Amauri Agostinho Ferreira - Academia.edu (original) (raw)
Uploads
Papers by Amauri Agostinho Ferreira
For high resolution spectroscopy, a high power, stable line output laser is desirable for pumping... more For high resolution spectroscopy, a high power, stable line output laser is desirable for pumping different types of optical parametric oscillator resonators (OPO). Single-frequency lasers are in the range of 10 watts of output power, while, depending on the application and the OPO type, higher power (> 20 W) is desirable. In this work a single frequency high power laser based on diode pumping modules with Nd:YAG as the active medium was developed. Two Nd:YAG bars transversally pumped by diodes were used in a configuration of a CW polarized ring resonator with beam quality TEM 00 and output power of 105,2 W. The output power achieved is, to our knowledge, the highest for continuous polarized fundamental mode ring lasers using standard Nd:YAG modules with side pumping. The resonator allowed the tuning power in a large dynamic range and obtained excellent beam quality using a half-wave plate between the two rods for birefringence compensation. The single frequency operation was achieved using a TGG (Terbium Gallium Garnet) crystal, two magnets and an etalon, with an output power of 51.60 W and a 17 MHz full width at half maximum (FWHM) spectral width.
We discuss the challenge high school teachers face when teaching physics to the blind. Using the ... more We discuss the challenge high school teachers face when teaching physics to the blind. Using the oral history method, we interview physics teachers who have dealt with the inclusion of blind students in regular classrooms. Based on our study, we find that the performance of these students varies, depending on the studied subject. The narrative makes clear the teachers' lack
For high resolution spectroscopy, a high power, stable line output laser is desirable for pumping... more For high resolution spectroscopy, a high power, stable line output laser is desirable for pumping different types of optical parametric oscillator resonators (OPO). Single-frequency lasers are in the range of 10 watts of output power, while, depending on the application and the OPO type, higher power (> 20 W) is desirable. In this work a single frequency high power laser based on diode pumping modules with Nd:YAG as the active medium was developed. Two Nd:YAG bars transversally pumped by diodes were used in a configuration of a CW polarized ring resonator with beam quality TEM 00 and output power of 105,2 W. The output power achieved is, to our knowledge, the highest for continuous polarized fundamental mode ring lasers using standard Nd:YAG modules with side pumping. The resonator allowed the tuning power in a large dynamic range and obtained excellent beam quality using a half-wave plate between the two rods for birefringence compensation. The single frequency operation was achieved using a TGG (Terbium Gallium Garnet) crystal, two magnets and an etalon, with an output power of 51.60 W and a 17 MHz full width at half maximum (FWHM) spectral width.
We discuss the challenge high school teachers face when teaching physics to the blind. Using the ... more We discuss the challenge high school teachers face when teaching physics to the blind. Using the oral history method, we interview physics teachers who have dealt with the inclusion of blind students in regular classrooms. Based on our study, we find that the performance of these students varies, depending on the studied subject. The narrative makes clear the teachers' lack