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Chirp pulse sequences for broadband π rotation.

Sambeda Sarkar1, Rudra N Purusottam2, Ashutosh Kumar2

  • 1Department of Systems and Control Engineering, IIT Bombay, Powai-400076, India.

Journal of Magnetic Resonance (San Diego, Calif. : 1997)
|May 30, 2021
PubMed
Summary
This summary is machine-generated.

This study introduces novel chirp pulse sequences for broadband π rotations, crucial for spin echo sequences. These sequences utilize adiabatic passage for improved refocusing pulse performance in magnetic resonance imaging.

Keywords:
Adiabatic passageBroadbandChirp pulseRefocussingSpin echopi rotation

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Area of Science:

  • Magnetic Resonance Imaging
  • Quantum Control

Background:

  • Spin echo pulse sequences are fundamental in Magnetic Resonance Imaging (MRI).
  • Efficient refocusing pulses are critical for signal integrity and minimizing artifacts.
  • Broadband pulses are needed to excite or manipulate spins over a wide range of frequencies.

Purpose of the Study:

  • To develop and present novel chirp pulse sequences for broadband π rotations.
  • To evaluate these sequences as ideal refocusing pulse elements in spin echo sequences.
  • To explore various combinations of adiabatic passage elements for optimized performance.

Main Methods:

  • Design of composite chirp pulse sequences using three adiabatic passage elements.
  • Theoretical analysis of the broadband π rotation capabilities of these sequences.
  • Validation through numerical simulations and experimental verification.

Main Results:

  • Demonstration of broadband π rotation using the proposed chirp pulse sequences.
  • Identification of various effective sequence combinations.
  • Successful implementation of these sequences as refocusing elements.

Conclusions:

  • The presented chirp pulse sequences are effective for broadband π rotations.
  • These sequences offer a promising alternative for refocusing pulse elements in spin echo sequences.
  • The theoretical framework, simulations, and experiments confirm the utility of these composite sequences.