Dr. Dennis P. Pacheco Profile

Dr. Dennis P. Pacheco

Principal Research Scientist at Physical Sciences Inc

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Publications (17)

Proceedings Article | 27 April 2005 Paper

Efficient tunable near-infrared solid-state dye laser with good beam quality

Jeffrey Russell, Dennis Pacheco, Henry Aldag

Proceedings Volume 5707, (2005) https://doi.org/10.1117/12.601019

KEYWORDS: Dye lasers, Solid state lasers, Semiconductor lasers, Laser damage threshold, Resonators, Diodes, Pulsed laser operation, Tunable lasers, Optical filters, Absorption

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We have demonstrated a laser-pumped, near-infrared solid-state dye laser (SSDL) with a slope efficiency approximately equal to 35%, tunability over approximately equal to 40 nm (from 710 to 750 nm) and M² < 1.3. This device utilizes a folded three-mirror resonator containing a tight focus for the gain medium and a collimated section for the tuning element. The folded cavity is astigmatically compensated through proper choice of sample thickness and cavity fold angle. We achieved low-threshold operation through the tight intracavity focus and by mounting the sample at Brewster’s angle. Two pump lasers were used in this study: (1.) a flashlamp-pumped dye laser (FPDL) with an output wavelength of 630 nm and a pulse duration of approximately equal to 1 microsecond; and (2.) a pulsed red diode laser with an output wavelength of 671 nm and a pulse duration of approximately equal to 200 ns. The gain medium consists of the near-infrared dye Oxazine 725 in the solid host modified PMMA. With the FPDL as the pump source, slope efficiencies up to approximately equal to 35% were measured at the center of the tuning range. A single-plate birefringent filter (BRF) was used to tune the output from approximately equal to 710 to 750 nm with a single output wavelength. The BRF narrowed the spectral output from approximately equal to 15 to approximately equal to 0.8 nm, and provided smooth, continuous tuning over the 40-nm range. Lasing was observed outside this range, but the output consisted of two wavelengths separated by approximately equal to 50 nm (the free spectral range of the BRF). Time-resolved data showed that, for these cases, the laser switches from the shorter to the longer wavelength during the pulse. Input/output curves were generated as a function of resonator feedback for several output wavelengths. Findlay-Clay analyses were used to determine the round-trip cavity loss at each wavelength. The results correlate well with known losses in the resonator, including dye self-absorption losses. Beam-quality measurements were made near the peak of the tuning curve (lambda approximately equal to 727 nm) with a cavity feedback of 95%. At 1.5x threshold, the laser output had an M² value of approximately equal to 1.06. At 7x threshold, the beam quality degraded slightly to M² approximately equal to 1.26. Good temporal tracking was observed between the pump and output pulses, once the SSDL turned on. With design improvements to reduce the threshold, the tunable SSDL was also lased using the diode laser as the pump source. Further characterization of this device under direct diode-pumping is in process.

Proceedings Article | 8 July 2004 Paper

Photophysical properties, photodegradation characteristics, and lasing action for coumarin dye C540A in polymeric media

Guilford Jones, Zhennian Huang, Dennis Pacheco, Jeffrey Russell

Proceedings Volume 5332, (2004) https://doi.org/10.1117/12.534251

KEYWORDS: Polymers, Dye lasers, Polymethylmethacrylate, Photolysis, Solids, Pulsed laser operation, Luminescence, Absorption, Solid state lasers, Quantum efficiency

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Proceedings Article | 8 July 2004 Paper

Solid state dye lasers pumped directly by diode lasers

Dennis Pacheco, William Russell, Henry Aldag

Proceedings Volume 5332, (2004) https://doi.org/10.1117/12.531233

KEYWORDS: Dye lasers, Solid state lasers, Solid state physics, Semiconductor lasers, Diodes, Resonators, Pulsed laser operation, Polymethylmethacrylate, Solids, Laser damage threshold

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Proceedings Article | 18 June 2004 Paper

Spatially and temporally resolved transmission measurements on novel high-damage-threshold polymer optical limiting devices

Gami Maislin, Dennis Pacheco, Aimee Rose, William Russell, Mitchell Zakin

Proceedings Volume 5351, (2004) https://doi.org/10.1117/12.529020

KEYWORDS: Polymers, Optical limiting, Q switched lasers, Charge-coupled devices, Polymethylmethacrylate, Physical sciences, Solid state electronics, Nd:YAG lasers, Solid state lasers, Absorption

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Proceedings Article | 10 June 2004 Paper

Innovative laser-hardened solid host material for nonlinear filters

Dennis Pacheco, William Russell, Henry Aldag, Barry DeCristofano, Masato Nakashima, Brian Kimball

Proceedings Volume 5273, (2004) https://doi.org/10.1117/12.524526

KEYWORDS: Glasses, Polymers, Solids, Nonlinear filtering, Laser damage threshold, Laser induced damage, Solid state physics, Solid state lasers, Liquids, Dye lasers

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Proceedings Article | 17 June 2003 Paper

Fluorescence and lasing properties of meso-substituted benzo-fused pyrromethene dyes in solid host media

Guilford Jones, Zhennian Huang, Dennis Pacheco

Proceedings Volume 4968, (2003) https://doi.org/10.1117/12.479552

KEYWORDS: Solids, Absorption, Luminescence, Polymerization, Polymethylmethacrylate, Dysprosium, Dye lasers, Liquids, Quantum efficiency, Oxidation

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Proceedings Article | 17 June 2003 Paper

Characterization and performance of pulsed red diode lasers for pumping dye lasers

Dennis Pacheco, William Russell, Jeffrey Russell, Richard Tilton, Michael Reilly, Henry Aldag

Proceedings Volume 4968, (2003) https://doi.org/10.1117/12.479553

KEYWORDS: Dye lasers, Semiconductor lasers, Diodes, Laser damage threshold, Solid state lasers, Resonators, Solid state physics, Solids, Pulsed laser operation, Liquids

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Proceedings Article | 13 March 2002 Paper

Fluorescence and lasing properties of benzo-fused pyrromethene dyes in polymethyl methacrylate solid host media

Guilford Jones, Zhennian Huang, Satish Kumar, Dennis Pacheco

Proceedings Volume 4630, (2002) https://doi.org/10.1117/12.459008

KEYWORDS: Solids, Luminescence, Quantum efficiency, Diodes, Dye lasers, Liquids, Polymethylmethacrylate, Near infrared, Rhodamine, Polymerization

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Proceedings Article | 13 March 2002 Paper

Laser threshold and efficiency measurements of solid state dye lasers operating in the near-infrared under microsecond pumping

Jeffrey Russell, Dennis Pacheco, William Russell, Henry Aldag, Alexander Manenkov

Proceedings Volume 4630, (2002) https://doi.org/10.1117/12.459006

KEYWORDS: Laser damage threshold, Solid state lasers, Solid state physics, Dye lasers, Rhodamine, Optical pumping, Pulsed laser operation, Semiconductor lasers, Solids, Dysprosium

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Proceedings Article | 16 April 2001 Paper

Photochemical and lasing properties of pyrromethene dyes

Guilford Jones, Oksana Klueva, Satish Kumar, Dennis Pacheco

Proceedings Volume 4267, (2001) https://doi.org/10.1117/12.424614

KEYWORDS: Phase modulation, Oxygen, Photolysis, Absorption, Bioalcohols, Dysprosium, Optical filters, Liquids, Dye lasers, Oxidation

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Proceedings Article | 16 April 2001 Paper

Beam-quality measurements on solid state dye lasers using nonconfocal unstable resonators

Jeffrey Russell, Dennis Pacheco, Henry Aldag, S. Dolotov, M. Koldunov, Ya. Kravchenko, Alexander Manenkov, A. Reznichenko, G. Roskova

Proceedings Volume 4267, (2001) https://doi.org/10.1117/12.424615

KEYWORDS: Resonators, Mirrors, Dye lasers, Output couplers, Solid state lasers, Diagnostics, Polymethylmethacrylate, Polymers, Glasses, Solid state physics

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Proceedings Article | 14 April 2000 Paper

Efficient solid state dye lasers based on polymer-filled microporous glass

Henry Aldag, S. Dolotov, M. Koldunov, Ya. Kravchenko, Alexander Manenkov, Dennis Pacheco, A. Reznichenko, G. Roskova

Proceedings Volume 3929, (2000) https://doi.org/10.1117/12.382758

KEYWORDS: Phase modulation, Glasses, Polymers, Dye lasers, Rhodamine, Information operations, Energy efficiency, Solid state lasers, Polymethylmethacrylate, Rhodium

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Proceedings Article | 27 May 1998 Paper

Fluorescence and lasing properties of pyrromethene dyes in epoxy solid host media

Guilford Jones, Oksana Klueva, Sandra Linares-Samaniego, Dennis Pacheco

Proceedings Volume 3265, (1998) https://doi.org/10.1117/12.308692

KEYWORDS: Epoxies, Phase modulation, Luminescence, Solids, Polymers, Quantum efficiency, Laser damage threshold, Dye lasers, Solid state lasers, Solid state physics

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Proceedings Article | 27 May 1998 Paper

Ultrashort-pulse generation in solid state dye lasers

Serge Garnov, Sergei Klimentov, Ya. Kravchenko, Alexander Manenkov, Dennis Pacheco, Henry Aldag

Proceedings Volume 3265, (1998) https://doi.org/10.1117/12.308690

KEYWORDS: Picosecond phenomena, Polymers, Laser resonators, Dye lasers, Chemical elements, Solid state lasers, Mode locking, Solid state physics, Mirrors, Nd:YAG lasers

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Proceedings Article | 27 May 1998 Paper

Comparison of the laser performance of solid state dye media under long- and short-pulse excitation

Dennis Pacheco, Henry Aldag

Proceedings Volume 3265, (1998) https://doi.org/10.1117/12.308657

KEYWORDS: Epoxies, Phase modulation, Polymethylmethacrylate, Dye lasers, Laser damage threshold, Solids, Solid state lasers, Energy efficiency, Solid state physics, Absorption

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Proceedings Article | 31 March 1997 Paper

New high-efficiency pyrromethene-580-doped modified PMMA solid state dye laser

Ya. Kravchenko, Alexander Manenkov, G. Matushin, Vitaly Mizin, Dennis Pacheco, Henry Aldag

Proceedings Volume 2986, (1997) https://doi.org/10.1117/12.269988

KEYWORDS: Polymers, Polymethylmethacrylate, Laser induced damage, Pulsed laser operation, Absorption, Dye lasers, Solid state lasers, Laser damage threshold, Solid state physics, Resonators

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Proceedings Article | 25 March 1996 Paper

Performance of a flashlamp-pumped solid state dye laser

Stephen Minnigh, Dennis Pacheco, James Burke, Paul Dunleavy, Henry Aldag, John Ehrlich

Proceedings Volume 2698, (1996) https://doi.org/10.1117/12.236175

KEYWORDS: Polymers, Liquids, Polymethylmethacrylate, Resonators, Dye lasers, Solid state lasers, Solid state physics, Energy efficiency, Solids, Pulsed laser operation

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Showing 5 of 17 publications

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