This
experiment
teaches the fundametals of nonlinear optics and the use
of the Coherent Antistokes Raman response as one example of
corresponding
spectroscopic applications. CARS is the coherent version of the
spontaneous inelastic Raman emission.
With the advent of ultrashort laser pulses it has found renewed
attention for
chemically specific imaging and microscopy.
A
few
words about CARS
history:
Maker and Terhune, when at the
laboratories of Ford Motor Company, first investigated the nonlinear
Raman
process in greater detail (Phys. Rev. 137,
A801
(1965)).
Several years later, the term CARS was introduced (Appl. Phys. Lett. 25,
387 (1974). CARS has since found widespread applications for
vibrational spectroscopy of
molecules and solids. After its first demonstration by Duncan (Opt.
Lett. (1982)) it was not until 1999, that the full potential of CARS
for highly-sensitive 3D
microscopic imaging was demonstrated. Largely pioneered by Sunny
Xie's
group
at Harvard, CARS microscopy
allows for the in situ
investigation of
elementary biochemical processes in living cells.