CN101521349A

CN101521349A - White light quantum dot fibre laser

Info

Publication number: CN101521349A
Application number: CN200910097188A
Authority: CN
Inventors: 沈常宇; 王志毅; 金尚忠; 周俊
Original assignee: China Jiliang University
Current assignee: China Jiliang University
Priority date: 2009-03-26
Filing date: 2009-03-26
Publication date: 2009-09-02

Abstract

The invention relates to a white light quantum dot fibre laser which comprises a first fiber grating (1), a semiconductor blue light laser (2), a wavelength division multiplexer (3), quantum dot optical fibre (4), a second fibre grating (5) and a laser output end (6). The signal input end of the wavelength division multiplexer is connected with the first fibre grating (1), the pumping input end is connected with the semiconductor blue light laser, the pumping output end is connected with the quantum dot optical fibre which is connected with the reflection end of the second fibre grating (5), and the transmission end is the laser output end. Because exciting light of different sizes of quantum occurs in different degrees of red shift when a quantum dot is excited by the blue light, quantum dots of different sizes are mixedaccording to a certain proportion in glass optical fibre, therefore, the white light output can be realized. The invention has simple structure and easy fabrication, can realize the white light laser output, and can be widely applied to various fields of the optical fibre technology.

Description

A kind of white light quantum dot fibre laser

Technical field

The present invention relates to a kind of white light quantum dot fibre laser, belong to the fiber laser field, relate in particular to the quantum dot fibre laser field.

Background technology

The general device of the laser of emission white light is comparatively complicated, white light laser need adopt neodymium doped yttrium aluminium garnet laser acquisition 1064nm pulses such as acousto-optic Q modulation, the pump parametric oscillator obtains wavelength 1535nm laser then, by 1064nm and 1535nm laser are carried out and frequently obtain the output of 628nm laser, by 628nm and 1535nm laser are obtained 446nm laser with frequency, by the 1064nm frequency multiplication being obtained 532nm laser, final synthesize white light output.The microstructured optical fibers white light laser generator that proposes as people such as Wang Qingyue needs self-starting mode-locked laser, microstructured optical fibers and a plurality of coupled lens etc. in addition; Wish that the white light laser that generation rather waits the people to propose need adopt the optical superlattice of different structure cascade to produce accurate white light output as nonlinear crystal, complex structure and the ratio that need strictly regulate temperature control RGB light.

White light laser has purposes very widely at aspects such as optical communication, laser spectroscopy, laser biology, optics " light pincers " and illumination amusements continuously, has also established foundation stone for optical information systematic research of future generation simultaneously.

Because the discrete characteristic of energy level of quantum dot and the quantum confinement benefit and the small-size effect of quantum dot, its emission peak can carry out tuning according to the quantum dot size, and this advantage is to make it become the effective means that produces the continuous spectrum white light.Quantum dot is a kind of potential nanoscale semiconductor, has the wide absorption spectrum and the emission spectrum of broad, and can come tuning peak luminous wavelength by its size; Quantum dot has significant technological advantage, compares with traditional generation red, green, blue look fluorescent material, and quantum dot making temperature is lower, and Production Time is also shorter, particularly by tuning quantum dot size, can control its emission wavelength.

Advance optical fiber with different size is quantum dot-doped, excite the different size quantum dot, produce multiple coloured light, constitute reflection cavity by fiber grating by the semiconductor blue laser; The quantum dot fibre laser of realization white light output has simple in structure, is easy to make, can realizes characteristics such as white light laser output, can be widely used in the every field of optical fiber technology.

Summary of the invention

The object of the present invention is to provide a kind of white light quanta point laser.This laser not only can produce broadband, super smooth white light laser, and has characteristics such as simple in structure, that running is stable.

The present invention is achieved through the following technical solutions: comprise first fiber grating, semiconductor blue laser, wavelength division multiplexer, quantum dot-doped optical fiber, second fiber grating and laser output.The signal input part of wavelength division multiplexer connects first fiber grating, pumping input termination semiconductor blue laser, and the quantum dot-doped optical fiber of output termination, quantum dot-doped optical fiber connects the reflection end of second fiber grating again, and the transmission end is a laser output.

Operation principle of the present invention is: the blue light that the semiconductor blue laser sends incides as gain media and the quanta point optical fiber of mixing that produces the multiple coloured light in visible range (red, yellow, green, blue etc.) by wavelength division multiplexer as pump light.The light of different peak wavelengths can take place when blue-light excited in the different size quantum dot, the quantum dot of these different sizes is mixed in the glass optical fiber by a certain percentage, just the visible light of these peak wavelengths can be produced, just continuous, smooth white light can be obtained after the mixing; Through the reflection of two fiber gratings and repeatedly gain, can obtain continuous, super smooth white light laser at laser output.

Description of drawings

Fig. 1 is the schematic diagram of a kind of white light quantum dot fibre laser of the present invention;

The spectrogram of Fig. 2 different size quantum dot when blue-light excited;

Embodiment

With reference to Fig. 1, the device of white light quantum dot fibre laser of the present invention comprises first fiber grating 1, semiconductor blue laser 2, wavelength division multiplexer 3, quantum dot-doped optical fiber 4, second fiber grating 5 and laser output 6.The signal input part of wavelength division multiplexer connects first fiber grating, pumping input termination semiconductor blue laser, and the quantum dot-doped optical fiber of output termination, quantum dot-doped optical fiber connects the reflection end of second fiber grating again, and the transmission end is a laser output.Quantum dot in the wherein quantum dot-doped optical fiber can adopt the CdSe/ZnSe of nucleocapsid structure or the quantum dot of CdSe/ZnS or CdSe/CdS or CdS/ZnS or CdS/HgS.The size of quantum dot is 2nm～6nm scope.First fiber grating is that the resonance wavelength that satisfies of a series of (at least three) is positioned at the broadband Bragg reflector that red, green, blue typical wavelengths Fiber Bragg Grating FBG constitutes, and second fiber grating adopts the chirped fiber grating of a series of (at least three).Fig. 2 describes is that the CdSe/ZnSe quantum dot of different size nucleocapsid structure is subjected to the photoluminescence spectra figure when blue-light excited.As can be seen from the figure, as when blue-light excited, the CdSe/ZnSe quantum dot of nucleocapsid structure size be 2.2,2.7,3.2,3.4,3.7,3.8,4.0 and during 4.8nm respectively emission peak wavelength lay respectively at 510,540,555,580,585,590,595 and 620nm.Therefore, in this example size is respectively that three kinds of nucleocapsid structure CdSe/ZnSe of 2.2nm～3nm and 4nm～5nm and 4nm～5nm scope are quantum dot-doped to advance silica fiber, obtain blue light, green glow and ruddiness, obtain white light after three kinds of coloured light mix, output white light laser behind the feedback oscillator.

Claims

1. white light quantum dot fibre laser, it comprises: first fiber grating (1), semiconductor blue laser (2), wavelength division multiplexer (3), quantum dot-doped optical fiber (4), second fiber grating (5) and laser output (6).The signal input part of wavelength division multiplexer connects first fiber grating, pumping input termination semiconductor blue laser, and the quantum dot-doped optical fiber of output termination, quantum dot-doped optical fiber connects the reflection end of second fiber grating again, and the transmission end is a laser output.

2. a kind of white light quantum dot fibre laser according to claim 1 is characterized in that: the quantum dot of the optical fiber that mixes is the CdSe/ZnSe of nucleocapsid structure or the quantum dot of CdSe/ZnS or CdSe/CdS or CdS/ZnS or CdS/HgS.The size of quantum dot is 2nm～6nm scope.

3. a kind of white light quantum dot fibre laser according to claim 1, it is characterized in that: use fiber grating as reflecting cavity mirror, the interior blue-light excited multiple color of light of multiple size quantum dot emission of binding cavity also is mixed into white light, repeatedly forms the output of white light laser after the feedback.

4. a kind of white light quantum dot fibre laser according to claim 1, it is characterized in that: described first fiber grating is that the resonance wavelength that satisfies of a series of (at least three) is positioned at the broadband Bragg reflector that red, green, blue typical wavelengths Fiber Bragg Grating FBG constitutes, and second fiber grating adopts the chirped fiber grating of a series of (at least three).