems (TLS) are described. We emphasize the importance of TLSs in
materials parameter fluctuations, such as dielectric constant. The present
understanding of 1/f noise in superconducting quantum interferometers and in
single electron devices is summarized. For coherent quantum nanoscience, we
introduce superconducting qubits and the relation between decoherence and 1/f
noise using the filter function formulation. We also clarify the qubit noise
spectroscopy and emphasize the importance of materials with reduced 1/f noise
for future quantum coherent nanodevices.
