Frequency Selective Control of an Ensemble Using RF Pulses Designed via the TOPS Algorithm in NMR Spectroscopy

• Published in: 2023 Ninth Indian Control Conference (ICC) pp. 85 - 89
• Main Authors: Jacob, Justin, Khaneja, Navin
• Format: Conference Proceeding
• Language: English
• Published: IEEE 18.12.2023
• Subjects: Bilinear control; Bloch equation; Broadband excitation; Broadband inversion; Chemical shift; Composite pulse; Magnetic resonance imaging; Nuclear magnetic resonance; Phase modulation; Proteins; Radio frequency; Resonant frequency; Scalar triple product; Similarity transformation; Spectroscopy; Water
• DOI: 10.1109/ICC61519.2023.10442936

NMR spectroscopy is all about manipulating the nuclear spin of an atom, and we use radio frequency (RF) pulses for this. This paper introduces the TOPS algorithm, which focuses on phase manipulation in RF pulse design. It addresses the requirement for selective excitation/inversion in MRI and protein resonance experiments and demonstrates the application of the TOPS-2 algorithm in designing phase-modulated frequency selective pulses. The paper presents the algorithm for designing pulses using the TOPS approach to achieve specific objectives such as selective inversion and excitation. Experimental validation of the selective pulse sequence is performed using a sample consisting of 0.5 % H 2 O in 99.5% D 2 O.