Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Tip enhanced IR imaging with sub-10 nm resolution and hypersensitivity   IR spectroscopy has been widely used for chemical identification and
quantitative analysis of reactions occurring in a specific time and space
domains by measuring an average signal of the entire system1. Achieving IR
measurements with nanometer-scale spatial resolution is highly desirable to
obtain a detailed understanding of the composition, structure and function of
interfaces2-5. The challenges in IR nanoscopy yet exist owing to the small
molecular cross section and pristine optical diffraction limit. Although atomic
force microscopy (AFM) based techniques, such as scattering-type scanning
near-field optical microscopy and photothermal-induced resonance microscopy
(PTIR), can acquire IR spectroscopy in a few tens of nanometer scale
resolution6-9, IR measurements with monolayer level sensitivity remains elusive
and can only be realized under critical conditions10,11. Herein, we demonstrate
sub-10 nm spatial resolution sampling a volume of ~360 molecules with a strong
field enhancement at the sample-tip junction by implementing noble metal
substrates (Au, Ag, Pt) in photo-induced force microscopy (PiFM). This
technique shows versatility and robustness of PiFM, and is promising for
application in interfacial studies with hypersensitivity and super spatial
resolution.

35
The categories of this paper are: mtrl-th
36
The categories of this paper are: cmp-lg
9
The categories of this paper are: nlin
11
The categories of this paper are: hep-lat
14
The categories of this paper are: math-ph
29
The categories of this paper are: funct-an
4
The categories of this paper are: cond-mat
20
The categories of this paper are: acc-phys
1
The categories of this paper are: cs
31
The categories of this paper are: ao-sci
33
The categories of this paper are: plasm-ph
28
The categories of this paper are: alg-geom
2
The categories of this paper are: math
27
The categories of this paper are: comp-gas
32
The categories of this paper are: atom-ph
6
The categories of this paper are: astro-ph