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arXiv · 1408.2996

Optimal control of the signal to noise ratio per unit time for a spin 1/2 particle

M. Lapert·E. Assémat·S. J. Glaser·D. Sugny
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Abstract

We investigate the maximum signal to noise ratio per unit time that can be achieved for a spin 1/2 particle subjected to a periodic pulse sequence. Optimal control techniques are applied to design the control field and the position of the steady state, leading to the best signal to noise performance. A complete geometric description of the optimal control problem is given in the unbounded case. We show the optimality of the well-known Ernst angle solution, which is widely used in spectroscopic and medical imaging applications, over a large control space allowing use of shaped pulses.

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M. Lapert, E. Assémat, S. J. Glaser, D. Sugny. 2014-08-13. Optimal control of the signal to noise ratio per unit time for a spin 1/2 particle. https://doi.org/10.1103/physreva.90.023411

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