Department of Physics
Condensed Matter Seminar

Harnessing quantum coherence of electron and/or nuclear spins for new applications is an interesting research endeavor, holding much promise for high-precision metrology, coherent spintronics, and quantum information processing. However, progress in these areas is limited, because quantum coherence is easily destroyed by interaction with environment. This decoherence phenomenon, being of fundamental importance, is currently under active investigation. I will discuss numerical approaches to modeling of decoherence, and show how these simulations help to understand non-trivial decoherence regimes in quantum dots and in NMR experiments, where spins exhibit interesting long-time quantum dynamics. Moreover, the numerical simulations play an important role in analyzing various quantum control protocols designed for suppressing decoherence in spin systems. Our numerical results show that specially designed protocols can increase the coherence time by orders of magnitude, and in some cases, even completely "freeze" decoherence.