CN105591272B - One kind generating high-energy vectors orphan's rain device based on thulium-doped fiber laser - Google Patents

One kind generating high-energy vectors orphan's rain device based on thulium-doped fiber laser Download PDF

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CN105591272B
CN105591272B CN201610152779.8A CN201610152779A CN105591272B CN 105591272 B CN105591272 B CN 105591272B CN 201610152779 A CN201610152779 A CN 201610152779A CN 105591272 B CN105591272 B CN 105591272B
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microns
optical fiber
pumping
orphan
thulium
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CN105591272A (en
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张新陆
王丰
崔金辉
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Harbin Engineering University
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Harbin Engineering University
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    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01SDEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S3/00Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
    • H01S3/10Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating
    • H01S3/10061Polarization control
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01SDEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S3/00Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
    • H01S3/10Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating
    • H01S3/10038Amplitude control
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01SDEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S3/00Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
    • H01S3/10Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating
    • H01S3/11Mode locking; Q-switching; Other giant-pulse techniques, e.g. cavity dumping
    • H01S3/1106Mode locking
    • H01S3/1112Passive mode locking
    • H01S3/1115Passive mode locking using intracavity saturable absorbers
    • H01S3/1118Semiconductor saturable absorbers, e.g. semiconductor saturable absorber mirrors [SESAMs]; Solid-state saturable absorbers, e.g. carbon nanotube [CNT] based

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  • Electromagnetism (AREA)
  • Engineering & Computer Science (AREA)
  • Plasma & Fusion (AREA)
  • Optics & Photonics (AREA)
  • Chemical & Material Sciences (AREA)
  • Materials Engineering (AREA)
  • Nanotechnology (AREA)
  • Lasers (AREA)

Abstract

The invention belongs to light lasers and matter interaction field, more particularly to a kind of thulium-doped fiber laser that is based on to generate high-energy vectors orphan's rain device.One kind generating high-energy vectors orphan's rain device based on thulium-doped fiber laser, passive mode-locking fiber laser 1-10 including compound saturated absorbing body, 2 micron optical fiber Polarization Controllers 11, 2 microns of polarization beam apparatus 12, the passive mode-locking fiber laser of the compound saturated absorbing body includes along the sequentially connected pumping source of light path 1, multimode pumping bundling device 2, double clad mixes thulium single mode optical fiber 3, multimode pumping bundling device 4, pumping source 5, optical element 6, 2 microns of Polarization Controllers 7, coupler 8, isolator 9, 2 microns of transmission single-mode fibers 10 constitute annular chamber, coupled output is sequentially connected Polarization Controller 11, cross-polarization beam splitter 12.The configuration of the present invention is simple, high conversion efficiency can be widely applied to the fields such as medical treatment, military, laser radar and environment measuring.

Description

One kind generating high-energy vectors orphan's rain device based on thulium-doped fiber laser
Technical field
The invention belongs to light lasers and matter interaction field, more particularly to a kind of thulium-doped fiber laser that is based on to generate High-energy vectors orphan's rain device.
Technical background
In the latest 20 years, the basic research of mode locked fiber laser obtains fast-developing, and optical fiber laser is nonlinear system System, when optical pulse intensity is higher, nonlinear effect clearly, can influence the performance of optical fiber laser, wherein including just more The generation of soliton pulse.The high-order harmonic wave mode locking in more soliton states can be utilized to obtain the pulse of high repetition frequency.Due to peak value Clamping effect and Energy Quantization effect, laser can get more soliton pulses when pump power is higher, and based on non-thread Property polarization rotation mode locking and saturated absorbing body mode locking on the basis of carried out a large amount of research.Wherein, orphan's dynamic studies are people One of the hot issue studied.Orphan's rain may be considered a kind of state being between continuous wave and stable mode-locking, cry " weak Mode locking " can also be considered as one kind in more orphan's states, but different from fettering more orphans.Mobile orphan is most of Amplification from continuous wave mode and shaping.As shown in Figure 1, orphan's rain includes three Partial Features:Orphan concentrates, the shifting of orphan It is dynamic, fetter orphan.Mobile orphan moves along a direction and speed to constraint orphan.Under the similar constraint orphan of this phenomenon Orphan's rain, orphan's rain is exactly a kind of intermediate state before mode locking is formed, the research for it, and the orphan for being beneficial to mode locking is dynamic Step response is analyzed.Document S.ChouliandP.Grelu, Opt.Express.2009,1714), pp.11776-11781. reports More orphan's movements are had studied based on Er-doped fiber nonlinear polarization rotation laser with active-passive lock mould.Subsequently, based on graphene mode locking Erbium doped fiber laser SongYF, LiL, ZhangH, Opticsexpress.2013,218), pp.10010-10018 is non-linear Polarize passive mode-locking the ytterbium-doping optical fiber laser BaoC, XiaoX, YangC.Opt.lett.2013,3811 of rotation), pp.1875- 1877. have inquired into orphan's dynamic problem.However, they, which work, concentrates on ytterbium-doping optical fiber laser and erbium doped fiber laser, I One double clad based on the dilute molybdenum disulfide composite material of graphite of experimental construction mix thulium annular chamber passive mode-locking optical-fiber laser Device, the mode locked fiber laser is using the dilute molybdenum disulfide composite material of graphite as saturable absorber.The dilute molybdenum disulfide of graphite is compound Material has recovery time very fast about hundreds of femtosecond) and light injury threshold it is high, 2000nm near-infrared laser pulses are with more relatively strong Nonlinear optical effect and more excellent ultra-wide band saturated absorption.The advantages of this mode locked fiber laser is:It 1, can be with It realizes near 2 microns and human eye safe waveband observes vector orphan's rain;2, it when observing vector orphan's rain, need not adjust Whole pump power and intracavitary state, so that it may which realization controls orphan's displacement speed, and can control pulse strength;3 It is simple and both-end pumping technology improves transfer efficiency using ring resonator structure;4, double clad mixes thulium single mode optical fiber and 2 microns Transmission single-mode fiber can realize high energy pulse output.
Invention content
The object of the present invention is to provide a kind of realizations to observe high-energy vectors orphan's rain in 2 microns of human eye safe wavebands, To realize soliton pulse intensity controlled, and produced based on thulium-doped fiber laser to what orphan's displacement speed was controlled Raw high-energy vectors orphan's rain device.
The object of the present invention is achieved like this:
One kind generating high-energy vectors orphan's rain device based on thulium-doped fiber laser, includes the quilt of compound saturated absorbing body Dynamic mode locked fiber laser 1-10,2 11,2 microns of micron optical fiber Polarization Controller polarization beam apparatus 12, the compound saturated absorption The passive mode-locking fiber laser of body includes along the sequentially connected pumping source 1 of light path, and multimode pumping bundling device 2, double clad is mixed Thulium single mode optical fiber 3, multimode pumping bundling device 4, pumping source 5,6,2 microns of Polarization Controllers 7 of optical element, coupler 8, isolation 9,2 microns of transmission single-mode fibers 10 of device constitute annular chamber, and coupled output is sequentially connected Polarization Controller 11, cross-polarization beam splitting Device 12.
Single orphan's maximum peak power of the passive mode-locking fiber laser of the compound saturated absorbing body is more than 20,000 Watt.
The pump wavelength of the described pumping source output corresponds to the absorption peak of thulium-doped silica fib, respectively 750 nanometers To 820 nanometers, single pump power output is more than 10 watts.
The optical element 6 is the compound saturable absorber of the dilute molybdenum disulfide of graphite, using pulsed laser deposition legal system It is standby, the dilute molybdenum disulfide material of graphite is attached to one section and draws cone treated optical fiber evanescent field side, and couples access resonant cavity Interior formation.
The double clad mixes thulium single mode optical fiber 3, and core diameter is from 10 microns to 40 micron, and cladding diameter is from 130 microns To 400 microns.
The 2 micron optical fiber Polarization Controllers 11 control orphan's displacement speed of two polarized orthogonals.
The beneficial effects of the present invention are:
Compared with prior art, the present invention realizes 2 microns and observes high-energy vectors orphan's rain, by Polarization Control The adjusting of device 11, in the case where not changing intracavitary state status, to realize soliton pulse intensity controlled, and to orphan's displacement Speed is controlled.The especially realization and reproduction of orphan's rain all has good stability.The configuration of the present invention is simple, conversion It is efficient, it can be widely applied to the fields such as medical treatment, military, laser radar and environment measuring.
Description of the drawings
Fig. 1 is orphan's rain schematic diagram.
Fig. 2 is that the present invention is based on the devices that thulium-doped fiber laser generates high-energy vectors orphan's rain.
Specific implementation mode
The present invention is described in detail below in conjunction with drawings and examples.
It is high that the present invention provides a kind of double clad thulium-doped fiber laser generation based on the dilute molybdenum disulfide composite material of graphite The method and its device of energy vectors orphan's rain comprising:The passive mode-locking optical-fiber laser of the dilute molybdenum disulfide composite material of graphite Device, 2 micron optical fiber Polarization Controller, 11,2 microns of polarization beam apparatus 12.
The passive mode-locking fiber laser of the compound saturated absorbing body is two pumping sources 1,5, two bundling devices point Not Wei bundling device 2 and bundling device 4, isolator 9, optical fiber polarization controller 7, optical element 6,20:80 coupler 8 and 2 is micro- The optical fiber 10 of rice transmission single-mode fiber;
The pumping source, bundling device, isolator, optical element, coupler, 2 microns of transmission single-mode fibers and double clad are mixed Thulium optical fiber constitutes annular chamber, and pumping source 1 connects the input terminal of bundling device 2;The output end of bundling device 2 connects double clad thulium doped fiber 3,3 other end of double clad thulium doped fiber is connected with the output end of bundling device 4, and the signal end of bundling device 2 is sequentially connected 2 microns of biographies Defeated single mode optical fiber 10, isolator 9 is finally 80% output end of coupler 8, and the input terminal of coupler is sequentially connected polarization control Device 7 processed, optical element 6, the signal end of bundling device 4,20% output end are connected to Polarization Controller 11 and cross-polarization beam splitter 12。
The double clad thulium doped fiber 3, core diameter is from 10 microns to 40 micron, and cladding diameter is from 130 microns to 400 Micron.
The bundling device 2,4 is multimode pumping bundling device.
The optical element 6 is the carrying dilute molybdenum disulfide composite material saturable absorber of graphite, when having recovery Between very fast and single pulse energy it is high and have many advantages, such as stronger nonlinear optical effect.
The Polarization Controller 7 is 2 micron optical fiber Polarization Controllers, to optic fiber ring-shaped cavity compensating polarizing dispersion.
The polarization beam apparatus 12 is the dynamic-soliton that orphan's rain is decomposed to two polarized orthogonals.
The Polarization Controller 11 is 2 micron optical fiber Polarization Controllers, controls pulse strength and orphan's displacement speed Degree.
Embodiment generates the device structure of high-energy vectors orphan's rain.
As shown in Fig. 2, 793nm pumping sources 1 connect the pumping input terminal of multimode pumping bundling device 2;Multimode pumping is closed The output end of beam device 2 connects 14 meters thulium doped fiber one end;The thulium doped fiber other end connects the output of multimode pumping bundling device 4 End;793nm pumping sources 5 connect the pumping input terminal of multimode pumping bundling device 4;The signal end of multimode pumping bundling device 2 according to 10,2 microns of unrelated isolators 9 of polarization of secondary 2 microns of transmission single-mode fibers for being connected to 10 meters, are finally 2 microns of couplers 8 80% output end, the input terminals of 2 microns of couplers are sequentially connected 2 microns of Polarization Controllers 7, saturated absorption bulk optical element 6, The signal end of multimode pumping bundling device 4,20% output end are connected to 2 microns of Polarization Controllers 11 and 2 microns of cross-polarizations point Beam device 12.Entirely with two pumping sources, two bundling devices, double clad thulium doped fiber, single mode optical fiber, isolator, optical element, inclined Shake controller, coupler, Polarization Controller and polarization beam apparatus is constituted, and realizes the passive mode-locking pulse of compound saturated absorbing body Output, pulse laser are exported by 20% output end of coupler, and 20% output end is connected to Polarization Controller and polarization beam splitting Device.When by adjusting Polarization Controller 7 and corresponding pump power, available orphan's rain is as shown in Figure 1, inclined by adjusting Shake controller 11 and cross-polarization beam splitter 12 realize it is controllable to the orphan's displacement speed and pulse strength of orphan's rain.

Claims (1)

1. one kind generating high-energy vectors orphan's rain device based on thulium-doped fiber laser, include the quilt of compound saturable absorber Dynamic mode locked fiber laser (1-10), the 2nd 2 micron optical fiber Polarization Controller (11), 2 microns of cross-polarization beam splitters (12), It is characterized in that:The passive mode-locking fiber laser of the compound saturable absorber includes along sequentially connected first pumping of light path Source (1), the first multimode pumping bundling device (2), double clad mix thulium single mode optical fiber (3), and the second multimode, which pumps, uses bundling device (4), Second pumping source (5), optical element (6), the one 2 micron of Polarization Controller (7), 2 microns of couplers (8), 2 microns of polarizations are unrelated Isolator (9), 2 microns of transmission single-mode fibers (10), wherein first pumping source (1), the first multimode pumping conjunction beam Device (2), the double clad mix thulium single mode optical fiber (3), the second multimode pumping bundling device (4), second pumping source (5), the optical element (6), the one 2 micron of Polarization Controller (7), 2 microns of couplers (8), described 2 microns partially Shake unrelated isolator (9), and 2 microns of transmission single-mode fibers (10) constitute annular chamber, the coupling output of 2 microns of couplers (8) End is sequentially connected the 2nd 2 micron optical fiber Polarization Controller (11), the passive mode-locking optical fiber of the compound saturable absorber Single orphan's maximum peak power of laser is more than 20 kilowatts;
First pumping source (1) and the pump wavelength of second pumping source (5) output, which correspond to, mixes thulium quartz light Fine absorption peak, respectively 750 nanometers to 820 nanometers, single pump power output is more than 10 watts;
The optical element (6) is the compound saturable absorber of the dilute molybdenum disulfide of graphite, is prepared using pulsed laser deposition method, The dilute molybdenum disulfide material of graphite is attached to one section and draws cone treated optical fiber evanescent field side, and couples shape in access resonant cavity At;
The double clad mixes thulium single mode optical fiber (3), core diameter from 10 microns to 40 micron, cladding diameter from 130 microns to 400 microns;
The 2nd 2 micron optical fiber Polarization Controller (11) controls orphan's displacement speed of two polarized orthogonals; First pumping source of 793nm connects the pumping input terminal of the first multimode pumping bundling device;First multi-mode pump The double clad that the output end of Pu bundling device connects 14 meters mixes thulium single mode optical fiber one end;The double clad mixes thulium single mode optical fiber The other end connects the output end of the second multimode pumping bundling device;Second pumping source connection described second of 793nm The pumping input terminal of multimode pumping bundling device;The signal end of the first multimode pumping bundling device is sequentially connected 10 meters 2 microns of transmission single-mode fibers, the unrelated isolator of 2 microns of polarizations are finally 80% output of 2 microns of couplers The input terminal at end, 2 microns of couplers is sequentially connected the one 2 micron of Polarization Controller, and the compound saturable is inhaled 20% output end of acceptor, the signal end of the second multimode pumping bundling device, 2 microns of couplers is connected to described 22 microns of Polarization Controllers and 2 microns of cross-polarization beam splitters;It is entire described based on thulium-doped fiber laser generation high energy Measure vector orphan's rain device first pumping source, second pumping source, first multimode pumping bundling device, described Second multimode pumping bundling device, the double clad mix thulium single mode optical fiber, 2 microns of transmission single-mode fibers, it is described 2 microns partially Shake unrelated isolator, the compound saturable absorber, the one 2 micron optical fiber Polarization Controller, it is described 2 microns coupling Device, the 2nd 2 micron optical fiber Polarization Controller and 2 microns of cross-polarization beam splitters are constituted, and realize that compound saturable is inhaled The output of the passive mode-locking pulse of acceptor, pulse laser are exported by 20% output end of 2 microns of couplers, 20% output End is connected to the 2nd 2 micron optical fiber Polarization Controller and 2 microns of cross-polarization beam splitters;By adjusting described first 2 micron optical fiber Polarization Controllers and corresponding pump power obtain orphan's rain, then by adjusting the 2nd 2 micron optical fiber polarization control Device processed and 2 microns of cross-polarization beam splitters are realized controllable to the orphan's displacement speed and pulse strength of orphan's rain.
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