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arXiv · 1608.03068

Creating arbitrary quantum vibrational states in a carbon nanotube

Heng Wang·Guido Burkard
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Abstract

We theoretically study the creation of single- and multi-phonon Fock states and arbitrary superpositions of quantum phonon states in a nanomechanical carbon nanotube (CNT) resonator. In our model, a doubly clamped CNT resonator is initialized in the ground state and a single electron is trapped in a quantum dot which is formed by a electric gate potential and brought into the magnetic field of a micro-magnet. The preparation of arbitrary quantum phonon states is based on the coupling between the mechanical motion of the CNT and the electron spin which acts as a non-linearity. We assume that electrical driving pulses with different frequencies are applied on the system. The quantum information is transferred from the spin qubit to the mechanical motion by the spin-phonon coupling and the electron spin qubit can be reset by the single-electron spin resonance. We describe Wigner tomography which can be applied at the end to obtain the phase information of the prepared phonon states.

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Heng Wang, Guido Burkard. 2016-08-10. Creating arbitrary quantum vibrational states in a carbon nanotube. https://doi.org/10.1103/physrevb.94.205413

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