Spectral control of power diode lasers with enhanced output by an external cavity based on a volume holographic grating
To achieve the maximum efficiency in the single-frequency lasing mode of a laser diode with an external cavity, it is necessary to minimize losses in the optical system for the output beam and to provide the optimal frequency-selective feedback. In this paper, we have investigated the scheme of an e...
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Інститут фізики напівпровідників імені В.Є. Лашкарьова НАН України
2018
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| Cite this: | Spectral control of power diode lasers with enhanced output by an external cavity based on a volume holographic grating / S.M. Bashchenko, L.S. Marchenko, A.M. Negriyko, T.N. Smirnova, I.V. Matsnev // Semiconductor Physics Quantum Electronics & Optoelectronics. — 2018. — Т. 21, № 4. — С. 424-428. — Бібліогр.: 13 назв. — англ. |
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| author | Bashchenko, S.M. Marchenko, L.S. Negriyko, A.M. Smirnova, T.N. Matsnev, I.V. |
| author_facet | Bashchenko, S.M. Marchenko, L.S. Negriyko, A.M. Smirnova, T.N. Matsnev, I.V. |
| citation_txt | Spectral control of power diode lasers with enhanced output by an external cavity based on a volume holographic grating / S.M. Bashchenko, L.S. Marchenko, A.M. Negriyko, T.N. Smirnova, I.V. Matsnev // Semiconductor Physics Quantum Electronics & Optoelectronics. — 2018. — Т. 21, № 4. — С. 424-428. — Бібліогр.: 13 назв. — англ. |
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| container_title | Semiconductor Physics Quantum Electronics & Optoelectronics |
| description | To achieve the maximum efficiency in the single-frequency lasing mode of a laser diode with an external cavity, it is necessary to minimize losses in the optical system for the output beam and to provide the optimal frequency-selective feedback. In this paper, we have investigated the scheme of an external cavity diode laser (ECDL) based on a phase volume holographic grating (VHG). Angular and spectral selectivities of the holographic grating allow for adjusting the optical feedback with low losses in the cavity, and it can be used for the frequency narrowing of diode-array bars. Here, the optimal parameters of VHG and the temperature dependence of the diode laser bar spectrum have been studied, and the proposals on VHG design have been developed.
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ISSN 1560-8034, 1605-6582 (On-line), SPQEO, 2018. V. 21, N 4. P. 424-428.
© 2018, V. Lashkaryov Institute of Semiconductor Physics, National Academy of Sciences of Ukraine
424
Optoelectronics and optoelectronic devices
Spectral control of powerful diode lasers with enhanced output
by external cavity based on volume holographic grating
S.M. Bashchenko, L.S. Marchenko, A.M. Negriyko, T.N. Smirnova, I.V. Matsnev
Institute of Physics National Academy of Sciences of Ukraine
46, prospect Nauky, 03680 Kyiv, Ukraine
Abstract. To achieve the maximum efficiency in single-frequency lasing mode of laser
diode with external cavity, it is necessary to minimize losses in the optical system for the
output beam and to provide the optimal frequency-selective feedback. In this paper, we
have investigated the scheme of an external cavity diode laser (ECDL) based on phase
volume holographic grating (VHG). Angular and spectral selectivities of the holographic
grating allow to adjust the optical feedback with low losses in the cavity, and it can be used
for the frequency narrowing of diode-array bars. Here, the optimal parameters of VHG and
the temperature dependence of the diode laser bar spectrum have been studied, and the
proposals on VHG design have been developed.
Keywords: diode laser, spectrum, temperature, external cavity, volume holographic
grating.
doi: https://doi.org/10.15407/spqeo21.04.424
PACS 42.40.Eq, 42.55.Px, 42.60.Da
Manuscript received 05.11.18; revised version received 25.11.18; accepted for publication
29.11.18; published online 03.12.18.
1. Introduction
To control of laser diodes radiation spectrum is important
for many laser applications, namely: laser spectroscopy,
laser cooling of atoms, control of quantum states of
atoms and molecules, atomic interferometry, optical
pumping of powerful solid-state lasers.
It is known that, in the general case, the spectrum of
radiation of a semiconductor laser is determined by the
spectral dependence of the amplification of the active
medium and frequency selectivity of a laser cavity,
formed by the faces of a laser crystal or an external
cavity. The gain spectrum of laser is determined by
elemental composition of laser and the peculiarities of
the junction structure of the semiconductor laser. The
peak position of laser gain depends on the temperature of
the crystal and the excitation current, and can be shifted
in more or less wide limits by their regulation. To obtain
the radiation with a narrow spectrum, the most common
method is to create a selective feedback in a laser using
an external cavity containing dispersion elements, in
particular, diffraction gratings [1].
An important parameter of the frequency selection
scheme that ultimately determines the characteristics of
the laser is the optical feedback level that should be
sufficient to suppress undesirable frequencies and at the
same time would not excessive in terms of the effect on
the energy parameters of the laser. In this relation, we
would like to draw attention to the possibility of creating
an adjustable feedback in the external cavity with volume
holographic grating (VGH). In recent years, the external
cavity with VGH have attracted considerable attention
both for creation of high-monochromatic lasers with high
stability of the radiation wavelength [2-4], and,
importantly, for work in external cavities of laser-array
bars with high output power of radiation [5, 6].
In this paper, the general principles of the
semiconductor lasers radiation spectrum control are
illustrated using the examples of schemes with an
external resonator including VHG, which makes it
possible to achieve an increased efficiency and output
power in comparison with traditional cavities with
reflective gratings. The precise feedback control in this
design of external cavities is achieved by fine tuning the
VHG position. The results of an experimental study of
the dependence of the spectrum and the output power of
a laser-array bar on temperature are also given in order to
study the additional control parameters of laser diodes
and diode arrays with external cavities.
2. Temperature dependence of the laser diode bar
radiation spectra
To develop the laser systems with controlled output
spectrum, the temperature dependence of the laser
radiation wavelength should be taken into account. It is
known that the amplification line of a semiconductor
laser shifts to higher energies with increasing the
injecting current, and the temperature shift is opposite.
For example, for the InGaAlP laser diode the gain curve
SPQEO, 2018. V. 21, N 4. P. 424-428.
Bashchenko S.M., Marchenko L.S., Negriyko A.M. et al. Spectral control of powerful diode lasers with enhanced …
425
Fig. 1. The laser diode bar with the temperature control units:
laser output (1), laser diode (2), temperature sensor (3), brass
plate (4), Peltier elements (5), and aluminum heat sinks with
cooling water (6).
undergoes a temperature shift with a coefficient of about
0.23 nm/K. The cavity modes shift due to the laser
crystal thermal expansion and due to the refractive index
changes with the temperature and current. For the single
longitudinal mode, the coefficients of temperature and
current dependence on average are +0.06 nm/K
(–45 GHz/K) and + 0.003 nm/mA (–2.4 GHz/K) [7]. The
difference in the temperature dependence of the gain
curve and the resonance modes leads to jumping modes
at the temperature changes and, hence, to limiting the
achievable region of continuous frequency tuning. In
addition to external factors, the aging of the laser diode
has significant influence on the wavelength of output
radiation.
We performed more detailed investigations of the
temperature shift of the line of generation of the diode-
array bar to ascertain the influence of temperature on the
output parameters of the laser and the required level of
temperature stability in wavelength-sensitive applications
of this type lasers, in particular, in spectroscopy and
optical pumping of solid-state lasers.
The laser diode bar (20 W, 25 A, “Silver Bullet”
type, Northrop Grumman) output power and spectrum
within the temperature range 10…46 °C was studied. The
bar of six laser diodes were soldered to thin (2 mm) brass
silver plated plates with three Peltier elements fastened
through the thermal paste to the opposite sides of the
brass plates (Fig. 1). Opposite side of Peltier elements
was fixed to common water cooled aluminum heat sink
radiator. The rectangular 500 µs current pulses with the
amplitude close to 13 A were used for laser diodes
operation. The radiation spectrum was recorded by the
Ocean Optics USB 2000 spectrometer. The temperature
of laser diodes was measured by the miniature
temperature sensor Honeywell 777.
Fig. 2. Dependence of the laser diode radiation spectrum on
temperature.
Fig. 3. Diode laser output (a.u.) vs temperature (°C).
Laser emission spectral lines shapes of single laser
diode from the diode bar on the temperature within the
range 10 to 46 °C is shown in Fig. 2. The power dropping
with temperature is shown in Fig. 3 and gain peak shift –
in Fig. 4.
The gain peaks spectral positions of separate laser
diodes from single bar was varied in the spectral range
not wider than 1 nm, and the temperature dependence of
intensity and spectrum for all six investigated diodes
were similar. The gain peak temperature shift is
0.34 nm/K in the studied temperature range. The shapes
of emission spectral lines for all temperatures in the
studied range are practically identical with spectrometer
resolution limited FWHM near 3-4 nm. The temperature
shifts of gain peaks and lowering the laser output are
typical for semiconductor laser diodes, and the results are
in good agreement with the known theoretical models
[8].
1
2
3
5
6
4
SPQEO, 2018. V. 21, N 4. P. 424-428.
Bashchenko S.M., Marchenko L.S., Negriyko A.M. et al. Spectral control of powerful diode lasers with enhanced …
426
Fig. 4. Gain peaks positions (nm) vs temperature (°C).
3. VHG for tunable external-cavity diode lasers
Most of tunable external-cavity diode lasers are based on
one of two main configurations: Littrow or Littman–
Metcalf setup [1]. The output beam of the laser diode is
collimated using a lens and directed on a diffraction
grating. The optical feedback level in external cavity
diode lasers is defined by the portion of laser output
directed into the laser active volume by external cavity
elements (grating or grating + mirror). The regulation of
optical feedback level within wide limits is rather
complicated: the diffraction efficiency of metallic blazed
or surface holographic grating is fixed and the mirror
misalignment is only applied for regulation of the
reflected beam intensity.
We analyzed the optical feedback control in
Littman–Metcalf configuration of external cavity diode
laser with VHG (Fig. 5).
The diffraction efficiency of volume holographic
grating is angle- and wavelength-dependent and reaches
its maximum under the Bragg conditions.
The optimal optical feedback is rather important for
stable laser operation and for maximizing the laser
output. For a laser diode, the low quality of its resonator
formed by parallel faces of a laser crystal makes the
mode of generation extremely sensitive to optical
feedback. This sensitivity is further enhanced by the
weak spectral dependence of the amplification curve of
the active medium. The real influence of the feedback on
the radiation parameters (spectrum, modular
composition, output power) depends on the phase,
amplitude and polarization of the light coming back into
the laser [9, 10]. For different levels of optical feedback,
modes with expanding or narrowing the line of radiation,
mode jumps, coherence collapse with chaotic regime of
non-damped relaxation oscillations and, finally, stable
single-mode generation in the mode of strong optical
feedback with substantially reduced line width and stable
laser operation take place. In the case of sufficient
Fig. 5. Schematic of the external cavity diode laser based on the
transmitting volume holographic grating.
frequency selectivity of the resonator, the laser operates
in a single longitudinal mode with a narrow line for all
phases of radiation that are returned to the laser cavity.
VHG is the diffractive optical element, which
operation is described by the Kogelnik theory [11]. The
angular selectivity of the transmission VHG with a
sinusoidal profile of the refractive index spatial
modulation is determined by the Kogelnik formula:
( )
2
2
21222
1
sin
ν
ξ
+
ν+ξ
=η
where
( )θ∆+θλ
π
=ν
0
1
cos
Tn
is the phase incursion, the
parameter that defines the maximum diffraction
efficiency of VHG, when the Bragg condition is satisfied
(n1 – modulation of refraction index of photopolymer with
a thickness T; θ0 – Bragg angle in medium; ∆θ – detuning
from Bragg angle in the medium; λ – laser emission
wavelength);
( ) ( )θ∆+θΛ
λ∆π
−
θ∆+θλ
θθ∆π
=ξ
0
2
0
0
cos2cos
cos
n
TT
are angular and wavelength deviations from the Bragg
condition (Λ is the spatial period of modulation of
refractive index of photopolymer grating; ∆λ – deviation
from the central wavelength of laser emission; n –
average refraction index of grating media
(photopolymer)). If
2
π
=ν and ∆θ = 0, then the
efficiency of transmitting grating is 100%.
Rotating VHG makes it possible to adjust the
energy distribution of the laser radiation between the
external resonator and the output beam (Fig. 6).
SPQEO, 2018. V. 21, N 4. P. 424-428.
Bashchenko S.M., Marchenko L.S., Negriyko A.M. et al. Spectral control of powerful diode lasers with enhanced …
427
Fig. 6. Angular dependence of the partial beams intensity in the
extended cavity.
Fig. 7. Optical intensity redistribution at the VHG presence in
the laser cavity.
In the external cavity design shown Fig. 5, rotation
of the mirror allows tuning the coarse wavelength, and
the mirror shift along the beam provides the fine laser
wavelength tuning within the free spectral range of the
external cavity. Accordingly, it is possible to consider a
scheme in which the optical feedback can be set at an
optimum level by appropriately setting the VHG in the
external cavity. The proper VHG design provides the
additional degree of freedom in optimization of laser
parameters.
5. Tuning the diode laser with VHG external cavity
In our experiments, we have used the volume
holographic grating recorded in the original
photopolymer composition developed in the Institute of
Physics PPC-488 [12]. The VHG active layer thickness is
33 µm, an average refractive index is 1.56 with amplitude
modulation of the refractive index 0.00667, and the
spatial modulation period of the refractive index of
0.92 µm [13]. Fig. 7 shows redistribution of the laser
output intensity between output laser (1) and diffracted
(2) beams.
The intensity of retro reflected by external cavity
mirror beam as parameter of the feedback efficiency is
shown, too (3). The operation point of optimal optical
Fig. 8. Frequency tuning of ECDL based on VHG.
feedback with the stable operation of ECDL is marked at
the detuning angle near 1.25° and corresponds to the
optical feedback efficiency near 10%.
In our experiment, we have used the diode laser
HLDP-650-A-5-02 with non-AR front facet. In this
regard, to increase the range of mode-hop free frequency
tuning range of the laser it was necessary to change the
length of the external resonator and the position of
longitudinal modes of a laser diode crystal
simultaneously. This was achieved by applying a voltage
to the piezoelectric transducer of cavity mirror. The
applied voltage was proportional to the laser diode
injection current. ECDL emission was analyzed with a
Fabry–Perot etalon within the free spectral range
1.33 GHz. The results are depicted in Fig. 8. It is seen
that mode-hop free tuning range of ECDL with VHG
reaches 8 GHz.
6. Conclusions
The diode lasers with external cavities are widely used in
laser cooling, spectroscopy, metrology, atomic
gravimetry, interferometry, environmental control,
atomic clocks, quantum key cryptography, etc. The laser
sources having both narrow radiation spectra and high
laser output power are very attractive for many
applications. The frequency-selective optical feedback in
the diode laser external cavity containing VHG can be
finely tuned to the optimal grade with the ability to
enhance the laser output. The VHG containing cavities
are rather promising for application in the design of
power diode lasers with narrow spectral line of output
radiation. The mode-hope free tuning of ECDL with
VHG has been demonstrated and the temperature
dependence of gain peak spectral position of power diode
laser bar has been measured.
Acknowledgment
The work was supported by NAS Ukraine projects 1.4.
B/185, 1.4. ВЦ/188 and 1.4. ВЦ/201.
References
1. Cunyun Ye. Tunable External Cavity Diode Lasers.
World Scientific, 2004.
SPQEO, 2018. V. 21, N 4. P. 424-428.
Bashchenko S.M., Marchenko L.S., Negriyko A.M. et al. Spectral control of powerful diode lasers with enhanced …
428
2. Hieta T., Vainio M., Moser C., Ikonen E. External-
cavity lasers based on a volume holographic grating
at normal incidence for spectroscopy in the visible
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3. Ho-Chiao Chuang, Chang-Ray Chang, Chun-Chia
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laser using a volume holographic grating. Optics &
Laser Technology. 2012. 44, No 7. P. 2182–2185.
4. Matsnev I.V. and Negriyko A.M. Controlled optical
feedback in external cavity diode laser with volume
holographic grating. 2016 IEEE 7-th Intern. Conf.
on Advanced Optoelectronics and Lasers (CAOL),
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5. Volodin B.L., Dolgy S.V., Melnik E.D., Downs E.,
Shaw J., Ban V.S. Wavelength stabilization and
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diodes and arrays by use of volume Bragg gratings.
Opt. Lett. 2004. 29, No 16. P. 1891–1893.
6. Chann B., Nelson I., Walker T.G. Frequency-
narrowed external-cavity diode-laser-array bar. Opt.
Lett. 2000. 25, No 18. P. 1352–1354.
7. Favre F., Le Guen D. Emіssіon frequency stabіlіty
іn sіngle-mode-fіbre optіcal feedback controlled
semіconductor lasers. Electron. Lett. 1983. 19, No
17. P. 663–665.
8. Menzel U. et al. Modelling the temperature
dependence of threshold current, external
differential efficiency and lasing wavelength in QW
laser diodes. Semicond. Sci. Technol. 1995. 10, No
10. P. 1382.
9. Tkach R.W. and Chraplyvy A.R. Regimes of
feedback effects in 1.58 µm distributed feedback
lasers. J. Lightwave Technol. 1986. 4, No 11. P.
1655–1661.
10. Schunk N. and Petermann K. Numerical analysis of
the feedback regimes for a single mode
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12. Smirnova T., Sakhno O. PPC: Self-developing
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SPIE. 2000. 4149. P. 106–112.
13. Sakhno O.V., Goldenberg L.M., Stumpe J. and
Smirnova T.N. Effective volume holographic
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Authors and CV
Sergii M. Baschenko, PhD in
Physics and Mathematics Sciences,
Senior researcher of the Institute of
Physics of NASU, vice-head of Laser
Spectroscopy dep., Authored 20
scientific publications. The area of
scientific interests – laser, laser
spectroscopy, laser for environmental
application.
Ludmila S. Marchenko, junior
researcher of the Institute of Physics
of NASU, Laser Spectroscopy dep.,
Authored 4 scientific publications.
The area of scientific interests – laser,
laser spectroscopy, laser for
environmental application.
Dr.Sci, Corresponding member of
NAS of Ukraine Anatoliy Negriyko,
head of Laser spectroscopy
department of the Institute of Physics
NAS of Ukraine, Kiev. Current
Research Activities – laser physics,
high resolution laser spectroscopy,
interaction of laser radiation with
matter, mechanical action of light on
the free atoms, molecules and micro- and sub-micro-
sized solid particles, laser applications. More than 140
scientific papers, books "Dynamics of atoms and
molecules in coherent laser fields" (co-author), Naukova
dumka edition, Kyiv, 2008, 239 p., "Optical frequency
standards" parts І-ІІІ, (co-author), Colegium edition,
Kharkiv, 2009-2017. For the first time, he has
experimentally observed and studied the forces of
stimulated light pressure on atoms and molecules. With
his participation, the frequency stabilized He-Ne lasers
with relative frequency stability 5 · 10
−13
for averaging
time 100 s, iodine absorption cells for metrology
application, laser sources with narrow radiation lines for
laser spectroscopy on the base of CW dye lasers,
semiconductor and gas lasers were designed and studied.
Prof. Tatiana N. Smirnova, Principal
Researcher of the Institute of Physics
NAS of Ukraine, Kiev. She is an
author of more than 150 scientific
publications, 1 monograph and 10
certificates of authorship and patents.
Current Research Activities –
photopolymer and organic-inorganic nanocomposite
materials for holographic structuring; mechanisms,
thermodynamics and theory of periodic structures
formation; elaboration of a common concept of the
nanocomposite components selection for improvement of
holographic properties of materials; development of a
series of improved high efficient nanocomposites
including nanoparticles of different nature; optical,
nonlinear optical, and laser properties of nanocomposites
and ordered structures on their basis.
Igor V. Matsnev. Junior researcher
of the Institute of Physics of National
Academy of Science, Kyiv, Ukraine.
Authored 12 scientific publications.
The area of scientific interests is
nonlinear laser spectroscopy of atoms
and molecules, laser physics.
|
| id | nasplib_isofts_kiev_ua-123456789-215315 |
| institution | Digital Library of Periodicals of National Academy of Sciences of Ukraine |
| issn | 1560-8034 |
| language | English |
| last_indexed | 2026-03-23T19:00:14Z |
| publishDate | 2018 |
| publisher | Інститут фізики напівпровідників імені В.Є. Лашкарьова НАН України |
| record_format | dspace |
| spelling | Bashchenko, S.M. Marchenko, L.S. Negriyko, A.M. Smirnova, T.N. Matsnev, I.V. 2026-03-12T08:53:08Z 2018 Spectral control of power diode lasers with enhanced output by an external cavity based on a volume holographic grating / S.M. Bashchenko, L.S. Marchenko, A.M. Negriyko, T.N. Smirnova, I.V. Matsnev // Semiconductor Physics Quantum Electronics & Optoelectronics. — 2018. — Т. 21, № 4. — С. 424-428. — Бібліогр.: 13 назв. — англ. 1560-8034 PACS: 42.40.Eq, 42.55.Px, 42.60.Da https://nasplib.isofts.kiev.ua/handle/123456789/215315 https://doi.org/10.15407/spqeo21.04.424 To achieve the maximum efficiency in the single-frequency lasing mode of a laser diode with an external cavity, it is necessary to minimize losses in the optical system for the output beam and to provide the optimal frequency-selective feedback. In this paper, we have investigated the scheme of an external cavity diode laser (ECDL) based on a phase volume holographic grating (VHG). Angular and spectral selectivities of the holographic grating allow for adjusting the optical feedback with low losses in the cavity, and it can be used for the frequency narrowing of diode-array bars. Here, the optimal parameters of VHG and the temperature dependence of the diode laser bar spectrum have been studied, and the proposals on VHG design have been developed. The work was supported by NAS Ukraine projects 1.4.B/185, 1.4. ВЦ/188 and 1.4. ВЦ/201. en Інститут фізики напівпровідників імені В.Є. Лашкарьова НАН України Semiconductor Physics Quantum Electronics & Optoelectronics Optoelectronics and optoelectronic devices Spectral control of power diode lasers with enhanced output by an external cavity based on a volume holographic grating Article published earlier |
| spellingShingle | Spectral control of power diode lasers with enhanced output by an external cavity based on a volume holographic grating Bashchenko, S.M. Marchenko, L.S. Negriyko, A.M. Smirnova, T.N. Matsnev, I.V. Optoelectronics and optoelectronic devices |
| title | Spectral control of power diode lasers with enhanced output by an external cavity based on a volume holographic grating |
| title_full | Spectral control of power diode lasers with enhanced output by an external cavity based on a volume holographic grating |
| title_fullStr | Spectral control of power diode lasers with enhanced output by an external cavity based on a volume holographic grating |
| title_full_unstemmed | Spectral control of power diode lasers with enhanced output by an external cavity based on a volume holographic grating |
| title_short | Spectral control of power diode lasers with enhanced output by an external cavity based on a volume holographic grating |
| title_sort | spectral control of power diode lasers with enhanced output by an external cavity based on a volume holographic grating |
| topic | Optoelectronics and optoelectronic devices |
| topic_facet | Optoelectronics and optoelectronic devices |
| url | https://nasplib.isofts.kiev.ua/handle/123456789/215315 |
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