  We present a physical scheme for implementing quantum phase estimation via
weakly coupled double quantum-dot molecules embedded in a microcavity. During
the same process of implementation, we can also realize the calibration of a
timepiece based on the estimated phase. We use the electron-hole pair states in
coupled double quantum-dot molecules to encode quantum information, where the
requirement that two quantum dots are exactly identical is not necessary. Our
idea can also be generalized to other systems, such as atomic, trapped ion and
linear optics system.
