Ask any question about EPFL courses, lectures, exercises, research, news, etc. or try the example questions below.
DISCLAIMER: The Graph Chatbot is not programmed to provide explicit or categorical answers to your questions. Rather, it transforms your questions into API requests that are distributed across the various IT services officially administered by EPFL. Its purpose is solely to collect and recommend relevant references to content that you can explore to help you answer your questions.
It is shown by theory and expt. how coherent superpositions of quantum states in 3-level systems can be manipulated by irradiating 2 connected transitions with 2 resonant fields with suitably shaped time-dependent amplitudes and phases. Three variants are discussed; (i) adiabatic coherence transfer (ACT) between 2 transitions, which may be either allowed or forbidden; (ii) nonadiabatic transfer of coherence to a nonirradiated transition by controlled violation of adiabaticity (CVA); (iii) coherence transfer to a nonirradiated transition by antiparallel double resonant irradn. (APDRI). A geometrical representation of these expts. gives a clear phys. picture of the phenomena and provides a tool for the development of new methods. The principles are illustrated exptl. by applications to magnetic resonance of D (I = 1) in anisotropic phase at high magnetic field, but could also be applied to 3 level-systems in NQR, optics, and other areas of spectroscopy. [on SciFinder (R)]