Time symmetry: an application to shaped pulse excitation of spin-1 systems.
The role of time symmetry in the design of amplitude-modulated (shaped) pulses for spin-1 excitation is examined. The quaternion calculus is used to calculate the quaternion elements (Euler-Rodrigues parameters) of each shaped pulse. In this manner, it is shown how the simplicity and compactness of the Euler-Rodrigues parametrization can be used to significantly expedite a computer search for optimal time-symmetric shaped pulses. Theoretical and experimental tests of a new class of symmetric quadrupole-shaped (SQUASH) pulses identified by this procedure show a significant improvement in both excitation bandwidth and efficiency in comparison to the time-asymmetric QUASH shaped pulse previously identified.
Habot
S
S
Department of Physics, The University of Lethbridge, AB, Canada.
Lu
D
D
Tagg
N J
NJ
Gall
G R
GR
Siminovitch
D J
DJ
D009682:Magnetic Resonance Spectroscopy / Q000295:instrumentation / Q000379:methods*; D008432:Mathematical Computing