Study on resonance absorption Raman scattering in I 2 liquid-core optical fiber

Abstract

The Raman scattering of I₂ liquid-core optical fiber under the condition of resonance absorption in liquid-core optical fiber is studied in this paper. Iodine is dissolved in transparent benzene to make solution of I₂ in benzene, and the absorption coefficients of the solution are measured at certain wavelengths. The absorption curve can be divided into non-resonance absorption region, pre-resonance absorption region, strict resonance absorption region, and post-resonance absorption region respectively. Resonance absorption Raman scattering experiments are conducted by a 532 nm frequency-doubled Nd:YVO₄ laser, and the wavelength is in the strict resonance absorption region of solution of I₂ in benzene. Compared with I₂, the absorption of benzene can be neglected. Non-resonance Raman scattering of the solution is performed using a 632.8 nm He-Ne laser, and no spectrum lines of I₂ are found. The study demonstrates that there is one spectrum line of I₂ in the Raman scattering spectrum in the I₂ liquid-core optical fiber, but this line is not found in the spectrum of the non-resonance and resonance absorption Raman scattering of I₂ solution in benzene using absorption cell. The experiments proved that I₂ Raman scattering, is greatly enhanced by using both resonance absorption and liquid-core optical fiber.