PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.
This PDF file contains the front matter associated with SPIE Proceedings Volume 8039, including the Title Page, Copyright information, Table of Contents, and the Conference Committee listing.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
Monoclinic crystals of Tm-doped KLu(WO4)2 were used to demonstrate pulsed laser operation near 2 μm. Passive Qswitching
and passive mode-locking were the techniques employed to produce such laser pulses. For passive Qswitching
we used an AlGaAs -based diode laser to pump the active elements and Cr:ZnSe and Cr:ZnS crystals as
saturable absorbers. For passive mode-locking we used a Ti:sapphire laser as pump source and single-walled carbon
nanotubes as saturable absorbers. In the former case, maximum pulse energies of 200 μJ for a pulse duration of 70 ns
were achieved at a repetition rate of 3 kHz with Cr:ZnS saturable absorber, while in the latter case, ultrashort pulse
durations of ~10 ps were measured with a maximum average power of 240 mW. In both laser regimes the oscillation
wavelength was ~1945 nm.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
We report results for high quality transparent ceramic window materials (spinel and β-SiC) and high power solid state
laser materials (Yb:Y2O3 and Yb:Lu2O3). Spinel ceramic demonstrates a record low absorption loss of 6 ppm/cm at 1.06
μm. We also report optical transparency from a β-SiC ceramic fabricated by the Spark Plasma Sintering technique.
Capability of fabricating various shape and size of spinel ceramics is also demonstrated. We report lasing in hot pressed
Yb3+:Y2O3 and
Yb3+:Lu2O3 ceramic made from co-precipitated powder. Highest output power and efficiency from
heavily doped Yb3+ doped Lu2O3 ceramic are reported.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
5 at% Tm-doped NaGd(MoO4)2 laser crystal operated in CW conditions provided up to 641 mW of output power at λ ≈ 1910 nm with a slope efficiency of 50.8% and a pump power laser threshold of 166 mW. 10 at% Tm-doped
Li3Ba2Lu3(MoO4)8 laser operated in quasi-CW conditions provided up to 510 mW of output power at λ ≈ 1950 nm with a
slope efficiency of 71.4% and a pump power laser threshold of 125 mW. Both crystals were grown by the Top Seeded
Solution Growth method at about two hundreds degrees below their melting points. The structural disorder of these
crystals confers inhomogenous broadening to the Tm3+ electronic transitions. Slightly broader laser tuning range and
laser emission bandwidths are observed in the
Li3Ba2Lu3(MoO4)8 crystal despite of the lower expected degree of
crystalline disorder. The crystals are promising for the development of mode locked ultrafast (fs) lasers with emission
close to λ = 2 μm.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
We report what is believed to be the first laser operation based on Ho3+-doped YVO4.
The Ho+3: YVO4 was resonantly diode-pumped at ~1.93 μm to produce up to 1.6 W of continuous
wave (CW) output power at ~2.054 μm. The laser had a slope efficiency of ~38% with respect to
absorbed power. We have measured the absorption and stimulated emission cross sections of The
Ho+3: YVO4 at 77 K and present the calculated gain cross section spectrum at 77 K for different
excited state inversion levels.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
Yb:YAG thin-disk laser performance at room and cryogenic (80K) temperatures is presented. The Yb:YAG gain media,
which is Indium soldered to specialized CuW mounting caps, is cooled using either a pressurized R134A refrigerant
system or by a two-phase liquid nitrogen spray boiler. At cryogenic temperatures spontaneous emission measurements
reveal sharper transition lines and a decrease in the fluorescence lifetime. Lasing reflects that a true four-level laser.
Interchangeable mounting caps allow the same Yb:YAG media to be switched between the two systems. This allows
direct comparison of lasing, amplified spontaneous emission, and temperature performance at 15 °C and at -200 oC.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
New generation of eye safe military applications such as range finding, short range illumination and friend or foe
identification have started to use the 1550nm wavelength region. This was encouraged by the advent of diode lasers
efficient enough to approach the output power of shorter wavelength, 850nm and 905nm devices. This paper will review
the actual performance and technologies of various commercially available 1550nm pulsed laser diodes. The
performance and reliability of a new high brightness 1550nm semiconductor laser diode are disclosed and compared.
Peak power of up to 35 Watts is achieved out of a single junction 350 micron stripe laser. Similarly, peak power in
excess of 20W is achieved with a 180 micron stripe laser. This represents an optical power density of 11.1M W/cm2.
Other key advantages of this new laser are a fast axis FWHM divergence of 25 degrees and less than a 10mRad
divergence after fast axis collimation. The new diode technology will be explained in some detail covering aspects of
design, fabrication and adaptation to meet its final target performances. A description of the optimization of chip
dimensions and laser packaging is also undertaken. Finally, various ideas are offered to further improve the laser
efficiency and power.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
We present breakthrough performance from green and blue InGaN-based laser diodes fabricated on nonpolar/semipolar
substrates. High-power, high-efficiency, and long-lifetime continuous-wave laser operation is demonstrated using these
novel crystal orientations. For green wavelengths at 520 nm, we report on continuous wave single mode lasing with75
mW of output power and wall plug efficiencies over 2.3%. In the blue regime we describe single-mode lasers operating
with over 23% wall plug efficiency and with output powers greater than 750 mW. These InGaN-based direct-diode
lasers offer significant improvement in performance, size, weight, and cost over conventional gas and solid state lasers.
Furthermore, these devices exhibit robust operation over a broad temperature range, can be directly modulated and do
not contain harmful residual infrared radiation typical of second harmonic generation lasers. These characteristics are
salient considerations for such optical devices in battlefield and other security applications.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
Advanced solid state laser architectures place increasingly demanding requirements on high-brightness, low-cost QCW
laser diode pump sources, with custom apertures both for side and end rod pumping configurations. To meet this need, a
new series of scalable QCW pump sources at 808nm and 940nm was developed. The stacks, available in multiple output
formats, allow for custom aperture filling by varying both the length and quantity of stacked laser bars. For these
products, we developed next-generation laser bars based on improved epitaxial wafer designs delivering power densities
of 20W/mm of emission aperture. With >200W of peak QCW power available from a full-length 1cm bar, we have
demonstrated power scaling to over 2kW in 10-bar stacks with 55% wall plug efficiency. We also present the design and
performance of several stack configurations using full-length and reduced-length (mini) bars that demonstrate the
versatility of both the bar and packaging designs. We illustrate how the ROBUST HEAD packaging technology
developed at SCD is capable of accommodating variable bar length, pitch and quantity for custom rod pumping
geometries. The excellent all-around performance of the stacks is supported by reliability data in line with the previously
reported 20 Gshot space-grade qualification of SCD's stacks.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
We describe the successful use of wavefront compensator phaseplates to extend the locking range of VHG-stabilized
diode laser bars by correcting the effects of imperfect source collimation. We first show that smile values of greater than
1μm peak to valley typically limit the achievable wavelength locking range, and that using wavefront compensation to
reduce the effective smile to below 0.5μm allows all emitters to be simultaneously locked, even for bars with standard
facet coatings, operating under conditions where the bar's natural lasing wavelength is over 9nm from the VHG locking
wavelength. We then show that, even under conditions of low smile, wavefront errors can limit the locking range and
locking efficiency, and that these limits can again be overcome by wavefront compensation. This allows wavelength
lock to be maintained over an increased range of diode temperature and drive current, without incurring the efficiency
loss that would be incurred by increasing grating strength. By integrating wavefront compensation into the slow-axis
collimator, we can achieve this high-brightness VHG-optimized beam in a compact optical system.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
We have demonstrated an all-fiber thulium laser system that, without any intracavity polarizing elements or freespace
components, yielded a stable polarization extinction ratio (PER) of ~18 dB. The system is based on singlemode
polarization-maintaining silica fiber and its cavity is formed from each a high and low reflectivity
femtosecond laser written fiber Bragg grating resonant at 2054 nm. The output of the fiber is not only highly
polarized, but maintains a narrow linewidth of 78 pm at its maximum output power of 5.24 W. The high PER
without any polarizing elements in the cavity is of great interest and makes the systems useful for spectral beam
combining and other applications which require polarization dependent optical elements.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
We present theoretical and experimental results of a 130 W continuous-wave (CW), single-frequency, 7 m, polarizationmaintaining
(PM) Yb:doped fiber (25/400) μm amplifier simultaneously seeded with a combination of broadband and
narrow-line signals. Experiments were performed for two thermal configurations and the SBS threshold of the doubly
seeded amplifier is compared to the singly seeded case. In the first configuration, the fiber was wrapped around a cold
spool held at 12° C to diminish thermally induced shifts in the acoustic resonance of the fiber, which is known to
suppress stimulated Brillouin scattering (SBS). In this case, over 80 W of single-frequency output was obtained
demonstrating an enhancement of 3 dB in the SBS threshold compared to the single-tone case whereby the SBS
threshold was 40 W. In the second thermal configuration, 6 m of the fiber is wrapped around the same cold spool, but
approximately 1 m of the fiber is left to cool in ambient conditions. In this case, an optically induced thermal gradient
was formed due to the quantum defect heating associated with power transfer from the pump and broadband seed signals
into the single-frequency signal at the output end of the fiber. Over 130 W of single-frequency output was demonstrated
yielding an effective increase of ~5 dB in the SBS threshold when compared to the single-tone case.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
We describe the generation and amplification of femtosecond pulses at 2-μm wavelength in thulium doped fiber. The
mode-locked oscillator is a ring cavity based on single-mode Tm:fiber producing stable soliton pulses at 70 MHz
repetition rate with 40 pJ pulse energy, centered at ~1.97 μm wavelength with ~8 nm (FWHM) spectral width. These
pulses seed a Tm:fiber based Raman amplifier, which increases the energy up to 9 nJ. The spectrum is broadened up to
40 nm (FWHM) and the center wavelength can be shifted from
~1.97- 2.15 μm. The Raman solitons are inherently
time-bandwidth limited with pulse durations <150 fs.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
We present a Tm:fiber based broadband ASE source which was used for atmospheric CO2 detection. The average
spectral power of this source was limited to ~6.1 μW/nm which was the main limitation in detection of trace
concentrations of gases. This shortcoming was overcome by using an ultrashort pulsed Raman amplifier system with
maximum of ~127 μW/nm of spectral power density which was able to provide sensitivity better than 300 ppm for CO2.
In addition, improving the average power of the ASE provided an essential tool in lab to characterize optical elements
with sharp spectral features around 2 μm.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
TeraDiode has produced ultra-high brightness fiber-coupled direct diode lasers. A fiber-coupled direct diode laser with a
power level of 1,040 W from a 200 μm core diameter, 0.18 numerical aperture (NA) output fiber at a single center
wavelength was demonstrated. This was achieved with a novel beam combining and shaping technique using COTS
diode lasers. The fiber-coupled output corresponds to a Beam Parameter Product (BPP) of 18 mm-mrad and is the lowest
BPP kW-class direct diode laser yet reported. The laser has been used to demonstrate laser cutting and welding of steel
sheet metal up to 6.65 mm thick. Higher brightness fiber-coupled diode lasers, including a module with 418 W of power
coupled to a 100 μm, 0.15 NA fiber, have also been demonstrated.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
We report on the performance of a 100 W, 105μm, 0.17 NA (filled) fiber-coupled module operating at 976 nm. Volume
holographic (Bragg) gratings are used to stabilize the emission spectrum to a 0.2 nm linewidth and wavelengthtemperature
coefficient below 0.01nm/°C with virtually no penalty to the operating power or efficiency of the device.
The typical fiber coupling efficiency for this design is >90%, enabling a rated operating efficiency of ~50%, the highest
reported for a 100W/105μm-class diode pump module (wavelength stabilized or otherwise).
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
Mid-IR Lasers and Mid-IR Fiber Material Development
We present an overview of rare-earth doped heavy metal oxide and oxy-fluoride glasses which show promise as host
materials for lasers operating in the 2-5 μm spectral region for medical, military and sensing applications. By
engineering glass composition and purity, tellurite and germanate glasses can support transmission up to and beyond 5
μm and can have favourable thermal, mechanical and environmental stability compared to fluoride glasses. We discuss
techniques for glass purification and water removal for enhanced infrared transmission. By comparing the material
properties of the glass, and spectroscopic performance of selected rare-earth dopant ions we can identify promising
compositions for fibre and bulk lasers in the mid-infrared. Tellurite glass has recently been demonstrated to be a suitable
host material for efficient and compact lasers in the ~2 μm spectral region in fibre and bulk form and the next challenge
is to extend the operating range further into the infrared region where silica fibre is not sufficiently transparent, and
provide an alternative to fluoride glass and fibre.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
Quantum cascade lasers are finding rapid acceptance in many defense and security applications. Our new multispectral
laser platform providing watt-level outputs near 2.0 μm, 4.0 μm and 4.6 μm in continuous wave regime at room
temperature. Individual lasers are spectrally beam combined into a single output beam with excellent quality. Our
rugged, compact (11 × 10 × 6.5 inches), and highly reliable, air-cooled multispectral laser platform is already finding
acceptance at system level. Our uncooled devices produce > 2W at 4.6 μm and >1.5W at 4.0 μm at room temperature,
and maintain watt-level output at 67°C with real wallplug efficiencies >10%. Finally, all of our QCLs undergo 100-hour
pre-delivery burn-in and pass shock, vibration, and temperature testing according to MIL-STD-810G.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
Laser Material Development: Single Crystalline, Ceramics, Fibers
Transparent sesquioxide ceramics, e.g. Y2O3 and Sc2O3 are being developed as alternatives to yttrium aluminum garnet
(YAG) for high-power solid-state laser systems. In this work, we present the synthesis of these sesquioxide nanopowders
by precipitation techniques and the subsequent processing of these nanopowders into sub-micron transparent ceramics
using a modifying two-step sintering approach. These transparent ceramics exhibited equivalent transparency to that of
analogous single crystals. The microhardness and fracture toughness of the modified two-step sintered ceramic exceeded
those of conventionally sintered ceramic by 25% and 70%, respectively.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
Polycrystalline ceramics offer a number of advantages relative to single crystal materials such as
lower processing temperatures, improved mechanical properties, and higher doping levels with more
uniform distribution of dopants for improved laser performance. Ceramic YAG (Y3Al5O12) and rare earth
sesquioxide (RE2O3) fibers promise to enable a number of high power laser devices via high thermal
conductivity and higher allowable dopant concentration; however, these materials are not currently
available as fine diameter optical-quality fibers. Powder processing approaches for laser quality
polycrystalline ceramic fibers are in development at AFRL. Current processing techniques will be
reviewed. The effects of a number of processing variables on the resulting fibers as well as preliminary
optical characterization will also be presented.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
Laser performance measurements (quasi-CW) were made of various Nd-doped SCHOTT catalog laser glasses: LG-680,
LG-750, LG-760, LG-770, APG-1, and APG-2; all but the first, a silicate, are phosphate glasses. Nominal Nd3+ doping
was approximately 3 × 1020 ions/cm3. An end-pumped, laser diode geometry was used and input powers, pump pulse
length, and pump rep-rates were kept low to avoid thermal lensing (4 W, 1 msec, and 0.1 Hz, respectively). As
expected, the phosphate glasses performed better than the silicate glass. Slope efficiencies ranged from 25% for LG-680
up to nearly 33% for LG-760. APG-1, designed for high rep-rate, high-power systems, performed nearly the same in
this particular configuration as glasses designed for high-energy applications (e.g., LG-770).
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
The noise power spectrum of solid-state lasers - including fiber lasers - exhibits a characteristic peak at the relaxation
oscillation frequency. The tails associated with this peak extend to neighboring spectral ranges and may increase the
noise level above acceptable limits in applications using weak signals. One of the key factors to reduce the relative
intensity noise (RIN) amplitude is a low loss laser resonator. We describe a method to ultimately reduce the intensity
noise in single frequency phosphate fiber lasers by minimizing intra-cavity losses caused by fusion splices between
fibers made of different materials. Conventional fiber Bragg gratings written in silica fibers have been replaced with
gratings written in phosphate glass fibers. The quality of the intra-cavity fusion splice has been improved due to material
similarity. All-phosphate fiber laser devices have been built and tested utilizing the new gratings. The results show
relative intensity noise amplitudes that are very similar to those of conventionally fabricated devices. Challenges in the
grating writing process are currently preventing the new devices from surpassing their commercial counterparts in terms
of performance. However, this type of all phosphate glass fiber lasers may ultimately lead to a new generation of
commercial single frequency fiber lasers with improved intensity noise performance.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
Lasers for Specific Applications and Latest Technology for Laser Functionality
Multiple ground and airborne vehicles could share common and multifunctional laser modules. The host system
constraints and requirements have similarities making a laser modular concept interesting. Among the desired functions,
the core ones are the designation and the rangefinding capabilities. A diode pumped laser source at 1μm with a
switchable OPO stage for wavelength conversion fully satisfies the designation and rangefinding tasks.
Over the last years, CILAS has developed the key technologies for the improvement of the main system parameters with
the imperative constraints to be International Traffic in Arm Regulations Free (ITAR Free). Particularly, this novel
architecture avoids thermo electric cooler (TEC) generally used to stabilise the wavelength of the laser diode pump
source within the entire operational thermal range.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
While conventional Raman Spectroscopy (RS) has predominately used fixed wavelength cw lasers,
advanced Raman spectroscopic techniques such as Stimulated Raman and some types of Raman Imaging
typically need pulsed lasers with sufficient energy to induce the Raman process. In addition, pulsed lasers
are beneficial for the following Raman techniques: Time Resolved Raman (TRR), Resonance Raman (RR),
or non linear Raman techniques, such as Coherent anti-Stokes Raman spectroscopy (CARS). Here the
naturally narrower linewidth of a ns pulse width laser is advantageous to a broader linewidth ultrafast
pulsed laser.
In this paper, we report on the development of a compact, highly efficient, high power solid-state
Ti: Sapphire laser ideally suited for many Raman spectroscopic techniques. This laser produces nanosecond
pulses at kHz repetition rates with a tunable output wavelength from ~1 micron to ~200 nm and pulse
energies up to 1 mJ. The narrow bandwidth of this laser (<0.1cm-1) is ideally suited for applications such as
Laser-induced fluorescence (LIF) measurement of OH free-radicals concentrations, atmospheric LIDAR
and Raman spectroscopy.
New KBBF and RBBF deep ultraviolet (DUV) and vacuum ultraviolet (VUV) crystals are now
available that enable direct doubling of the SHG output of these tunable Ti: Sapphire lasers to directly
achieve wavelengths as short as 175 nm without the need to generate the 3rd harmonic and utilize frequency
mixing. This results in a highly efficient output in the DUV/VUV, enabling improved signal to noise ratios
(S/N) in these previously difficult wavelength regions. Photonics Industries has recently achieved a few
mW of power at 193nm with such direct doubling crystals.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
Precision Photonics Corporation (PPC) has developed high Laser Damage Threshold (LDT) coatings for the important
2-3μm spectral region. Accurate information for both LDT and absorption for such coatings is sparse and often
unreliable, especially when compared to the huge amount of information for these parameters in the 1μm spectral region.
The goal of this effort is to provide useful, accurate information for high power/energy coatings, given the limited LDT
and absorption testing capabilities for the 2-3μm region. In this paper, we present data for 2μm pulsed LDT, 2μm
absorption, 3μm pulsed LDT, and Continuous Wave (CW) LDT data.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
Ultrafast Bandgap Photonics is discussed as an alternative technology for laser-based Directional IR Counter Measures
(DIRCM). Ultra-fast laser is capable of providing fundamentally different type of countermeasure which is able to
counter all generations of heat-seeking missiles. Ultrafast Bandgap Photonic technology is compatible with existing
laser based DIRCM pointing systems as it requires much less energy per pulse and peak power than damage inducing
systems. A foundation of ultra-fast technology is its ability to remotely alter seeker characteristics. In this paper, we will
consider the effects caused by relatively low energy per pulse ultra-fast and, to some extent, fast lasers.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
It is an effective approach to obtain high-power laser output by spectral beam combining (SBC) technologies. The power
of the output beam increases with the increasing of the number of wavelength channels. However, that makes the
traditional SBC system very huge for achieving high power laser output. In this paper, a simple SBC system based on the
superimposed Reflective Volume Bragg Grating (RVBG) is proposed to reduce the scale of the SBC system. Two
structure models of the superimposed RVBG - the superimposed RVBG with the same period and the superimposed
RVBG with different period are analyzed and compared by using the rigorous coupled wave analysis, and their
applications for SBC system are discussed. Numerical results show that the superimposed RVBG are easy to be
fabricated and have the potential to combine multiple lasers with one volume. The superimposed RVBG with different
period can achieve high diffraction efficiency simultaneously for each grating with small slant angle divergence, and is
convenience to combine two beams with small spectral separation.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
A compact micro-oscillator incorporating a dual-bounce, grazing incidence gain module with a folded resonator cavity is
presented. The gain module, previously developed for Nd:YVO4, is embodied in highly doped ceramic Nd:YAG to
generate improved Q-switch performance while maintaining localized pump absorption. The cavity design utilizes a
doubly folded optics path around the gain crystal to increase the intra-cavity mode for a more optimum overlap with the
pump light volume produced by standard lensed laser diode bars. A modified CS-package diode mount is developed to
facilitate the reduced size of the oscillator without sacrificing the ability to use a high-energy, side-pumping
arrangement. The oscillator is combined with a high gain, high energy extraction VHGM amplifier to generate a
transmitter source on the order of 50 mJ. Cooling for both the oscillator and amplifier modules is provided via a
conductive path through the base of the package. Both devices are mounted on opposite sides of a phase-change cooling
reservoir to enable self-contained, burst-mode operation. Beam shaping of the oscillator output, in preparation for
injection into the amplifier, is contained in a small cut-away path on the reservoir side.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
This work demonstrates the modeling process of calculating coupling coefficients of first-order distributed feedback
(DFB) semiconductor lasers, operating on transverse electric modes in the near-infrared (NIR) spectrum range. Optical
waveguides are common structures in semiconductor lasers. The structure has dielectric layers and a metal grating layer.
The interface between the metal layer and its neighboring dielectric layer has a sinusoidal corrugated geometry.
Coupling coefficients are important parameters when analyzing laser performance. To calculate the coupling coefficient
of a shiny-metal-grating waveguide, an electromagnetic model is constructed by truncated Floquet-Bloch formalism
(TFBF). Ray optics technique is also used to calculate the coupling coefficients. These two methods have close results.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.