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Auger electron spectroscopy (AES) as a method to characterize the ferroelectric polarization domains in magnesium-doped lithium niobate crystals is demonstrated. Preliminary measurements on a test sample show a clearly identifiable relative shift in the energy of the Auger oxygen KLL transition peak between poled (inverted) and un-poled domains. Auger electrons detected from the negative polarization domains (-Z) have a higher energy than those from the positive domains indicating a lower ionization energy at the -Z domain surface. The degree of electron energy separation between the −Z and +Z domains was found to be dependent on proximity to the domain boundary and was potentially diminished by the accumulated charge under the incident primary beam. Polarization domain resolution is demonstrated on both the micron and millimeter scale, suggesting potential applicability of this technique to surface investigation and domain structure characterization of nonlinear optical devices such as periodically poled lithium niobate.
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Auger electron spectroscopy mapping of lithium niobate ferroelectric domains with nano-scale resolution
The +/−Z ferroelectric domains in periodically poled lithium niobate are characterized with Auger electron spectroscopy. The -Z domains have a higher Auger O-KLL transition amplitude than the +Z domains. Based on this, Auger electron spectroscopy mapping can be used on the O-KLL peak to image the +/-Z domain structure. This new characterization technique is confirmed with HF etching, and compared to SEM imaging. Spatial resolution down to 68 nm is demonstrated.
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- Award ID(s):
- 1710128
- PAR ID:
- 10385242
- Publisher / Repository:
- Optical Society of America
- Date Published:
- Journal Name:
- Optical Materials Express
- Volume:
- 13
- Issue:
- 1
- ISSN:
- 2159-3930
- Format(s):
- Medium: X Size: Article No. 119
- Size(s):
- Article No. 119
- Sponsoring Org:
- National Science Foundation
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