Vector FWM in optical fibers: tuning techniques and applications

• Autores: A. Loredo Trejo
• Directores de la Tesis: Antonio Diez Cremades (dir. tes.)
• Lectura: En la Universitat de València ( España ) en 2022
• Idioma: inglés
• Tribunal Calificador de la Tesis: Miguel Vicente Andrés Bou (presid.), Rosa Ana Pérez Herrera (secret.), Gaizka Durana Apaolaza (voc.)
• Programa de doctorado: Programa de Doctorado en Física por la Universitat de València (Estudi General)
• Materias:
  • Física
• Enlaces
  • Tesis en acceso abierto en: TESEO
• Resumen

  • Recently, the nonlinear four-wave mixing (FWM) effect in optical fibers has attracted great interest for the development of new optical fiber light sources due to the multiple light emission produced by this nonlinear effect. In recent years, such FWM-based light sources have demonstrated great utility in areas such as quantum optics and advanced Raman-based microscopy. Additionally, according to the polarization state of the pump light responsible for the FWM effect and the birefringence of the fiber, the light produced by FWM can exhibit different polarization properties given the vector nature of the FWM. Thus, this enables the design and development of polarized light sources with multiple emission which can be of great interest in different studies or applications of photonics. In addition, FWM effect is relatively sensitive to changes in the optical properties of the medium in which it is generated. In the case of an optical fiber, the chromatic dispersion and birefringence of the fiber are the most relevant parameters in the phase-matching condition of FWM. In such a way, certain physical quantities can be measured by means of FWM-based fiber optic sensors taking advantage of the susceptibility of the fiber to changes in the optical properties of the fiber itself. In this thesis we provide the theoretical and experimental study of vector FWM produced in weakly birefringent optical fibers. In particular, we have focused our attention on a specific process of vector FWM known as polarization modulation instability (PMI). In this work we provide simple and practical methods to generate and tune the emission of intense bands of light produced by PMI/FWM over a wide wavelength range.

    Given the high efficiency of microstructured optical fibers (MOFs) to generate nonlinear effects such as FWM, most of our experiments were carried out with MOFs with different guiding properties. In this work, we show the generation of PMI/FWM in fibers with ANDi dispersion profiles, fibers with 1 or 2 zero-dispersion wavelength, and hybrid MOFs infiltrated with optical liquids whose properties enables PMI/FWM generation and tuning.

    In this thesis we have demonstrated broadband tuning of intense light bands produced by PMI. Tunability is achieved by exploiting the sensitivity of the PMI phase-matching condition to changes of dispersion and birefringence of the optical fiber. To this end, simple techniques have been employed to control fiber dispersion and birefringence based on either the elasto-optic effect of fused silica or the thermo-optic effect of the liquids infiltrated into the fibers. In addition, simultaneous generation and tuning of FWM and PMI in MOFs has been demonstrated for the first time. This required a fine control of the optical guiding properties of the fibers. In this study we have experimentally demonstrated tunability of the light bands generated by both effects over a wide wavelength range, covering a large part of the near-infrared spectrum.