scispace - formally typeset
Search or ask a question
Journal ArticleDOI

Passively mode‐locked Nd:glass laser oscillator optimized for TEM00 selectivity and long term stability and reliability

01 Jun 1981-Review of Scientific Instruments (American Institute of Physics)-Vol. 52, Iss: 6, pp 852-857
TL;DR: A passively mode-locked Nd:glass laser oscillator optimized for TEM00 selectivity and long term stability and reliability is presented in this article, where the important aspects of the optimized design are explained in detail and a detailed alignment procedure is also included.
Abstract: A passively mode‐locked Nd:glass laser oscillator optimized for TEM00 selectivity and long term stability and reliability is presented The important aspects of the optimized design are explained in detail A detailed alignment procedure is also included This laser oscillator is capable of producing TEM00, bandwidth‐limited, ≃9 picosecond pulses for ⩾12 hours

Summary (1 min read)

3. Laser Cavity

  • Calculations have demonstrated that TE1~0 0 transverse mode selectivity is strongly dependent on resonator geometry.
  • TEM 00 selectivity, using either diffraction or aperature loss mechanisms, is greatest for a confocal or half-confocal resonator and smallest for a plane-parallel resonator [19] , Although confocal and half-confocal resonators are on the edge of stability [20] , near confocal or near half-confocal resonators are stable resonators and have also displayed more reliable mode-locking than plane-parallel resonators [7] .
  • The optimized laser oscillator cavity is a near half-confocal optical resonator.
  • The front output mirror has a 3 meter radius of curvature and a 60% reflectivity at 1.06 micron.
  • The front mirror's relatively high 60% reflectivity reduces the lasing gain threshold and lowers the energy stored in the Nd:Glass laser rod which minimizes the peak power and many possible detrimental non~linear effects vvhich can spectrally and temporally broaden the mode-locked bandwidth-limited light pulse [22] .

5. Flashlamp Driving Circuit

  • Therefore, after filling the dye solution system with 1,2-dichloroethane, Kodak dye# 9860 is slowly added to the 1,2-dichloroethane until the solution has an optical density of 1.08 + 0,02 at a 1.06 micron wavelength in a 0.5 centimeter spectrophotometric cell.
  • This dye solution should be changed every day, 10-.

7. Oscillator Frame Construction

  • T~1echanical and thermal stability are crucial for long term oscillator reliability and stability.
  • Tnerefore~ the optimized laser oscillator is stabilized by four 1-1/8 inch diametet invar rods [36] .
  • The invar rods feed through .1 1/8' inch holes iin the stainless steel pl After assembly, hm>Jever, the fra1ne is very rigid.
  • Stainless steel set scre11s provide additional stability.

8. Oscillator Frame Connection to the Optics Table

  • For the position close to the dye cell, aperature diameters smaller tilan 2.18 millimeters, e.g. 2.08 millimeters, introduce too much light loss and diameters larger than 2.18 millimeters, e.g. 2.26 millimeters, allow the TEM 01 mode and higher order modes to occur.
  • For aperature positions further from the dye cell, the laser's performance was less reliable.

11. Adjustment for Optimum Lasing Action

  • The voltage threshold is minimized by adjusting the front horizontal differential screw micrometer and observing if the lasing threshold is lowered.
  • The laser oscillator must be operated at its minimum voltage threshold for the most reliable and reproducible laser performance.
  • The front horizontal differential screw adjustment is the only adjustment which should be necessary after initial alignment.

Did you find this useful? Give us your feedback

Content maybe subject to copyright    Report

Lawrence Berkeley National Laboratory
Lawrence Berkeley National Laboratory
Title
A PASSIVELY MODE-LOCKED Nd:GLASS LASER OSCILLATOR OPTIMIZED FOR TEM00
SELECTIVITY AND LONG TERM STABILITY AND RELIABILITY
Permalink
https://escholarship.org/uc/item/04d444z9
Author
George, S.M.
Publication Date
1980-12-01
eScholarship.org Powered by the California Digital Library
University of California

Submitted
to
Review
of
Scientific
Instruments
A
PASSIVELY
MODE-LOCKED
Nd:GLASS
LASER
OSCILLATOR
OPTIMIZED
FOR
TEM
0 0
SELECTIVlTY
AND
LONG
TERM
STABILITY
AND
RELIABILITY
S.M.
George
and
C.B.
Harris
December
1980
TWO-WEEK
LOAN
COPY
This
is
a Library
Circulating
Copy
which
may
be
borrowed
for
two
weeks.
a
personal
retention
copy; call
Tech. Info.
Division;
Ext.
6782.
the
817
LBL-11963
(!,
Preprint

DISCLAIMER
This document was prepared
as
an account
of
work sponsored by the United States
Government. While
this document
is
believed to contain cmTect information, neither the
United States Government nor any agency thereof, nor the Regents
of
the University
of
California, nor any
of
their employees, makes any wananty, express or implied, or
assumes any legal responsibility for the accuracy, completeness, or usefulness
of
any
information, apparatus, product, or process disclosed, or represents that its use would not
infringe privately owned rights. Reference herein to any specific commercial product,
process, or service by
its trade name, trademark, manufacturer, or otherwise, does not
necessarily constitute or imply its
endorsement, recommendation, or favoring by the
United States Government or any agency thereof, or the Regents
of
the University
of
California. The views and opinions
of
authors expressed herein do not necessarily state or
reflect those
of
the United States Govemment or any agency thereof or the Regents
of
the
University
of
California.

Submitted
to
Review
of
Scientific
Instruments
A Passively
Mode-Locked
Nd:Glass
Laser
Oscillator
Optimized for
TEM
00
Selectivity
and
Long
Term
Stabilit~
and
Reliabilit~
S.M.
George
and
C.B.
Harris
Department of
Chemistry
and
t~aterials
and
r,lolecular Research Division
of
Lawrence
Berkeley Laboratory, University
of
California,
Berkeley
California,
94720.
ABSTRACT
A passively mode-locked Nd:Glass
laser
oscillator
optimized
for
TEM
00
selectivity
and
long term
stability
and
reliability
is
presented.
The
important aspects of the optimized design are explained in
detail.
A
detailed
alignment procedure
is
also included. This
laser
oscillator
is
capable of producing
TEM
00
bandwidth-limited. 5 picosecond pulses
for
12
hours.
This manuscript
was
printed
from
originals
provided
by
the author,

"!"
Introduction
sively mode-locked
Nd:Glass
laser
oscillators
are used extensively
as
a
of high
pmver
picosecond
light
pulses
[1].
Limiting
this
laser
oscillator
I
to
tl1e
TEM
00
transverse
mode
is
desirable because the
TEM
00
transverse
mode
produces
a uniform
and
uniphase radial
intensity
profile,
the
smallest
beam
divergence,
and
t
power
density
[2].
Unfortunately, passively
mode~locked
Nd:Glass "lasers
res exclusively to
TEM
00
operation are notoriously unstable,
unreliable
di
cult
to align,
Although
the generation
and
applications of passively mode-locked picosecond
n pulses
has
been
revievved
[3,4]
and
passively mode-locked Nd:Glass picosecond
pt,(lses
have
been
studied
[5,6],
an
optimized,
detailed
design for a
stable,
reliable
and
TEM
00
selective
passively mode-locked Nd:Glass
laser
oscillator
has
never
been
presented, This
is
particularly
unfortunate, because minute
details
can
make
extraordinary differences in the
laser's
performance
[7
.8.9],
Therefore,
~nowledge
of a detailed design
is
extremely important to the user
of
TEM
00
selective,
passively
mode-locked Nd:Glass
lasers.
In
this
paper,
we
report
on
the design. operation,
and
performance of a passively
mode-locked
Nd:Glass
laser
oscillator
which
produces
essentially
bandwidth-limited
5 picosecond pulses
and
has
been
optimized for
TEM
00
selectivity
and
long term
s
ility
and
reliability.
We
discuss the important aspects of the design
in
detail,
with special
emphasis
on
the reasons for the design,
Because
many
of the
design
criteria
are not limited to the passively mode-locked Nd:Glass
laser,
paper should also
be
usefu·l
to
i gners of other
1aser
systems.
In
addition,
we
include a
detailed
alignment procedure because proper alignment
is
critical
for
s
le
9
reliable
and
TEM
00
selective
laser
operation.

Citations
More filters
Journal ArticleDOI
TL;DR: In this paper, the temperature dependence of homogeneous and inhomogeneous vibrational linewidth broadening is reported for the symmetric CH3-stretching vibration in acetonitrile over its entire liquid range at P = 1 atm.
Abstract: The temperature dependence of homogeneous and inhomogeneous vibrational linewidth broadening is reported for the symmetric CH3‐stretching vibration in acetonitrile over its entire liquid range at P=1 atm. A selective excite‐and‐probe vibrational dephasing experiment based on transient stimulated Raman scattering in high laser depletion is used to measure the homogeneous dephasing times T2. The separation of homogeneous and inhomogeneous broadening processes is accomplished using the combined results of isotropic spontaneous Raman studies and selective picosecond vibrational dephasing experiments. As a function of temperature, the relative contributions of homogeneous and inhomogeneous broadening are shown to change significantly in opposing directions. Agreement between experiment and theory supports previous suggestions that homogeneous broadening is caused by rapidly varying processes which affect the vibration via short range repulsive forces. The results also suggest that inhomogeneous broadening is c...

42 citations

Journal ArticleDOI
TL;DR: An active-passive mode-locked Nd:YAG oscillator provides greatly improved shot-to-shot reproducibility compared with passive mode-locking and effects of modulator drive power, laser cavity length, and intracavity etalons on the pulse width and stability are given.
Abstract: An active–passive mode-locked Nd:YAG oscillator provides greatly improved shot-to-shot reproducibility compared with passive mode-locking. Effects of modulator drive power, laser cavity length, and intracavity etalons on the pulse width and stability are given. Using two-photon-fluorescence techniques the pulse width was 35.9 ± 1.7 psec and the corresponding pulse energy was 166 ± 6 μJ.

17 citations

Journal ArticleDOI
TL;DR: In this article, the progress of laser depletion and Stokes growth in transient stimulated Raman scattering (TSRS) was investigated using a Rayleigh-scattering technique, and high laser depletion was found to dominate the behavior of TSRS under conditions relevant to excite-and-probe vibrational dynamics experiments.

3 citations

Journal ArticleDOI
TL;DR: In this article, the role of the resonator parameters in stabilizing the output of passively mode-locked lasers is analyzed, and analytical expressions are derived for the range of optimal values for the radii of curvature of resonator mirrors, and the position of the major elements, for the most commonly used configurations.

2 citations

Journal ArticleDOI
TL;DR: A laminar-flow dye cell with continuously variable thickness (tunable without removal of the dye solution) provides an excellent way of optimizing passively mode-locked lasers.
Abstract: A laminar-flow dye cell with continuously variable thickness (tunable without removal of the dye solution) provides an excellent way of optimizing passively mode-locked lasers. Varying the cell thickness adjusts low-light-level transmittance to match the total cavity and excitation energy conditions and also varies pulse duration. Acceptable cell thicknesses and dye concentrations can be calculated theoretically using well-known parameters. The cell can be conveniently retuned to compensate for dye degradation or to provide conditions for Q switching. Experimental evidence is presented for a Nd:YAG laser.

1 citations

References
More filters
Book
01 Dec 1976
TL;DR: In this article, the characteristics, design, construction and performance of solid-state lasers are discussed from an industrial perspective, focusing on engineering and practical considerations; phenomenological aspects using models are preferred to abstract mathematical derivations.
Abstract: Written from an industrial perspective, this book discusses the characteristics, design, construction and performance of solid-state lasers. Emphasis is placed on engineering and practical considerations; phenomenological aspects using models are preferred to abstract mathematical derivations. This edition has been updated to account for recent developments in the areas of diode-laser pumping, mode locking, ultrashort-pulse generation and other areas.

3,545 citations

BookDOI
01 Jan 1977

408 citations