The emphasis of this work has been in two areas of optical materials - the crystal-chemical development of new optical frequency converters and the synthesis and study of new hosts for Cr����� luminescence and lasing. A simple method has been developed to identify promising frequency-doubling materials containing triangular oxoanions by estimation of nonlinear susceptibilities. Implementation of this method and its results have generated predictive capabilities in determining the relationships among crystal structure, nonlinear properties, and threshold powers. The new noncentrosymmetric borate SrLiB���O������ is discussed; its structure is built from a 3-dimensional condensation of B���0��� units with channels alternately filled with Sr and Li atoms. From these studies, a prescription for new pyroborate frequency converters has been developed. The material CdC������C���H7NO���, has been synthesized and structurally characterized by single-ciystal X-ray diffraction. Three new alkaline-earth beryllium borates, built from unique 2- and 3- dimensional networks and frameworks, have been identified. The structure of SrBe���(B0���)��� consists of layers of composition [Be���(BO���)���] interleaved by Sr atoms. CaBeB���O��� is constructed from a Ca0��� polyhedral network and a beryllium borate network. In BaBe���(B0���)��� the structure is composed of a beryllium borate framework intermingled with a Ba-centered dodecahedral framework. Several materials with potential as hosts for Cr����� lasing have been analyzed. The structural study of the laser host LiSrAIF6 revealed the distortions at the Al site that contribute to the unique optical properties of the Cr����� -doped crystals. The family of solid state oxide A���MM'(B0���)��� is one of the largest families of oxide reported to date. Metal site preferences, disorder, solid solubility, and the interrelationship between this structure and the layered structure type of Ba���Sc(B0���)��� are detailed. An optimal synthetic procedure has been developed for these materials to provide pure, highly crystalline phases. Also, the structural and optical features of (Cr�����:) Sr���In(B0���)��� with A= Sr and M=M'= In have been studied. The material Sr���LilnB���O������, was discovered while searching for a suitable lithium borate flux for crystal growth of the compound Sr���In(B0���)���. / Graduation date: 1993

Thesis (M.S.)--West Virginia University, 2004. / Title from document title page. Document formatted into pages; contains xi, 121 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 106-107).

High power diode-pumped solid state (DPSS) lasers are a rapidly growing technology that is attractive for various applications in scientific and industrial fields. DPSS lasers are highly efficient, reliable and durable with superior beam quality when compared to flash-lamp pumped lasers. Double-tungstate crystals such as potassium yttrium tungstate Yb:KY(WO₄)₂ (Yb:KYW) are one of the most popular active materials used in DPSS lasers for generation of continuous wave radiation and ultrashort (i.e. femtosecond, 10⁻¹⁵ s) pulses with high average output power. The high pump power of laser diodes results in considerable heat generation in a laser crystal that in turn causes thermal lensing effect. Thermal lensing affects the performance and stability of a resonator, and plays an important role in limiting the output power and degrading the beam quality of solid state lasers. Despite these facts, no detailed studies of thermal effects in Yb:KYW lasers were reported to date. In this work thermal lensing in a diode-pumped Ng-cut Yb:KYW laser operating at the wavelength of 1.04 μm was characterized. A maximum output power of 3.5 W with a nearly diffraction limited output beam (M₂ < 1.2) was achieved under the absorbed pump power of 13.8 W. The focal lengths of the induced thermal lenses were obtained from the laser output beam size measurements at various incident pump power levels and ABCD matrix analysis. At maximum output power the focal length of the induced thermal lens was found to be 814 mm for the Nm direction (horizontal) and 144 mm for the Np direction (vertical). Thermal lens sensitivity factors were 1.26 m⁻¹/W and 0.32 m⁻¹/W for the Np and Nm directions, respectively. This highly astigmatic thermal lensing can be explained by strong anisotropy of thermo-optical properties of the crystal and its cooling geometry. In addition, the finite element analysis (FEA) method was employed to obtain the focal lengths of the induced thermal lens inside the crystal. Simulation results obtained from the theoretical model were compared to experimental data, and the accuracy of the model was verified. The results of this work are critical for practical design of the efficient and reliable Yb:KYW lasers with multi-Watt average output power.

High power diode-pumped solid state (DPSS) lasers are a rapidly growing technology that is attractive for various applications in scientific and industrial fields. DPSS lasers are highly efficient, reliable and durable with superior beam quality when compared to flash-lamp pumped lasers. Double-tungstate crystals such as potassium yttrium tungstate Yb:KY(WO₄)₂ (Yb:KYW) are one of the most popular active materials used in DPSS lasers for generation of continuous wave radiation and ultrashort (i.e. femtosecond, 10⁻¹⁵ s) pulses with high average output power. The high pump power of laser diodes results in considerable heat generation in a laser crystal that in turn causes thermal lensing effect. Thermal lensing affects the performance and stability of a resonator, and plays an important role in limiting the output power and degrading the beam quality of solid state lasers. Despite these facts, no detailed studies of thermal effects in Yb:KYW lasers were reported to date. In this work thermal lensing in a diode-pumped Ng-cut Yb:KYW laser operating at the wavelength of 1.04 μm was characterized. A maximum output power of 3.5 W with a nearly diffraction limited output beam (M₂ < 1.2) was achieved under the absorbed pump power of 13.8 W. The focal lengths of the induced thermal lenses were obtained from the laser output beam size measurements at various incident pump power levels and ABCD matrix analysis. At maximum output power the focal length of the induced thermal lens was found to be 814 mm for the Nm direction (horizontal) and 144 mm for the Np direction (vertical). Thermal lens sensitivity factors were 1.26 m⁻¹/W and 0.32 m⁻¹/W for the Np and Nm directions, respectively. This highly astigmatic thermal lensing can be explained by strong anisotropy of thermo-optical properties of the crystal and its cooling geometry. In addition, the finite element analysis (FEA) method was employed to obtain the focal lengths of the induced thermal lens inside the crystal. Simulation results obtained from the theoretical model were compared to experimental data, and the accuracy of the model was verified. The results of this work are critical for practical design of the efficient and reliable Yb:KYW lasers with multi-Watt average output power.

Thesis (Ph.D.) - University of St Andrews, March 2007.

Thesis (M.S. in Applied Physics and M.S. in Electrical Engineering)--Naval Postgraduate School, December 2002. / Thesis advisor(s): William B. Colson, Phillip E. Pace. "AD-A411 177." Includes bibliographical references (p. 81-83). Also available online.

Thesis (M.S. in Applied Physics and M.S. in Electrical Engineering)--Naval Postgraduate School, December 2002. / Thesis advisor(s): William B. Colson, Phillip E. Pace. Includes bibliographical references (p. 81-83). Also available online.

Thesis (M.S. in Applied Physics and M.S. in Electrical Engineering)--Naval Postgraduate School, December 2002. / Thesis advisor(s): William B. Colson, Phillip E. Pace. Includes bibliographical references (p. 101-102). Also available online.

Made available in DSpace on 2014-10-09T12:28:51Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:57:06Z (GMT). No. of bitstreams: 0 / Dissertacao (Mestrado Profissionalizante em Lasers em Odontologia) / IPEN/D-MPLO / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP; Faculdade de Odontologia, Universidade de Sao Paulo, Sao Paulo

The advent of new quasi phase matched materials and high spectral/spatial quality pump sources has led to a renaissance in the development of continuous-wave optical parametric oscillators for the coherent generation of broadly tunable light in the mid infrared spectral region. This thesis describes a novel technique which overcomes the threshold constraints of the singly resonant oscillator (SRO) and stability constraints of the doubly resonant oscillator (DRO) traditionally associated with these devices by placing a singly resonant optical parametric oscillator in the high circulating field found within the cavity of a laser: the intracavity optical parametric oscillator. An SRO based upon the nonlinear material periodically poled LiNb03 (PPLN) operating internal to an all solid state, 1W diode pumped Nd:YV04 mini-laser is demonstrated and characterised. This system exhibits SRO threshold at only 330mW of external diode pump power, and produced a total of 70mW of extractable idler at 1W diode pump power. Through multi-parameter tuning of the poled nonlinear material we demonstrate broad tuning of the non-resonant idler through the spectrally important range 3.1 - 4μm. Novel cavity design desensitises the system to the effects of thermal lensing in the nonlinear medium, resulting in stable spatial and mean power outputs. The short term pump field stability is characterised by intensity modulation brought about by the onset of relaxation oscillations ; a consequence of placing the SRO within the cavity of the pump laser. A comparative study of SRO's based upon PPLN and the new material periodically poled RbTi0As04 (PPRTA) pumped internal to a high power fibre coupled diode pumped Nd:YV04 laser cavity is undertaken and presented. We see that although the nonlinearity and interaction length of the PPRTA is smaller than that of PPLN, the system based upon PPRTA outperforms or is at least comparable with that based upon PPLN in every respect with the exception of idler tuning range. We attribute this to the reduced sensitivity of this material to the effect of thermal lensing. Up to 440mW of extracted idler was produced by each system. The reduction of interferometric feedback of the pump field by the signal cavity mirror was found to eliminate the onset of relaxation oscillations in the case of PPRTA but not PPLN, due to thermal air currents dominating the triggering process in iii this system. Recently published Sellmeier equations and temperature derivatives for PPRTA are compared with the experimentally observed temperature tuning behaviour. The inclusion of an optical parametric oscillator within the cavity of the pump laser impacts significantly upon the transient dynamics of the pump laser in which it resides. We show experimental evidence of this effect and outline a strategy to minimise the effects of relaxation oscillations in the context of a simple numerical model which shall be derived. Possible future avenues of research are discussed in the context of the results and conclusions obtained over the course of this research program.