We propose a scheme to carry out quantum phase gate in one step by bichromatic radiation method with semiconductor quantum dots (QDs) embedded in a single mode microcavity. The spin degrees of freedom of the only excess conduction band electron are employed as qubits and excitonic states are used as auxiliary states. The nearest-neighbor coupling is not required because the cavity mode plays the role of data bus. We show how to perform quantum computing with properly tailored laser pulses and Pauli-blocking effect, without exciting the cavity mode.
AbstractLuminescent quantum dots (QDs) are emerging as a new class of biological labels with unique properties and applications that are not available from traditional organic dyes and fluorescent proteins. Here we report new developments in using semiconductor quantum dots for quantitative imaging and spectroscopy of single cancer cells. We show that both live and fixed cells can be labeled with multicolor QDs, and that single cells can be analyzed by fluorescence imaging and wavelength-resolved spectroscopy. These results raise new possibilities in cancer imaging, molecular profiling, and disease staging.
Magneto-optics of layers of semiconductor quantum dots and nano-rings