Phys. org November 1, 2018
Researchers in Singapore have developed a method that allows changes in the infrared beam to be analyzed via the visible beam, it provides more information than conventional spectroscopy. They fed laser light into a lithium niobate crystal that split some of the laser photons into two quantum-linked photons of lower energies through parametric down-conversion, one in the infrared, and one in the visible parts of the spectrum. When the original laser beam re-entered the crystal, it created a new pair of down-converted beams that interfered with the light created in the first pass. A sample is placed in the infrared beam affected the interference between first-pass and second-pass beams, which could be detected in both the infrared and visible beams. In tests they were able to gain more information about the sample. The technique has applications in medical and material testing…read more. Open Access TECHNICAL ARTICLE 1 , 2 ,
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