JP2002314176A - EXCITING METHOD OF OPTICAL AMPLIFIER OR LASER OSCILLATOR WITH 1.4 TO 1.52 mum BAND - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the exciting method of an optical amplifier or a laser oscillator with 1.4 to 1.52 μm band. SOLUTION: The optical amplifier with 1.4 to 1.52 μm band which is provided with an exciting light source, multiplexer/demultiplexer and an amplification optical waveguide is excited by the two or above types of different wavelengths of at least one wavelength from a range in the wavelengths 0.65 to 0.75 μm and one wavelength from a range in the wavelengths 1.35 to 1.45 μm.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to the field of 1.4 to 1.52.
The present invention relates to a method for exciting an optical amplifier or a laser oscillator used in optical communication in the μm band.

[0002]

2. Description of the Related Art In optical communication, a 1.55 .mu.m band, which is the lowest loss wavelength of a quartz fiber, and 1.3, which is a zero dispersion wavelength.
The μm band has been used. Research and development of optical amplifiers have been actively conducted for these wavelength bands, and particularly, the 1.55 μm band has been very successful. In recent years, high-speed and large-capacity Internet and data transmission have been demanded, and wavelength multiplexing communication (WDM) has been put into practical use from the viewpoint of increasing communication capacity. However, with the 1.55 μm band alone, there is a possibility that the capacity will eventually become insufficient, and there has been a movement to seek another band. In particular, there is a strong demand to use the entire wide transmission wavelength range of the quartz fiber from 1.3 to 1.7 μm for communication. For this reason, research on 1.47 μm band and 1.65 μm band fiber amplifiers to which Tm is added has been actively conducted.

[0003]

It has been proposed to use a low phonon glass fiber doped with Tm for amplification or laser oscillation in the 1.47 μm band (Journal of the 14th European Optical Committee, 1988). DNPayne and other Rareearth
-doping fiber laser and amplifiers pp49-53. and
IEEE.J.Quantum Electronics vol.24 (6) (1988) 920-
923). FIG. 1 shows the level of Tm. The amplification in the 1.47 μm band is performed by using the stimulated emission process of ³ H ₄ → ³ F ₄ , and actually has a wide gain and amplification band of 1.4 to 1.52 μm. As an excitation method, 1.0
A two-step excitation at 6 μm (JP-A-5-275792);
A method of directly exciting Tm ³ H ₄ in the band of 7 to 0.89 μm (Japanese Patent Application Laid-Open No. 4-265251), a method of two-step excitation in the 1.2 μm band (Japanese Patent Application Laid-Open No. 4-180279), and the like are disclosed. But,
It is known that the fluorescence lifetime of the ³ H ₄ level of Tm is shorter than the fluorescence lifetime of ³ F ₄ , and it is difficult to obtain the population inversion necessary for amplification or laser oscillation. Such a characteristic is called a self terminating mechanism, and is not suitable for highly efficient amplification or laser oscillation. Therefore, in order to short-life of the _{^{3 F 4, Eu, Tb,}} Ho, P
r (see JP-A-4-265251, JP-A-5-151451)
68, JP-A-7-45899). However, when these co-addition elements are added at a certain concentration or more, an undesired energy transfer occurs due to the absorption tail also in the 1.4 to 1.52 μm band of the target wavelength, for example.
Since it adversely affects amplification efficiency in the 1.52 μm band,
There are restrictions on the composition of the amplification medium. Although proposals have been made to excite the Tm-doped fiber at two wavelengths, many are short-wavelength light sources utilizing an up-conversion process (for example, JP-A-5-319858 and JP-A-8-307000).

On the other hand, recently, researches aimed at improving the excitation efficiency and the power conversion efficiency have been actively conducted. JP-A-2001-007426 and JP-A-2001-024263 show that two-wavelength excitation can amplify with higher efficiency than conventional one- or two-wavelength excitation. Also, S.Aozasa et al., OF
C2001 Technical digest series, PD1, F.Ray, etc., OFC20
The 01 Technical digest series, PD2, reports that a power conversion efficiency of over 40% can be obtained by one-wavelength excitation at 1.40 μm or two-wavelength excitation at 1.24 μm and 1.40 μm.

However, according to the method of S. Aozasa et al., Which excites at a wavelength of 1.40 μm, it cannot be efficiently excited to the upper level from ³ H ₆ in the ground state because there is no corresponding absorption (see FIG. 1). ). Further, in the F.Ray's method will be excited by the complex process of a light emitting lower level _{^{3 H 6 → 3 H 5 →}} 3 F 4 → 3 H 4, also the emission lower level ³ F _From passing through ₄ ,
This is not the most suitable excitation method for forming the population inversion. On the other hand, the method of Japanese Patent Application Laid-Open No. 2001-007426 uses a direct excitation from the base, so that it is a better excitation method than the above two methods, but ³ H ₄ → by a strong excitation light in the 0.8 μm band. ³ H
_Since stimulated emission of ₆ occurs, it cannot be said that it is necessarily suitable for highly efficient excitation. In the method of JP-A-2001-024263,
Although it overcomes the drawback of stimulated emission by excitation light, there is room for improvement in quantum efficiency.

[0006]

The present inventors have comprehensively considered the above problems, and as a result of intensive studies, have found that ³ H ₄ and ³ F ₄
Not only can efficiently form a population inversion between ³ H ₄ →
^The present inventors have found an excitation method capable of suppressing the emission of ³ H ₆ and amplifying with high efficiency, and have reached the present invention.

That is, the present invention provides a 1.4 to 1.52 μm band optical amplifier or laser oscillation device using an optical waveguide containing Tm in a core as an amplification medium, and at least a 0.65 to 0.75 μm excitation light source. A high efficiency 1.4 to 1.52 μm band optical amplifier or laser oscillator by pumping at two or more different wavelengths of at least one wavelength from the range and at least one wavelength from the range of 1.35 to 1.45 μm. Is provided.

Hereinafter, the present invention will be described in detail.

A highly efficient 1.4 to 1.52 to which Tm is added
μm band (energy difference: about 6800cm ^-1) to the optical amplification or laser oscillation, the phonon energy 700 cm ^-1
The following low phonon energy materials are suitable, and high phonon energy materials (generally about 1000 cm ^-1 ) such as silica-based oxides and boric acid-based oxides are considered unsuitable. Such low phonon energy glass materials include halide glass, chalcogenide glass, halide oxide glass, chalcogenide glass, tellurite glass (tellurite glass), bismuthate glass,
Germanate glass, gallate glass and the like are known. However, these low phonon energy glass materials are also well known as up-conversion laser materials, and the excitation energy is consumed to emit red or blue light by a normal excitation method, and light emission in the 1.4 to 1.52 μm band is emitted. The efficiency is known to be very low. Also ³
The fluorescence lifetime of H ₄ is shorter than the fluorescence lifetime of ³ F ₄ , which is the lower level of light emission, and is considered to be a typical example of a self-stopping mechanism. Is extremely low (eg JYAllain et al., Electron
ics lett. 25 (1989) 1660-1662). For this reason, various methods described above have been tried, but none of these methods is optimal.

In contrast to these methods, the present invention has a wavelength of 0.6.
By exciting at two or more different wavelengths, at least one wavelength from a range of 5 to 0.75 μm and at least one wavelength from a range of 1.35 to 1.45 μm,
It has been found that the formation of the population inversion is facilitated, the emission of ³ H ₄ → ³ H ₆ is hard to occur, and the amplification or laser oscillation can be performed with high efficiency with low excitation power.

The excitation method of the present invention will be described in more detail.
(FIG. 2). First, Tm contained in the core of the optical waveguide
Ions are selected from small wavelengths of 0.65 to 0.75 μm.
At least one wavelength of excitation light (hereinafter referred to as excitation light 1).
The ground state (^ThreeH₆) →^ThreeF_TwoOr^ThreeF_ThreeTo excite
(Excitation process 1). Next, radiationless relaxation process (radiation process 1)
Through^ThreeH_FourRelaxed^ThreeH_Four→^ThreeF_FourTransition (radiation process
2) emission or amplification in the 1.4 to 1.52 μm band
You. Next, the wavelength is selected from the range of 1.35 to 1.45 μm.
Pump light of at least one wavelength (hereinafter referred to as pump light 2).
The lower emission level (^ThreeF_Four) →^ThreeH_FourSub-level of
(Excitation process 2). With this excitation^ThreeF_FourExistence
Effective probability can be reduced and self-stop mechanism can be avoided
In addition, the highest quantum efficiency can be obtained. Finally, again
^ThreeH_Four→^ThreeF_Four1.4 to 1.52 μm according to (radiation process 2)
The band emits light. In this excitation method, the excitation light 2
According^ThreeH _Five→^ThreeF_Two(Excitation process 3)^ThreeH_Fiveof
There is a feature that the existence probability can be efficiently reduced.

When the existence probability of ³ H ₅ increases, the absorption spectrum of Tm and the ESA spectrum (FIG. 3) show 1.4.
Excited state absorption (ESA :) in a very wide wavelength range of ~ 1.7 μm
Excited state absorption) occurs, and the amplification efficiency is significantly reduced. Although the present invention can efficiently avoid this ESA, pump light in the 1.5 to 1.7 μm band may be added. The method for reducing ESA loss around 1.5μm to _{^{(3 H 5 → 3 F 3}} ), also has the effect of improving the gain characteristics in a long wavelength side (T.Kasamatsu other, P
roceedings OAA'99, PDP1), gain-shifted Tm-doped fiber amplifier (GS-TDFA: Gain Shifted Thulium Dop)
ed Fiber Amplifier).

In the excitation method of the present invention, as can be seen from FIG. 2, a quasi-three-level process using ³ F ₄ as a virtual ground level is provided, and it is extremely easy to form a population inversion. Moreover, since ^{the 3} H ₄ → ³ strong light 0.8μm band corresponding to the energy difference between the H ₆ does not exist in this method, unlikely to occur stimulated emission of _{^{3 H 4 → 3 H 6,}} 3 H 4 → 3 F ₄ can increase the transition probability. Also, among the excitation wavelengths 1, 0.67
The band of about 0.72 μm is particularly preferable because the up-conversion process of ³ H ₄ → ¹ D ₂ and ³ H ₅ → ¹ G ₄ can be avoided at the same time. Further, among the excitation wavelengths 2, 1.35 to 1.42
The μm band is particularly preferable because it hardly causes noise in the amplification process of ³ H ₄ → ³ F ₄ .

The optimum wavelength selection of the excitation wavelength 1 and the excitation wavelength 2 cannot be specified unconditionally because it varies depending on the added concentration of Tm and the type of the glass material, but is set within the range of each wavelength band of the present invention. be able to. For example, Tm: ZBLA
For N (fluoride glass), 0.68 μm (excitation wavelength 1) and 1.40 μm for which a high power semiconductor laser is available
(Excitation wavelength 2) can be selected. The optimal combination of the pumping light powers cannot be specified unconditionally because they depend on the Tm concentration, the material of the optical waveguide, the numerical aperture of the waveguide, etc., but ([Pumping power 1 power] / [Pumping wavelength 1 power] + The power of the pumping wavelength 2]) It is preferable that the pumping power ratio (R) expressed by 100% is in the range of 0% <R ≦ 82.5%. Excitation wavelength 2 (wavelength 1.3)
(5 to 1.45 μm) is weak, it is difficult to form a population inversion between ³ H ₄ and ³ F ₄ , and a sufficient amplification efficiency cannot be obtained. Further, the pump power ratio (R) is 1.5% ≦ R ≦ 78.
%, The excitation wavelength 2 is 2
This is particularly preferable because a gain improvement of dB or more can be achieved.

When the excitation method of the present invention is used, it is apparent that any material capable of amplifying the 1.47 μm band in the Tm-added medium can be used. As such a material, glass having a low phonon energy is generally used, and in particular, chalcogenide glass, halide glass, chalcogenide glass, halide oxide glass,
Tellurite glass (tellurite glass), bismuthate glass, germanate glass, and gallate glass are preferred.

As the excitation laser, a semiconductor laser,
Any laser that oscillates in the excitation wavelength band of the present invention, such as a dye laser, a solid laser, and a gas laser, may be used.
Particularly preferred are a semiconductor laser with a fiber pigtail, a solid laser coupled with a fiber, and a fiber laser. In terms of price and size, a semiconductor laser is suitable as an excitation light source. In addition, in order to enhance the pumping efficiency by making full use of the Tm absorption band, a laser having a wide oscillation wavelength band (for example, a Raman laser) is used, or a plurality of lasers having different wavelengths in each excitation wavelength band are combined. Is also effective.

When configuring an optical amplifier, an optical communication optical element such as a wavelength division multiplexing element (WDM) or an optical isolator can be used as needed. In addition, it is preferable that a gain monitoring function and a gain equalization function are built in or attached to the amplifier because the reliability of the optical communication system is improved.
For monitoring the gain, any method may be used as long as the method can substantially compare the incident signal light intensity and the output signal light intensity. In the case of performing wavelength division multiplexing communication, a method capable of detecting and monitoring each signal assigned to each wavelength is desirable. The gain equalization function may be a passive method or an active method. As a passive gain equalization method, a configuration using an optical filter is simple. The active gain equalization method comprises a gain monitoring function and a feedback function, substantially compares the incident signal light intensity and the output signal light intensity, and may use any method as long as the method can keep the gain constant. . In recent years, a method of changing the power of each stage and the intensity of the excitation light in each stage and changing the power ratio for each excitation wavelength has been widely used. When performing wavelength division multiplexing communication, it is desirable to use a method that can equalize the gain for each signal assigned to each wavelength. Although the function is the same as the gain equalization function, the output equalization function for keeping the output signal light intensity constant is also effective like the gain equalization function. Preferably, these functions are automatically adjustable by a remotely programmable microprocessor or the like.

When a laser oscillator is configured, a high output can be achieved by connecting the optical waveguides in a ring shape or by connecting a plurality of optical waveguides in series or in parallel. Also, narrow band oscillation and wavelength tunable oscillation using a fiber grating or the like, and ultrashort pulse oscillation by pulse compression are possible.

As described above, the excitation wavelength is set to 0.65 to 0.65.
By providing two-wavelength pumping with a 0.75 μm band and a wavelength of 1.35 to 1.45 μm, a 1.4 to 1.52 μm band optical amplifier or laser oscillator with higher efficiency than ordinary one- or two-wavelength pumping is provided. it can.

Hereinafter, the present invention will be further described with reference to examples, but the present invention is not limited to these examples.

[0021]

Example 1 Fluoride glass fiber containing 0.2 mol% of Tm added to a core was used. The basic glass compositions of the core and the clad are shown below. Tm replaces La. The number is m
ol%. Core: 51ZrF ₄ -19BaF ₂ -4.5LaF ₃ -2YF ₃ -2AlF ₃ -13.5LiF-8Pb
F ₂ clad: 40HfF ₄ -10ZrF ₄ -19BaF ₂ -3LaF ₃ -2YF ₃ -4AlF ₃ -22
NaF This fiber had a relative refractive index difference of 1.1%, a cutoff wavelength of 0.65 μm, and a core diameter of 2.2 μm. The fiber length is 14m.

Next, the configuration of the optical amplifier used for the measurement is shown in FIG.
Shown in For excitation, a semiconductor laser 2 with a wavelength of 0.69 μm
And a semiconductor laser 3 having a wavelength of 1.40 μm, and are coupled to the optical amplification fluoride fiber 1 via the optical multiplexing / demultiplexing element 4 and the high NA quartz fiber 5. The quartz fiber 5 and the fluoride fiber 1 were bonded using a V-groove block, and the bonded end face was obliquely optically polished to reduce reflection loss, and fixed with an ultraviolet-curable optical adhesive. 1.
The signal light from the signal generator 6 in the 47 μm band enters the amplifying fiber via the optical multiplexing / demultiplexing element 4, the amplified outgoing light passes through the optical isolator 7, and the small signal gain is measured in the measuring instrument 8. Was. The input signal light has a wavelength of 1.47μ.
m, continuous light having a power of -30 dBm. Wavelength 1.4
FIG. 5 shows the small signal gain when pumping at a single wavelength of 0 μm and the small signal gain when pumping at two wavelengths simultaneously. The input power in the case of two-wavelength pumping is the total power of two wavelengths, and the pumping power ratio (R) is fixed at 40%. It can be seen that in the two-wavelength pump, the gain is improved by 5 dB or more with respect to the single-wavelength pump, and the threshold value is low.

Example 2 An experiment was performed using the same fluoride fiber as in Example 1 and changing the excitation power ratio (R) with the same configuration. The incident condition and the excitation wavelength of the signal light are the same as those in the first embodiment,
The total power of the two wavelengths was fixed at 100 mW and measured.
FIG. 6 shows the results. When the excitation power ratio (R) at an excitation wavelength of 0.69 μm is in the range of 0 <R ≦ 82.5%, the wavelength is 1.4.
It can be seen that the gain is higher than in the case of 0 μm single wavelength pumping. In particular, when the power ratio is in a range of 1.5 ≦ R ≦ 78%, the gain is 2 dB higher than the gain in the case of the 1.4 μm single wavelength pump.
As described above, the gain was high.

Example 3 A small signal gain was measured in the same configuration as in Example 1, except that the amplification medium was an In-based fluoride glass fiber. The addition concentration of Tm is 0.2 mol%, and a part of Gd is substituted. The numbers are mol%. Core composition: 18InF ₃ -12GaF ₃ -20ZnF ₂ -27BaF ₂ -3PbF ₂ -10GdF ₃
-10YF ₃ cladding composition: 18InF ₃ -12GaF ₃ -20ZnF ₂ -18BaF ₂ -12SrF ₂ -1
0GdF ₃ -10YF ₃ The relative refractive index difference of this fiber was 1.1%, and the cutoff wavelength was 0.65 μm. The fiber length used for the measurement is 14 m. For the excitation, a semiconductor laser having a wavelength of 0.695 μm and a semiconductor laser having a wavelength of 1.38 μm were used. As in Example 1, the gain was measured for the case of single-wavelength pumping of 1.38 μm and the case of dual-wavelength pumping (pumping power ratio (R) = 40%). As a result, as shown in FIG. The higher gain was 5 dB or more.

Example 4 A small signal gain was measured with the same configuration as in Example 1 and a tellurite-based oxide glass fiber as the amplification medium. Tm
Is 0.6 mol%, and a part of La is substituted. The numbers are mol%. Core composition: 90TeO ₂ -8BaO-2La ₂ O ₃ Cladding composition: 81TeO ₂ -16BaO-3Y ₂ O ₃ The relative refractive index difference of the fiber was 0.7%, and the cutoff wavelength was 0.65 μm. The fiber length used for the measurement is 2 m. For the excitation, a semiconductor laser having a wavelength of 0.695 μm and a semiconductor laser having a wavelength of 1.40 μm were used.
The pump power ratio (R) is 40%. As shown in FIG. 8, the gain was higher by 3 dB or more in the two-wavelength excitation than in the 1.40 μm single-wavelength excitation.

Example 5 A small signal gain was measured in the same configuration as in Example 1, except that the amplification medium was a bismuth-based oxide glass fiber. The addition concentration of Tm is 0.6 mol%, and a part of La is substituted.

Core glass composition: 75Bi ₂ O ₃ -18B ₂ O ₃ -5SiO ₂ -2La ₂ O ₃ Clad glass composition: 70Bi ₂ O ₃ -15CdO-15B ₂ O ₃ Fiber has a relative refractive index difference of 1.2%. And the cutoff wavelength was 0.65 μm. The fiber length used for the measurement is 2 m. For the excitation, a semiconductor laser having a wavelength of 0.68 μm and a semiconductor laser having a wavelength of 1.40 μm were used. As in Example 1, the gain was measured in the case of 1.40 μm single-wavelength excitation and in the case of dual-wavelength excitation (excitation power ratio (R) = 50%). As a result, as shown in FIG. The higher gain was 3 dB or more.

Example 6 A small signal gain was measured using the same configuration as in Example 1 except that the amplification medium was a gallate glass fiber. The addition concentration of Tm is 0.3 mol%. Core composition: 30K ₂ O-30Ta ₂ O ₃ -40Ga ₂ O ₃ Clad composition: 30K ₂ O-25Ta ₂ O ₃ -45Ga ₂ O ₃ The relative refractive index difference of this fiber is 1.2%, and the cutoff wavelength is 0. .65 μm. The fiber length used for the measurement is 6 m. For the excitation, a semiconductor laser having a wavelength of 0.695 μm and a semiconductor laser having a wavelength of 1.35 μm were used. As in the case of Example 1, the result of measurement of the case of single-wavelength excitation of 1.35 μm and the case of dual-wavelength excitation (excitation power ratio (R) = 50%) were measured. As shown in FIG. The gain was as high as 3 dB or more.

Example 7 A small signal gain was measured in the same configuration as in Example 1 except that the amplification medium was a sulfide glass fiber. The added concentration of Tm is 0.2 mol%. The numbers are mol%.

Core: 30In ₂ S ₃ -40Ga ₂ S ₃ -30La ₂ S ₃ Clad: 12Al (PO ₃ ) ₃ -11AlF ₃ -30.5RF ₂ -46.5MF ₂ (R: M
g, Ca M: Sr, Ba) Tm replaces La. The relative refractive index difference of this waveguide was 1.2%, and the cutoff wavelength was 0.65 μm. The fiber used for the measurement is 10 m in length. Excitation uses a semiconductor laser having oscillation wavelengths of 0.70 μm and 1.45 μm, and the excitation power ratio (R) is 20%. The signal light wavelength is 1.50 μm and the power is −30 dBm. As a result of measuring the gain in the case of single-wavelength pumping at 1.45 μm and the case of dual-wavelength pumping as in Example 1, as shown in FIG. 11, the two-wavelength pumping had a higher gain by 3 dB or more.

Embodiment 8 The same fiber and the same configuration as in Embodiment 1 were used,
The power conversion efficiency (PCE) was measured by changing the signal light power of 47 μm. The power conversion efficiency is defined by the following equation.

PCE (%) = [(output signal power) − (input signal power)] / (excitation power) × 100 The excitation power was fixed to 100 mW in total. In the case of two wavelengths, a semiconductor laser having a wavelength of 0.69 μm and a wavelength of 1.4
A semiconductor laser of 0 μm was used. The excitation power ratio (R) is fixed at 40%. FIG. 12 shows the power conversion efficiencies in the case where excitation is performed at a single wavelength of 1.40 μm and the case where excitation is performed simultaneously at two wavelengths. It can be seen that the power conversion efficiency can be greatly improved with dual-wavelength excitation over single-wavelength excitation.

[0033]

By using the excitation method of the present invention,
Highly efficient 1.4 to 1.52 μm band optical amplifier or 1.4
A laser oscillator of 1.52 μm band can be constructed.

[Brief description of the drawings]

FIG. 1 is a level diagram and an absorption spectrum of Tm.

FIG. 2 is a diagram illustrating the level of Tm and the excitation method of the present invention.

FIG. 3 is a diagram showing an absorption cross section from each level of Tm.

FIG. 4 is a configuration diagram of an amplifier according to the first embodiment.

FIG. 5 is a diagram showing pump power dependence of the amplification factor in the first embodiment.

FIG. 6 is a diagram showing the power ratio dependence of the amplification factor of the excitation wavelength 1 and the excitation wavelength 2 in Example 2.

FIG. 7 is a diagram illustrating the dependence of the amplification factor on the excitation power in the third embodiment.

FIG. 8 is a diagram illustrating pump power dependence of the amplification factor in the fourth embodiment.

FIG. 9 is a diagram showing pump power dependence of the amplification factor in Example 5.

FIG. 10 is a diagram showing pump power dependence of the amplification factor in Example 6.

FIG. 11 is a diagram showing pump power dependence of the amplification factor in Example 7.

FIG. 12 is a diagram illustrating the signal light power dependence of the power conversion efficiency according to the eighth embodiment.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 optical amplification fiber 2 light source for supplying excitation wavelength 1 3 light source for supplying excitation wavelength 2 4 optical multiplexing / demultiplexing element 5 high NA quartz fiber 6 signal light generator in wavelength 1.4 to 1.52 μm band 7 optical isolator 8 Measuring instrument

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Natsumura Natsumura 5253 Oki Ube, Oji, Ube City, Yamaguchi Prefecture Inside the Chemical Research Laboratory of Glass Co., Ltd. (72) Inventor Kiyotaka Miura 5253 Oki Ube Odai, Ube City, Yamaguchi Prefecture Central Inside the Chemical Research Laboratory of Glass Co., Ltd. 5F072 AB07 JJ02 PP07 RR01 YY17

Claims (5)

[Claims] 1. A 1.4 to 1.52 μm band optical amplifier including at least a pumping light source, a multiplexer / demultiplexer, and an amplification optical waveguide, wherein the core of the amplification optical waveguide contains Tm and has a wavelength of 0.65 μm. Pumping at two or more different wavelengths, at least one wavelength (excitation wavelength 1) from the range of 0.75 μm to at least one wavelength (excitation wavelength 2) of the range of 1.35 to 1.45 μm. Features 1.4
Excitation method of optical amplifier of 1.52 μm band. 2. A 1.4 to 1.52 μm band laser oscillator having at least a pumping light source, a multiplexer / demultiplexer, and an amplification optical waveguide, has at least one wavelength (pumping wavelength) in a wavelength range of 0.65 to 0.75 μm. 1) and wavelengths of 1.35-1.
At least one wavelength (excitation wavelength 2) from the range of 45 μm
Pumping at a wavelength of two or more different wavelengths from each other. 3. The core of the amplification optical waveguide is made of a halide oxide glass, halide glass, chalcogenide glass, chalcogenide glass, tellurite glass, bismuthate glass, germanate glass, gallate glass to which Tm is added. 3. The pumping method for a 1.4 to 1.52 [mu] m band optical amplifier or a 1.4 to 1.52 [mu] m band laser according to claim 1 or 2, comprising at least one kind of glass selected from the group consisting of: How to excite the oscillator. 4. The pumping method for a 1.4 to 1.52 μm band optical amplifier according to claim 1, wherein at least one of the pumping light sources is a semiconductor laser. A method of exciting a laser oscillator of 1.52 μm band. 5. An excitation power (P1) having an excitation wavelength selected from a wavelength range of 0.65 to 0.75 μm and a wavelength of 1.3.
The ratio (R) of the excitation power (P2) of the excitation wavelength selected from the range of 5 to 1.45 μm is R = P1 / (P1 + P
2) When represented by × 100%, the power ratio is 0% <
The 1.4 to 1.52 [mu] m according to any one of claims 1 to 4, wherein R is in the range of 82.5%.
A method for exciting a band optical amplifier or a method for exciting a 1.4 to 1.52 μm band laser oscillator.