Accession Number : ADA582423


Title :   Mirrorless Lasing in Optically Pumped Rubidium Vapor


Descriptive Note : Master's thesis


Corporate Author : AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH GRADUATE SCHOOL OF ENGINEERING AND MANAGEMENT


Personal Author(s) : Richards, Ryan M


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a582423.pdf


Report Date : Mar 2013


Pagination or Media Count : 55


Abstract : Mirrorless lasing has been successfully demonstrated in a Rubidium heat pipe. Lasing was observed on the 6(2)P(sub 3/2)-6(2)S(sub 1/2) energy transition at 2.73 microns and on the 6(2)P(sub 1/2)-6(2)S(sub 1/2) transition at 2.79 microns. The transitions were optically pumped from 5(2)S(sub 1/2)-6(2)P(sub 3/2) at 420.2 nm and from 5(2)S(sub 1/2)-6(2)P(sub 1/2) at 421.7 nm, respectively. The 5(2)S(sub 1/2)-6(2)P(sub 3/2) transition was excited over a 36 GHz band, while the 5(2)S(sub 1/2)-6(2)P(sub 1/2) transition was excited over a 24 GHz band. Both pump transitions showed a high degree of saturation and only a small fraction (1%) of the incident pump energy was absorbed. Output energies of up to 5 nJ were obtained at 2.73 microns and of up to 5.4 nJ at 2.79 microns when pumped at pulse energies of 4 mJ. Both transitions experienced bleaching at this 4 mJ pump energy, limiting further IR output energy. Increasing rubidium concentration at bleached pump energies showed no increase in laser energy after 170 deg. C, likely due to second order processes. Slope efficiency for both transitions, however, increased linearly with rubidium concentration up to 11 x .000001 The addition of small amounts of argon, helium, and ethane (5-45 Torr) were found to fully quench lasing action on both transitions.


Descriptors :   *GAS LASERS , *OPTICAL PUMPING , *RUBIDIUM , *VAPORS , ABSORPTION , ENERGY TRANSFER , EXCITATION , GROUND STATE , HEAT PIPES , LASER APPLICATIONS , OUTPUT , QUENCHING , SATURATION , THESES , TRANSITIONS


Subject Categories : Lasers and Masers


Distribution Statement : APPROVED FOR PUBLIC RELEASE