SORDOR Pulses: Expansion of the Böhlen-Bodenhausen Scheme for Low-Power Broadband Magnetic Resonance

A novel type of efficient broadband pulses, called SORDOR (second order phase dispersion by optimized rotation pulses), has recently been introduced. In contrast to adiabatic excitation, SORDOR-90 pulses provide effective transverse 90° rotations throughout their bandwidth, with a quadratic offset dependence of the phase in the x,y-plane. Together with phase-matched SORDOR-180 pulses, this enables the Böhlen-Bodenhausen broadband spectroscopy approach for frequency-swept pulses to be extended to any type of 90°/180° pulse-delay sequence. Example pulse shapes are characterised in theory and experiment and an example broadband application is given with a 19F-PROJECT experiment for measuring T2-relaxation times without distortions due to J-coupling evolution.