NSOM Modes
Reflection NSOM
Reflection NSOM offers the ability to obtain high resolution imaging from opaque samples. To perform effective Reflection NSOM, a clear separation between the excitation path and the collection path is needed. Nanonics cantilevered NSOM probes easily provide for such a separation and allow for easy Reflection mode imaging. Straight NSOM probes or apertured Si probes use the same path for illumination and collection making such measurements nearly impossible.
Reflection NSOM is ideal for mapping the optical properties of grain boundaries on Graphene and other 2D materials. Also, Plasmonics and Photonic devices are often characterized in Reflection NSOM. AFM and NSOM images are simultaneously acquired with the same probe to obtain fully correlated topographic and NSOM data without any need to change the probe.
Speak with an application scientist about how Reflection NSOM can advance your research.
Exemplary Papers
Nano-optical Imaging of Exciton Polaritons Inside WSe2 Waveguides
Fei, et al studied exciton-polaritons in thin 260 nm flakes of WSe2. Using a Nanonics MultiView 4000 NSOM system in Reflection NSOM mode they could directly excite and probe exciton polariton modes by imaging their interference fringes in a method termed "scanning polariton interferometry" at different wavelengths. The near-field illumination allowed for the first time direct excitation and real imaging of the exciton polariton without the need for complicated cavity fabrication. Furthermore, by tuning the excitation laser energy it was possible to map the entire polarity dispersion.
Below: Imaging of the WSe2 thin flake.
Left: Schematics of the near-field optical study of WSe2.
Center and Right: Imaging data of a WSe2 flake (thickness = 260 nm) taken at various excitation wavelengths.
Reference: Z. Fei, M. Scott, D. J. Gosztola, J. J. Foley, J. Yan, D. G. Mandrus, H. Wen, P., Zhou, D. W. Zhang, Y. Sun, J. R. Guest, S. K. Gray, W. Bao, G. P. Wiederrecht1, X., & Xu. (2014). Nano-optical imaging of exciton polaritons inside WSe2 waveguides, 11(7), 152–159.
About the Author: Dr. Zhe Fei is an assistant Professor and Iowa State University. His research interests are in Nanoscale light-matter interactions of novel materials such a two-dimensional layered materials. He has written many papers in the field of plasmons in leading publications as Nature, Nano Letters etc.
Read abstract here: https://arxiv.org/abs/1601.02133
Video
See a Nanonics NSOM Probe
