Work

Multiplicative and subtractive focal volume engineering in coherent Raman microscopy

Year: 2010

Type: article

Abstract: Rigorous calculations are performed to study the effective reduction of the nonlinear excitation volumes when using phase-only masks to condition the pump and Stokes driving fields. Focal volume reduction was achieved using both a multiplicative operation of the excitation fields as well as a subtractive operation. Using a tunable optical bottle beam for the Stokes field, an effective reduction of the width of the excitation volume by a factor of 1.5 can be achieved in the focal plane. Further reduction of the focal volume introduces a rapid growth of sidelobes, which renders such volumes unsuitable for imaging applications. In addition, phase sensitive detection was found to provide information from selective sub-divisions of the engineered coherent anti-Stokes Raman scattering excitation volume. In the case of isolated nanoparticles, an apparent resolution improvement by a factor of 3 is demonstrated, and it is shown that the size of sub-diffraction-limited particles can be accurately determined using phase sensitive detection.

Source: Journal of the Optical Society of America A

DOI: 10.1364/josaa.27.002365

Authors: Varun Raghunathan, Eric Olaf Potma

Institution: University of California, Irvine

Language: English

Topic: Spectroscopy Techniques in Biomedical and Chemical Research

Subfield: Biophysics

Field: Biochemistry, Genetics and Molecular Biology

Domain: Life Sciences

Open Access status: green

Funders: National Science Foundation, National Institute of Biomedical Imaging and Bioengineering, National Center for Research Resources

Awards: A Laser Microbeam Biotechnology Resource, CAREER: Super-resolution in coherent anti-Stokes Raman scattering (CARS) microscopy, A Laser Microbeam Biotechnology Resource