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Compact sources of short pulses with high-repetition-rates are highly desirable for a wide range of applications such as optical coherent tomographic, metrology, optical communication, two photon microscopy, and optical clocks. This thesis is focus on the research and development of fiber lasers that emit short optical pulses. Here we purpose to use Polydimethylsiloxane (PDMS) and SU8-2075 polymers to fabricate thin films doped with SWCNTs that work like a saturable absorber. Moreover, the nonlinear behavior of these films was investigated by using an all-fiber power dependent transmission setup. Using this setup a PDMS/SWCNT film (thickness 200 μm) and SU8-2075 film (thickness 100 μm) were tested. The saturation intensity and the modulation depth of the PDMS/SWCNT and SU8-2075 films are 5.1 MW/cm2, 0.7MW/cm2, 12.3 % and 10 %, respectively. Passively mode-locked Erbium fiber ring lasers have been implemented by using PDMS/SWCNT and SU8-2075 films, the first one produces pulses at a repetition rate of 22.73 MHz with a pulse duration of 1.26 ps assuming a sech2 pulse profile. The second one has a repetition rate of 21.27 MHz with a pulse duration of 871 fs assuming a sech2 pulse profile. A hybrid mode-locked Erbium-doped fiber laser that provides very short pulse-widths while achieving high repetition rates is proposed and experimentally demonstrated. This hybrid configuration is realized by using a PDMS/SWCNT thin film composite as saturable absorber, which is inserted within an active mode-locked laser system using angled connectors. Therefore, the effect of the PDMS/SWCNT composite is to effectively narrow the width of the pulses generated by the active system without modifying its repetition rate. A pulse-width of 730 fs was generated at a repetition rate of 4 GHz, while achieving an average output power of 4 mW. A reduction in the noise of the photodetected RF spectrum was also observed in the hybrid system. Finally, a passively-Q-switching laser has also been built up by using a SU8-2075/SWCNT film. The maximum average power, peak power, and pulse energy were 160 μW, 7.3 mW, and 5.1 nJ, respectively.

El efecto de fuerza foto-electromotriz se ha empleado para determinar amplitudes de vibración (desplazamiento) ocasionadas por una onda ultrasónica al propagarse a través de un material. En el presente trabajo se propone introducir una señal de referencia para cuantificar los desplazamientos. Debido a que van a existir dos señales en el efecto de fuerza fotoelectromotriz, se hace un análisis experimental que consiste en observar el espectro de frecuencias de la señal y compararlo con el espectro de un interferómetro de Mach-Zehnder con dos frecuencias (se modula la fase de cada haz por medio de una señal senoidal). Otros resultados de este análisis son: Se obtienen las curvas que exhiben la relación entre la corriente de la señal del efecto de fuerza foto-electromotriz y la amplitud de modulación para dos moduladores; se observa que estas dos curvas son iguales dentro de los errores experimentales. Además, se muestra experimentalmente que el cociente entre los voltajes de las señales de salida del efecto de fuerza foto-electromotriz son independientes de la intensidad. Por último, se exponen los resultados obtenidos al determinar la amplitud de vibración de una onda ultrasónica al emplear el efecto de fuerza foto-electromotriz con una señal de referencia.