| Summary: | 碩士 === 國立陽明大學 === 放射醫學科學研究所 === 94 === We develop a novel polarimeter based on the properties of linear polarized photon-pairs (LPPP) of which a pair of correlated orthogonal linear polarized photons propagating a common-path in the chiral medium is focused. This results in LPPP able to contribute the detected heterodyne signal coherently and high signal to noise ratio. In this polarimeter, the inherent anti-symmetry of P and S polarization heterodyne signals via polarization rotation of LPPP in chiral medium is derived. Thus, a balanced detector is integrated into this polarimeter that is able to reduce the excess noise of laser intensity fluctuation significantly. Thus, a shot-noise- limited detection of this polarimeter can be achieved. In the mean time, the common phase rejection mode and synchronized detection of this polarimeter further enhance the sensitivity. In this polarimeter, experimentally, the detection sensitivity on circular birefringence of glucose-water solution up to at 10mg/dl is verified. To our knowledge, this is the highest sensitivity ever measured of chiral liquid solution based on single traveling sample cell geometry. Finally, to contrast this method to fiber loop ring-resonator in frequency domain on chiral liquid, an order of 104 is enhanced by this polarimeter compared to theirs. In case of a Fabry-Perot resonance cavity with a multiple reflection mode on sample cell is introduced in this polarimeter, then the sensitivity can be further amplified.
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