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R. G. Herb Condensed Matter Seminar
Resonant Passage of Spin States in a Triple Quantum Dot
Date: Thursday, November 17th
Time: 10:00 am
Place: 5310 Chamberlin
Speaker: Xuedong Hu, University of Buffalo
Abstract: Experimental and theoretical research on spin qubits in quantum dots are progressing toward systems with multiple spins in multiple dots. Among the many quantum information processing tasks that can be accomplished by such a multi-qubit system is the coherent transfer of quantum states on chip, which is an essential capability of a practical quantum computer. In this talk I will discuss our recent work on the physics of adiabatic quantum teleportation in a triple dot system. In particular, we show that a teleportation process over a three-spin chain can be mapped exactly onto two parallel and coherent adiabatic passages, one for each spin orientation. When the time evolution is not adiabatic, we find that the fidelity of information transfer displays a strong oscillatory behavior, and it is possible to have high fidelity when the switching frequency of the qubit interactions is a subharmonic of the characteristic energy splitting of the three-spin system. This resonant operation of an adiabatic passage protocol of spin states is both fast and robust, and points to a new way to perform other quantum gates.
Host: Coppersmith
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