CN101464609A - Production method of double-pump wavelength-adjustable broad band full-wavelength converter - Google Patents

Abstract

The invention relates to a method for manufacturing a dual pump wavelength broadband-adjustable all-optical wavelength converter in the technical field of optical communication. The invention chooses a Z-cutting lithium niobate wafer with a mg doping molar ratio of 3 to 7 percent; firstly, a Ti-diffused waveguide structure is manufactured on a minus Z surface of the wafer; then a periodic optical superlattice with a periodic range of 20 to 25Mum is manufactured on a plus Z surface of the wafer, that is, through conducting a room temperature electrical-poling on the wafer, periodic inversion of a wafer polarization domain is achieved; two pumping sources are adopted; and a polarization controller is arranged in front of the wafer to control that the polarization characteristics of pumping light and signal light are ordinary light, so that the dual pump wavelength broadband-adjustable all-optical wavelength converter is acquired. On the premises that the conversion efficiency is not reduced and a wavelength conversion output spectrum is not changed, the method realizes N multiplying M wavelength path conversion of an ultra-wideband, thereby achieving network dynamic reconfiguration and the broadcasting function of a wavelength router.

Description

The method for making of double-pump wavelength-adjustable broad band full-wavelength converter

Technical field

What the present invention relates to is the Wavelength conversion devices method for making in a kind of optical communication technique field, and specifically, what relate to is a kind of method for making of double-pump wavelength-adjustable broad band full-wavelength converter.

Background technology

Existing Wavelength conversion devices, mainly contain the cross-gain modulation of based semiconductor image intensifer (SOA) and cross-phase modulation wavelength converter, Mach-Zehnder wavelength shifter, but all there is incomplete transparent translation in they to amplitude, frequency and the phase place of input signal; And based on SOA or passive wave guide, though be transparent fully full light conversion as the four-wave mixing of optical fiber, because it is the third-order non-linear process, so there is the low problem of conversion efficiency; This in addition wavelength shifter noise is big, causes easily and crosstalks, and its application is limited.Generally speaking, the second nonlinear process is more much higher than three rank process efficiencies, so the difference frequency in based semiconductor (as AlGaAs) or the ferroelectric crystal waveguiding structure or the wavelength shifter of cascading, becomes the developing direction of broad band full wavelength shifter gradually.To information transparency, it only is a pure two-phonon process, has overcome the speed bottle-neck of electro-optical device based on the All Optical Wave Converter part of second nonlinear difference frequency or cascading; In addition, it also possesses low noise, wide adjusting wavelength coverage and can change the characteristics of multi-wavelength simultaneously.Based semiconductor or ferroelectric domain counter-rotating waveguide difference frequency or cascade wavelength shifter are the bright schemes of unique full impregnated, have remarkable advantages with other wavelength shifter scheme ratio.And compare with the wavelength shifter based on beat effect based on the wavelength shifter of cascading, pumping wavelength has solved the waveguide transmission mode problem still at 1.5 μ m communication bands, and can obtain wideer bandwidth.Though the existing demonstration of the difference frequency wavelength shifter of based semiconductor (as AlGaAs), having difficulties at present is the phase matching that is difficult to realize two-beam, owing to the scattering loss of waveguide, all causes conversion efficiency low, thereby uses less at present in addition.

At present, wavelength Conversion phase-matching condition based on periodically poled lithium niobate (PPLN) waveguide has greatly suppressed crosstalking of multi-wavelength interchannel, making becomes the technology of present unique energy realization group wavelength Conversion based on the wavelength shifter of periodic polarized lithium niobate waveguide, also be unique All Optical Wavelength Conversion technology that can realize N * M broadcast capability.The secondary cascading used based on the wavelength shifter of periodic polarized lithium niobate waveguide is divided into two classes: the one, and single pumping frequency multiplication and difference frequency cascading; The 2nd, double pumping action and frequency and difference frequency cascading.

Find through literature search prior art, Chinese patent " method for making of wavelength regulatable broadband full optical wave length converter " (patent No.: ZL 2,005 1 0027943.4) belongs to single pumping frequency multiplication and difference frequency cascading, there is following shortcoming: the one, the frequency multiplication nonlinear factor is little, need very high pumping light power just can obtain considerable conversion efficiency, be not inconsistent with desired low pumping threshold in the optical communication; The 2nd, flashlight and convert light are distributed in the pump light both sides, therefore have at least a wavelength channel occupied, are unfavorable for making full use of of communication band; Moreover in single pumping wavelength conversion plan, when signal light wavelength leveled off to the pump light wavelength, depression can appear in conversion efficiency, therefore had to give up near some channels of pump light wavelength.

Also find in the retrieval, people such as C.Q.Xu were at " Optics Letters " (29 in 2004,2004) go up " Cascaded wavelength conversions based on sum-frequency generation anddifference-frequency generation " (" based on frequently and the wavelength Conversion of difference frequency cascading ") literary composition, this article has been introduced in the periodicity quasi-phase-matching crystals, compare with the cascade of frequency multiplication difference frequency, with frequency difference frequently level be associated with an advantage: once be each pumping light power of double pumping action only need single pumping light power half can obtain same conversion efficiency, reduced power threshold; Two is that two pump light wavelength can be chosen in the both sides of communication band, thereby the wave band in the middle of vacating is used.Set forth in this article be based on the EEE arrowband and frequently with the wavelength Conversion of difference frequency, EEE and frequently being meant participate in and two pump lights frequently and and frequently light all be with non-ordinary light in the PPLN crystal, i.e. E light (Extraordinary) incident or propagation.The flashlight of this narrowband wavelength conversion has big bandwidth, and two pumping wavelength differences can be very big, but the bandwidth of pumping wavelength is minimum, has only 0.6nm.That is to say, PPLN waveguide for period demand, two pump light wavelength must be set in the wavelength place with this cycle coupling (promptly satisfying phase-matching condition), each flashlight in the respective signal bandwidth can only be exported a convert light, if the pump light wavelength has drift slightly, just do not produce with frequency light probably, also just do not have convert light output, this has limited the flexible Application of wavelength shifter greatly.

Summary of the invention

The objective of the invention is to overcome the deficiencies in the prior art, a kind of method for making of double-pump wavelength-adjustable broad band full-wavelength converter is provided, utilize in the periodicity optical superlattices and frequently with the second-order optical nonlinearity effect of difference frequency cascade, adopt the pumping light wave that two power can be lower, has wavelength-tunable, bandwidth is wideer, and signal light wavelength can be operated in the communication C-band, the advantage that Power penalty is low.

The present invention is achieved by the following technical solutions, the present invention includes following steps:

The first step, the magnesium doping mol ratio of selecting a Z cutting is 3%-7% lithium niobate crystal chip, on this wafer-Z face, make titanium diffused waveguide structure, on this wafer+Z face, make then and have the periodicity optical superlattices that periodic regime is 20-25 μ m, promptly by wafer is carried out the room temperature electric field polarization, to realize the periodic inversion on crystal polarization farmland;

Second step, adopt two pump light sources, be ordinary light by Polarization Controller is set before wafer with the polarization characteristic of controlling pump light and flashlight, promptly obtain this double-pump wavelength-adjustable broad band full-wavelength converter.

Described room temperature electric field polarization, the specific implementation step is as follows:

1. select a kind of dielectric, this dielectric is a kind of growing up in growth course along the ferroelectric single domain crystal of Z direction spontaneous polarization, and is that the doping mol ratio is 3%-7% magnesium-doped lithium niobate (MgO:LiNbO ₃), along this dielectric Z direction (optical axis c direction) cutting, the thickness of the magnesium-doped lithium niobate crystal under the cutting is 0.2mm-1mm, and upper and lower surface is parallel and all polished, and the normal direction of upper and lower surface is the spontaneous polarization direction of crystal;

2. the titanium diffusion technique is used on this wafer-Z surface, promptly under 1130 ℃ high temperature, led to argon gas tens hours, diffusion is more than 1 hour behind the logical oxygen, be to diffuse into magnesium-doped lithium niobate substrate in the titanium bar of 2-8 μ m with the width of-pre-sputter of Z face, form a ducting layer, the feature of this waveguide is that the guided wave of transverse electric wave (TE) and transverse magnetic wave (TM) pattern all can be excited;

3. use photoetching technique then, promptly at first apply the photoresist of a bed thickness 1 μ m, after exposure, development, obtain periodically grating fringe in twin polishing crystal+Z surface rotation; And then sputter one bed thickness is the conduction aluminium lamination of 0.1 μ m on photoresist, and is again that the gained sample is ultrasonic with acetone, so just formed the array metal grating electrode of the long aluminum strip formation of one-period property on sample.

The periods lambda of metal grating electrode is:

$\mathrm{\Λ}={(\frac{N_{\mathrm{effSF}}^e}{{\mathrm{\λ}}_{\mathrm{SF}}}-\frac{N_{\mathrm{effp}1}^o}{{\mathrm{\λ}}_{p1}}-\frac{N_{\mathrm{effp}2}^o}{{\mathrm{\λ}}_{p2}})}^{-1}---\left(a\right)$

λ in the formula _i(i=P ₁, P ₂, SF) be respectively pump light 1, pump light 2 and frequency light wavelength, wherein

${\mathrm{\λ}}_{\mathrm{SF}}={(\frac{1}{{\mathrm{\λ}}_{p1}}+\frac{1}{{\mathrm{\λ}}_{p2}})}^{-1}$

---the effective refractive index of the non-ordinary light of ripple in the waveguide and frequently;

---the effective refractive index of pumping wave 1,2 ordinary lights in the waveguide;

For dutycycle is the periodic structure of 1:1, and the length l of electrode is half of cycle, i.e. l=Λ/2 in each cycle; For dutycycle is the periodic structure of 1:2, and the length of electrode is 1/3 of the cycle in each cycle, i.e. l=Λ/3;-Z face plating plane electrode.

4. in the room temperature electric field polarization process, in the zone, farmland that electrode is arranged, thereby the coercive field that utilizes high-voltage electric field to overcome crystals makes the spontaneous polarization direction of this electricdomain reverse; Zone, electrodeless farmland, the polarised direction of its electricdomain still keeps original direction.

Polarization method of the present invention can adopt prior art, the present invention adopts two pump light sources, utilize non-linear OOE and frequently process realize wavelength Conversion, by Polarization Controller is set before wafer, be ordinary light (O light) in the crystal with the polarization characteristic of control pump light and flashlight.Two pump light sources of the present invention are generally fixed one of them pump light wavelength, and an other pump light wavelength changes in pump-bandwidth, to realize the many convert light outputs to same flashlight.Two pump light source wavelength also can be regulated simultaneously.

The present invention is based on broadband OOE and the wavelength Conversion design of frequency with the difference frequency cascading, OOE is meant that with frequency participation and two pump lights frequently are the ordinary light in the crystal herein, and promptly O light (Ordinary) and frequency light then are non-ordinary light (E light).Polarization state is to regulate by the Polarization Controller that is provided with before wafer.The present invention inherit above-mentioned EEE arrowband and frequently with the advantage of difference frequency wavelength Conversion in owing to adopt broadband OOE and frequently, two pump light wavelength are adjustable, and on-fixed, promptly can flexible two pump light wavelength.Like this, signal light wavelength changes in signal bandwidth, also can regulate the pump light wavelength simultaneously and change in pump-bandwidth---promptly corresponding input signal light, get the M of arbitrary pump light wavelength in a pump-bandwidth wavelength, and just can realize M convert light output.If N flashlight input arranged in signal bandwidth, M pumping wavelength in the adjusting pump-bandwidth freely just can be realized N * M convert light output neatly.

The invention has the beneficial effects as follows:

1, adds in the titanium diffused waveguide structure at mg-doped lithium niobate, employing is different from the cycle design of frequency multiplication difference frequency cascading, make in the wavelength-conversion process, can adopt two pumping light waves, two pumping light powers only need half of fundamental frequency pumping light power in single pumping concatenated schemes, just can realize identical conversion efficiency; Power penalty is low, and has overcome the conversion depression that can occur when signal light wavelength is tending towards fundamental light wave length;

2, two pumping wavelengths can be chosen in the both sides of communication band, can avoid taking the middle wavelength of communication band, help making full use of the fiber bandwidth resource;

3, do not reducing conversion efficiency and do not changing under the prerequisite of wavelength Conversion output spectra, can realize wideer than former frequency multiplication difference frequency concatenated schemes broadband, the N that power threshold is lower * M wavelength channel conversion, thus realize the dynamic reorganization of network and the broadcast capability of wavelength route.

Description of drawings

Fig. 1 is the antetype device synoptic diagram of the embodiment of the invention based on the N * M broad band full wavelength shifter of MgO:PPLN waveguiding structure.

Embodiment

Below in conjunction with accompanying drawing embodiments of the invention are elaborated.Present embodiment is being to implement under the prerequisite with the technical solution of the present invention, provided detailed embodiment and concrete operating process, but protection scope of the present invention is not limited to following embodiment.

Embodiment 1

The first step, the magnesium doping mol ratio of selecting a Z cutting is 3%-7% lithium niobate crystal chip, at first on this wafer-Z face, make titanium diffused waveguide structure, on this wafer+Z face, make then and have the periodicity optical superlattices that periodic regime is 20-25 μ m, promptly by wafer is carried out the room temperature electric field polarization, to realize the periodic inversion on crystal polarization farmland; Specific as follows:

(1) choosing size is 20 * 10 * 1mm, and promptly thickness is the Z cutting mg-doped lithium niobate wafer of the 5%mol doping ratio of 1mm ,+/-the Z face all polishes.

(2) make the bar waveguide that a width is 6 μ m at-Z face with the titanium diffusion technique;

(3) forming one-period on+Z surface with photoetching method is 20.4 μ m, wide by 8 μ m, the array positively charged metal utmost point (supposing that dutycycle is 8: 12.4) that 10mm is long.The grating cycle is the Sellmier equation substitution formula with 36.3 ℃ of following mg-doped lithium niobates $\mathrm{\Λ}={(\frac{N_{\mathrm{SF}}^e}{{\mathrm{\λ}}_{\mathrm{SF}}}-\frac{N_{p1}^o}{{\mathrm{\λ}}_{p1}}-\frac{N_{p2}^o}{{\mathrm{\λ}}_{p2}})}^{-1}$ Gained is wherein established λ _P1=1.570 μ m, λ _P2=1.546 μ m.

(4) according to polarization method described in the Chinese patent 200510027943.4 magnesium-doped lithium niobate crystal is polarized.In the room temperature electric field polarization process, in the zone, farmland that electrode is arranged, thereby the coercive field that utilizes high-voltage electric field to overcome crystals makes the spontaneous polarization direction of this electricdomain reverse; Zone, electrodeless farmland, the polarised direction of its electricdomain still keeps original direction.

So far, obtained 5% magnesium doping ratio, there is the periodic polarized lithium niobate crystal chip of titanium diffusion bar waveguiding structure on the surface, its size is 20 * 10 * 1mm, the grating cycle is Λ=20.4 μ m.

Second step, adopt two pump light sources, be ordinary light by Polarization Controller is set before wafer with the polarization characteristic of controlling pump light and flashlight, promptly obtain this double-pump wavelength-adjustable broad band full-wavelength converter.

In theory, the lithium niobate crystal chip that the first step obtains can be realized natural breadth bandgap wavelength conversion under 36.3 ℃, the fixing wavelength of pumping 2, when the wavelength of pump light 1 respectively at 1.57 μ m and 1.55 μ m places, the wavelength shifter of this cycle parameter can realize and frequently the pumping 2 optical wavelength bandwidth in the process be respectively 47nm and 56nm; And behind the input signal light and frequently light with flashlight difference frequency process is and the inverse process of frequency in fact, so signal bandwidth and pump-bandwidth have relation of equivalence.

Wavelength Conversion with one 8 (signal light-wave long-channel) * 2 (pump light wavelength channel) is an example below, enter waveguide with communication C-band wavelength signals TE mould polarization, utilize E light polarization and frequency light to make pump light again, carry out the difference frequency process with required conversion communication band flashlight; As can be seen, can realize in the adjustable wide-band wavelength shifter structure of made that it is more than the 45nm that pumping wavelength is regulated bandwidth, the signal wavelength bandwidth has the ultra broadband wavelength Conversion function of broadcast capability greater than 50nm.

As shown in Figure 1, be synoptic diagram based on the antetype device of the All Optical Wave Converter of the N * M of this MgO:PPLN (oo-e) wafer.One of pump light is fixing, and one adjustable, and two pump lights all are adjusted to ordinary light (O light) by Polarization Controller; Input signal light is from different local light carriers, be adjusted to ordinary light by Polarization Controller after, enter to be coupled in the optical fiber behind the wavelength division multiplexer and transmit; Pump light and flashlight enter the MgO:PPLN crystal waveguide structure in the temperature adjustable temperature stove after the coupling mechanism coupling, emergent light can obtain the convert light output of a series of correspondences through separation vessel.Mg-doped lithium niobate waveguide wafer temperature is set at 36.3 ℃ by temperature control furnace.

According to International Telecommunications Union's standard, input signal light wavelength λ ₁, λ ₂..., λ _S1547.32,1548.12,1548.92,1549.72,1550.52,1551.32,1552.12,1552.92nm, the fixedly wavelength X of pump light 2 get 8 wavelength of C-band: _P2Be 1570.42nm, pump light 1 λ _P1a, λ _P1bChoose 2 wavelength: 1545.72nm and 1543.73nm in its pump-bandwidth, then can obtain convert light λ _1a, λ _1b..., λ _Sa, λ _Sb1568.77,1567.95,1567.13,1566.72,1566.31,156590,1565.50,1565.09,1564.68,1564.27,1563.87,1563.45,1563.06,1562.64,1561.83,1561.02nm have 16:.And then carry out the network system test of every performance, and realizing not having and crosstalk, more than the 160Gbit/s, the bit error rate (BER) is less than 10E-10,8 * 2 the wavelength Conversion with broadcast capability of 100GHZ-50GHZ.

Embodiment 2

The first step, the magnesium doping mol ratio of selecting a Z cutting is 3%-7% lithium niobate crystal chip, at first on this wafer-Z face, make titanium diffused waveguide structure, on this wafer+Z face, make then and have the periodicity optical superlattices that periodic regime is 20-25 μ m, promptly by wafer is carried out the room temperature electric field polarization, to realize the periodic inversion on crystal polarization farmland; Specific as follows:

(1) choosing size is 20 * 10 * 1mm, and promptly thickness is the Z cutting mg-doped lithium niobate wafer of the 7%mol doping ratio of 1mm ,+/-the Z face all polishes.

(2) make the bar waveguide that a width is 6 μ m at-Z face with the titanium diffusion technique;

(3) forming one-period on+Z surface with photoetching method is 23.4 μ m, wide by 8 μ m, the array positively charged metal utmost point (supposing that dutycycle is 8: 12.4) that 10mm is long.The grating cycle is the Sellmier equation substitution formula with 24.2 ℃ of following mg-doped lithium niobates $\mathrm{\Λ}={(\frac{N_{\mathrm{SF}}^e}{{\mathrm{\λ}}_{\mathrm{SF}}}-\frac{N_{p1}^o}{{\mathrm{\λ}}_{p1}}-\frac{N_{p2}^o}{{\mathrm{\λ}}_{p2}})}^{-1}$ Gained is wherein established λ _P1=1.569 μ m, λ _P2=1.533 μ m.

(4) according to polarization method described in the Chinese patent 200510027943.4 magnesium-doped lithium niobate crystal is polarized.In the room temperature electric field polarization process, in the zone, farmland that electrode is arranged, thereby the coercive field that utilizes high-voltage electric field to overcome crystals makes the spontaneous polarization direction of this electricdomain reverse; Zone, electrodeless farmland, the polarised direction of its electricdomain still keeps original direction.

So far, obtained 7% magnesium doping ratio, there is the periodic polarized lithium niobate crystal chip of titanium diffusion bar waveguiding structure on the surface, its size is 20 * 10 * 1mm, the grating cycle is Λ=23.4 μ m.

Second step, adopt two pump light sources, be ordinary light by Polarization Controller is set before wafer with the polarization characteristic of controlling pump light and flashlight, promptly obtain this double-pump wavelength-adjustable broad band full-wavelength converter.

In theory, the lithium niobate crystal chip that the first step obtains can be realized natural breadth bandgap wavelength conversion under 24.2 ℃, the fixing wavelength of pumping 2, when the wavelength of pump light 1 respectively at 1.569 μ m and 1.534 μ m places, the wavelength shifter of this cycle parameter can realize and frequently the pumping 2 optical wavelength bandwidth in the process be respectively 45nm and 53nm; And behind the input signal light and frequently light with flashlight difference frequency process is and the inverse process of frequency in fact, so signal bandwidth and pump-bandwidth have relation of equivalence.

Wavelength Conversion with one 8 (signal light-wave long-channel) * 2 (pump light wavelength channel) is an example, enters waveguide with communication C-band wavelength signals TE mould polarization, utilizes E light polarization and frequency light to make pump light again, carries out the difference frequency process with required conversion communication band flashlight.

As shown in Figure 1, be synoptic diagram based on the antetype device of the All Optical Wave Converter of the N * M of this MgO:PPLN (oo-e) wafer.One of pump light is fixing, and one adjustable, and two pump lights all are adjusted to ordinary light (O light) by Polarization Controller; Input signal light is from different local light carriers, be adjusted to ordinary light by Polarization Controller after, enter to be coupled in the optical fiber behind the wavelength division multiplexer and transmit; Pump light and flashlight enter the MgO:PPLN crystal waveguide structure in the temperature adjustable temperature stove after the coupling mechanism coupling, emergent light can obtain the convert light output of a series of correspondences through separation vessel.Mg-doped lithium niobate waveguide wafer temperature is set at 24.2 ℃ by temperature control furnace.

According to International Telecommunications Union's standard, signal light wavelength λ ₁, λ ₂..., λ _SGet 8 wavelength of C-band: 1536.22,1537.01,1537.79,1538.58,1539.37,1540.16,1540.96,1541.75nm, the fixing wavelength X of pump light 2 wherein _P2Be 1569.61nm, pump light 1 λ _P1a, λ _P1bChoose 2 wavelength: 1533.86nm and 1531.90nm in its pump-bandwidth, then can obtain convert light λ _1a, λ _1b..., λ _Sa, λ _Sb1567.15,1566.33,1565.52,1565.10,1564.70,1564.28,1563.88,1563.47,1563.07,1562.66,1562.24,1561.84,1561.43,1561.03,1560.21,1559.40nm have 16:.And then carry out the network system test of every performance, and realizing not having and crosstalk, more than the 160Gbit/s, the bit error rate (BER) is less than 10E-10,8 * 2 the wavelength Conversion with broadcast capability of 100GHZ-50GHZ.

Because this wavelength shifter is to be made of a ferroelectrics crystal, thickness is the waveguide device of 0.2mm-1mm, so also needs in the practical application to encapsulate by the conventional package technology of optical communication device.

The advantage of present embodiment: the one because and nonlinear factor frequently bigger, each pumping light power of double pumping action only need single pumping light power half just can obtain same conversion efficiency, reduced power threshold; Two is that two pump light wavelength can be chosen in the both sides of communication band, thereby the wave band in the middle of vacating is used.And single pumping wavelength must be set in the middle of the communication band, and depression appears in convert light efficient when signal light wavelength is tending towards pumping wavelength.The 3rd, in the double pumping action wavelength conversion scheme, the wavelength difference between two pump lights, pump light and flashlight, pump light and the convert light can be more relatively large, therefore and bandwidth wideer than frequency multiplication bandwidth.At last, regulate when this method can realize pumping wavelength and signal wavelength, can produce more convert light output.

The necessary wavelength converter requires low pump power in the following optical communication network, high conversion efficiency and big switching bandwith, so, can be used to set up N * M lambda router flexibly based on broadband OOE and the problem that can solve this respect frequently with the wavelength Conversion of difference frequency cascading.

Claims (4)

1. the method for making of a double-pump wavelength-adjustable broad band full-wavelength converter is characterized in that, comprises the steps:

The first step, the magnesium doping mol ratio of selecting a Z cutting is 3%-7% lithium niobate crystal chip, on this wafer-Z face, make titanium diffused waveguide structure, on this wafer+Z face, make then and have the periodicity optical superlattices that periodic regime is 20-25 μ m, by wafer is carried out the room temperature electric field polarization, realize the periodic inversion on crystal polarization farmland;

Second step, adopt two pump light sources, be ordinary light by Polarization Controller is set before wafer with the polarization characteristic of controlling pump light and flashlight, obtain this double-pump wavelength-adjustable broad band full-wavelength converter.

2. the method for making of double-pump wavelength-adjustable broad band full-wavelength converter according to claim 1 is characterized in that described room temperature electric field polarization, and the specific implementation step is as follows:

1. select a kind of dielectric, this dielectric is a kind of growing up in growth course along the ferroelectric single domain crystal of Z direction spontaneous polarization, and be that the doping mol ratio is 3%-7% magnesium-doped lithium niobate, cut along this dielectric Z direction, the thickness of the magnesium-doped lithium niobate crystal under the cutting is 0.2mm-1mm, upper and lower surface is parallel and all polished, and the normal direction of upper and lower surface is the spontaneous polarization direction of crystal;

2. the titanium diffusion technique is used on this wafer-Z surface, promptly under 1130 ℃ high temperature, led to argon gas tens hours, diffusion is more than 1 hour behind the logical oxygen, be to diffuse into magnesium-doped lithium niobate substrate in the titanium bar of 2-8 μ m with the width of the pre-sputter in-Z surface, form a ducting layer, the guided wave of the transverse electric wave of this waveguide and transverse magnetic wave pattern all can be excited;

3. use photoetching technique then, promptly at first apply the photoresist of a bed thickness 1 μ m in twin polishing crystal+Z surface rotation, after exposure, development, obtain periodically grating fringe, and then sputter one bed thickness is the conduction aluminium lamination of 0.1 μ m on photoresist, again that the gained sample is ultrasonic with acetone, so just formed the array metal grating electrode of the long aluminum strip formation of one-period property on sample, the periods lambda of metal grating electrode is:

$\mathrm{\Λ}={(\frac{N_{\mathrm{effSF}}^e}{{\mathrm{\λ}}_{\mathrm{SF}}}-\frac{N_{\mathrm{effp}1}^o}{{\mathrm{\λ}}_{p1}}-\frac{N_{\mathrm{effp}2}^o}{{\mathrm{\λ}}_{p2}})}^{-1}$

λ in the formula _i(i=P ₁, P ₂, SF) be respectively pump light 1, pump light 2 and frequency light wavelength, wherein:

${\mathrm{\λ}}_{\mathrm{SF}}={(\frac{1}{{\mathrm{\λ}}_{p1}}+\frac{1}{{\mathrm{\λ}}_{p2}})}^{-1};$

---the effective refractive index of the non-ordinary light of ripple in the waveguide and frequently;

---the effective refractive index of pumping wave 1,2 ordinary lights in the waveguide;

For dutycycle is the periodic structure of 1:1, and the length l of electrode is half of cycle, i.e. l=Λ/2 in each cycle;

For dutycycle is the periodic structure of 1:2, and the length of electrode is 1/3 of the cycle in each cycle, i.e. l=Λ/3;

-Z surface is the plating plane electrode;

4. in the room temperature electric field polarization process, in the zone, farmland that electrode is arranged, thereby the coercive field that utilizes high-voltage electric field to overcome crystals makes the spontaneous polarization direction in this zone, farmland that electrode is arranged reverse; In zone, electrodeless farmland, the polarised direction of its electricdomain still keeps original direction.

3. the method for making of double-pump wavelength-adjustable broad band full-wavelength converter according to claim 1, it is characterized in that, described two pump light sources, one of them pump light wavelength is fixed, an other pump light wavelength changes in pump-bandwidth, realizes the many convert light outputs to same flashlight; Perhaps two pump light source wavelength can be regulated simultaneously, realize the conversion of N flashlight to M convert light.

4. according to the method for making of claim 1 or 3 described double-pump wavelength-adjustable broad band full-wavelength converters, it is characterized in that, described two pump light sources, its pumping wavelength can be selected the two ends of communication band.