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Two-dimensional (2D) transition metal carbides and nitrides, commonly known as MXenes, are a class of 2D materials with high free carrier densities, making them highly attractive candidates for plasmonic 2D materials. In this study, we use multiphoton photoemission electron microscopy (nP-PEEM) to directly image the plasmonic near fields of multilayers of the prototypical MXene, Ti3C2Tx, with mixed surface terminations (Tx = F, O, and OH). Photon-energy dependentnP-PEEM reveals a dispersive surface plasmon polariton between 1.4 and 1.9 electron volts on MXene flakes thicker than 30 nanometers and waveguide modes above 1.9 electron volts. Combining experiments with finite-difference time-domain simulations, we reveal the emergence of a visible surface plasmon polariton in MXenes, opening avenues for exploration of polaritonic phenomena in MXenes in the visible portion of the electromagnetic spectrum.
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Polarization-dependent photoemission electron microscopy for domain imaging of inorganic and molecular materials
Polarization-dependent photoemission electron microscopy (PD-PEEM) exploits spatial variation in the optical selection rules of materials to image domain formation and material organization on the nanoscale. In this Perspective, we discuss the mechanism of PD-PEEM that results in the observed image contrast in experiments and provide examples of a wide range of material domain structures that PD-PEEM has been able to elucidate, including molecular and polymer domains, local electronic structure and defect symmetry, (anti)ferroelectricity, and ferromagnetism. In the end, we discuss challenges and new directions that are possible with this tool for probing domain structure in materials, including investigating the formation of transient ordered states, multiferroics, and the influence of molecular and polymer order and disorder on excited state dynamics and charge transport.
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- Award ID(s):
- 2011854
- PAR ID:
- 10590226
- Publisher / Repository:
- American Institute of Physics
- Date Published:
- Journal Name:
- The Journal of Chemical Physics
- Volume:
- 161
- Issue:
- 11
- ISSN:
- 0021-9606
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1063/5.0225765
