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Consecutive circularly-polarized optical pulses generate and rotate electron spin polarization through optical orientation and the optical Stark effect. We perform time- and magnetic-field-dependent optical pump-probe measurements on gallium arsenide and observe a variable Overhauser field growth that depends on the external magnetic field and laser wavelength. We show that the time dependence of the nuclear spin polarization can be attributed to the time-averaged electron spin polarization produced along the external magnetic field direction.
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Dynamic Nuclear Polarization Enhanced Nuclear Spin Optical Rotation
Abstract Nuclear spin optical rotation (NSOR) has been investigated as a magneto‐optical effect, which holds the potential for applications, including hybrid optical‐nuclear magnetic resonance (NMR) spectroscopy and gradientless imaging. The intrinsic nature of NSOR renders its detection relatively insensitive, which has prevented it moving from a proof of concept to a method supporting chemical characterizations. In this work, the dissolution dynamic nuclear polarization technique is introduced to provide nuclear spin polarization, increasing the signal‐to‐noise ratio by several thousand times. NSOR signals of1H and19F nuclei are observed in a single scan for diluted compounds, which has made this effect suitable for the determination of electronic transitions from a specific nucleus in a large molecule.
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- Award ID(s):
- 1404548
- PAR ID:
- 10256769
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie International Edition
- Volume:
- 60
- Issue:
- 16
- ISSN:
- 1433-7851
- Page Range / eLocation ID:
- p. 8823-8826
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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