Approaches to mid-infrared, super-resolution imaging and spectroscopy

Area of Science:

• Optics and Photonics
• Spectroscopy
• Materials Science
• Bioscience

Background:

• Mid-infrared (MIR) spectroscopy provides rich chemical information but is limited by diffraction, hindering high-resolution imaging.
• Existing near-field microscopy techniques face challenges in achieving high spatial resolution for chemical imaging in the MIR fingerprint region.
• There is a need for advanced techniques to overcome the diffraction limit in MIR chemical imaging.

Purpose of the Study:

• To highlight recent advances in super-resolution, mid-infrared (MIR) imaging and spectroscopy.
• To provide an overview of near-field microscopy techniques for high-resolution chemical imaging.
• To detail the infrared photothermal heterodyne imaging (IR-PHI) technique and its applications.

Main Methods:

• Focus on infrared photothermal heterodyne imaging (IR-PHI), a far-field optical technique.
• Description of IR-PHI's practical implementation, including equipment, optical geometries, and contrast mechanisms.
• Review of milestones achieved using IR-PHI in bioscience and materials science.

Main Results:

• IR-PHI enables high spatial resolution chemical imaging in the MIR fingerprint region.
• Demonstrated advances in bioscience and materials science through the application of IR-PHI.
• Summarized key achievements enabled by this super-resolution MIR imaging technique.

Conclusions:

• IR-PHI represents a significant advancement in high-resolution MIR imaging and spectroscopy.
• The technique has shown notable success in driving progress in bioscience and materials science.
• Future outlook points towards more robust and accessible high spatial resolution MIR imaging techniques.