N

nanoindentation

Nanoindentation technique is used to measure the hardness of the sample by exploring the deformation of sample surface intendent by the probe tip.
http://spm.aif.ncsu.edu/nanoindentation/index.html

NF LFM

Near-Field Lorentz Force Microscopy
US Pat. 4992659

NILS

Normalized Image Log Slope
The image log slope multiplied by the nominal feature width.

NPR

Near-Field Photoreflectance Spectroscopy
Appl. Phys. Lett. 78, 2306 (2001).

NSOM

Near field Scanning Optical Microscopy, see SNOM