Multispin dynamics of the solid-state NMR free induction decay

作     者：H. Cho T. D. Ladd J. Baugh D. G. Cory C. Ramanathan 

作者机构：Department of Nuclear Science and Engineering Massachusetts Institute of Technology Cambridge Massachusetts 02139 USA Department of Applied Physics Stanford University Palo Alto California 94305 USA Institute for Quantum Computing University of Waterloo Waterloo Ontario Canada 

出 版 物：《Physical Review B》 (Phys. Rev. B Condens. Matter Mater. Phys.)

年 卷 期：2005年第72卷第5期

页      面：054427-054427页

核心收录：

学科分类：0808[工学-电气工程] 0809[工学-电子科学与技术（可授工学、理学学位）] 07[理学] 0805[工学-材料科学与工程（可授工学、理学学位）] 0702[理学-物理学] 

摘      要：We present a new experimental investigation of the NMR free induction decay (FID) in a lattice of spin-1∕2 nuclei in a strong Zeeman field. Following a π∕2 pulse, evolution under the secular dipolar Hamiltonian preserves the coherence number in the Zeeman eigenbasis, but changes the number of correlated spins in the state. The observed signal is seen to decay as single-spin, single-quantum coherences evolve into multiple-spin coherences under the action of the dipolar Hamiltonian. In order to probe the multiple-spin dynamics during the FID, we measured the growth of coherence orders in a basis other than the usual Zeeman eigenbasis. This measurement provides the first direct experimental observation of the growth of coherent multiple-spin correlations during the FID. Experiments were performed with a cubic lattice of spins (F19 in calcium fluoride) and a linear spin chain (F19 in fluorapatite). It is seen that the geometrical arrangement of the spins plays a significant role in the development of higher-order correlations. The results are discussed in light of existing theoretical models.