English

Encoding multiple quantum coherences in non-commuting bases

Quantum Physics 2007-05-23 v1

Abstract

Multiple quantum coherences are typically characterised by their coherence number and the number of spins that make up the state, though only the coherence number is normally measured. We present a simple set of measurements that extend our knowledge of the multiple quantum state by recording the coherences in both the xx basis and the usual zz basis. The coherences in the two bases are related by a similarity transformation. We characterize the growth of the multiple quantum coherences via measurements in the two bases, and show that the rate varies with the coefficient of the driving term in the Hamiltonian. Such measurements in non-commuting bases provides additional information over the 1D method about the state of the spin system. In particular the measurement of coherences in a basis other than the usual zz basis allows us to study the dynamics of the spin system under Hamiltonians, such as the secular dipolar Hamiltonian, that conserve zz basis coherence number.

Keywords

Cite

@article{arxiv.quant-ph/0408167,
  title  = {Encoding multiple quantum coherences in non-commuting bases},
  author = {Chandrasekhar Ramanathan and Hyungjoon Cho and Paola Cappellaro and Gregory S. Boutis and David G. Cory},
  journal= {arXiv preprint arXiv:quant-ph/0408167},
  year   = {2007}
}