NMR-echo study of topological phase in two-level system

Two-quantum rotary echoes predicted by Bloch like equations for two-quantum transition have been observed in a multi-level NMR system of 27 Al nuclei in Al 2 O 3 . An rf field exactly at resonance to the two-quantum transition ( Δ m =2) was turned on at t =0 and its phase was shifted by 90° at t =τ. The echo at t =2τ was observed by using the technique of transfer of coherence reported previously. Characteristic dependence of the echo width upon inhomogeneity of rf field amplitude was confirmed experimentally.Two-quantum rotary echoes predicted by Bloch like equations for two-quantum transition have been observed in a multi-level NMR system of 27 Al nuclei in Al 2 O 3 . An rf field exactly at resonance to the two-quantum transition ( Δ m =2) was turned on at t =0 and its phase was shifted by 90° at t =τ. The echo at t =2τ was observed by using the technique of transfer of coherence reported previously. Characteristic dependence of the echo width upon inhomogeneity of rf field amplitude was confirmed experimentally.

Journal of the Physical Society of JapanJun 1, 197721 citations

Topological phases in two-dimensional systems

Emmanuel V. C. Lopes

Jul 18, 20250 citations

NMR Study in the Low-Dimensional Quantum Spin System

真治松本

Mar 25, 19980 citations

Phase-dependent decoherence of optical transitions in Pr3+:LaF3 in the presence of a driving field

Geoff J. Pryde, Matthew J. Sellars, N. B. Manson

The decoherence times of orthogonally phased components of the optical transition dipole moment in a two-level system have been observed to differ by an order of magnitude. This phase anisotropy is observed in coherent transient experiments where an optical driving field is present during extended periods of decoherence. The decoherence time of the component of the dipole moment in phase with the driving field is extended compared to ${T}_{2},$ obtained from two-pulse photon echoes, in analogy with the spin locking technique of NMR. This is the first phase-dependent investigation of optical decoherence in the presence of a driving field.The decoherence times of orthogonally phased components of the optical transition dipole moment in a two-level system have been observed to differ by an order of magnitude. This phase anisotropy is observed in coherent transient experiments where an optical driving field is present during extended periods of decoherence. The decoherence time of the component of the dipole moment in phase with the driving field is extended compared to ${T}_{2},$ obtained from two-pulse photon echoes, in analogy with the spin locking technique of NMR. This is the first phase-dependent investigation of optical decoherence in the presence of a driving field.

arXiv:quant-ph/0312070Physical Review BFeb 20, 20045 citations

{T}_{2},

obtained from two-pulse photon echoes, in analogy with the spin locking technique of NMR. This is the first phase-dependent investigation of optical decoherence in the presence of a driving field.