CN206340825U - A kind of mode locking semiconductor laser based on multimode interferometric structure - Google Patents
A kind of mode locking semiconductor laser based on multimode interferometric structure Download PDFInfo
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Abstract
The utility model is related to a kind of mode locking semiconductor laser based on multimode interferometric structure, the mode locking semiconductor laser uses slab waveguide structure, ridge waveguide structure or wedge-shaped waveguide structure, gain region, electricity isolated region and saturated absorption area are formed on the waveguiding structure, the electricity isolated region is located between gain region and saturated absorption area, a part for the uptake zone, the electricity isolated region and a part for the gain region constitute multiple-mode interfence area, or a part for the gain region constitutes multiple-mode interfence area.The utility model proposes mode locking semiconductor laser can obtain high-power ultrashort pulse, and make simple, it is integrated beneficial to optics.
Description
Technical field
The utility model is related to a kind of light emitting semiconductor device, and in particular to a kind of locked mode based on multimode interferometric structure half
Conductor laser.
Background technology
Mode locking semiconductor laser (MLLD) is because with good stability, reliability is high, cheap, and can be very wide
Wave-length coverage in the advantages of the moderate subpicosecond pulse of power is provided, therefore in optical communication, high-speed AD converter, light fortune
Important application is obtained in the fields such as calculation, optical interconnection, electro optic sampling.
But the one of mode locking semiconductor laser primary limitation is that its relatively low light power, causes its nothing
Method is applied in the large-scale desk-top laser system of such as dye laser and solid state laser.General mode locking semiconductor laser goes out
Luminous power is in tens milliwatts or so.Additional spatial filter, using the methods such as array structure, rearmounted amplification are verified can be effective
The light power of mode-locked laser is improved, and keeps single transverse mode output.Wedge-shaped waveguide structure such as wedge-shaped gain region, has by increase
The gain area of source region, makes the narrow region of single transverse mode become wide multimode region, so that higher power output is obtained, and with narrow
Waveguide section acts also as the effect of mode filter as saturated absorption area while compression pulse width, suppresses the production of higher order mode ripple
Raw lasing.The subpicosecond pulse of hundreds of milliwatts can be obtained using the mode locking semiconductor laser of wedge-shaped waveguide structure.Therefore, increase
The gain area of active area pattern conduction, can effectively improve the light power of mode locking semiconductor laser.
Utility model content
In order to obtain the ultrashort pulse of high power, narrow spaces, the utility model provides a kind of based on multimode interferometric structure
Mode locking semiconductor laser, technical scheme is as follows.
A kind of mode locking semiconductor laser based on multimode interferometric structure, the mode locking semiconductor laser uses slab waveguide
Structure, ridge waveguide structure or wedge-shaped waveguide structure, form gain region, electricity isolated region and saturated absorption on the waveguiding structure
Area, the electricity isolated region is located between gain region and saturated absorption area, wherein, a part for the uptake zone, the electric isolution
A part for area and the gain region constitutes multimode interferometric structure, or a part for the gain region constitutes multiple-mode interfence knot
Structure.
Further, the total length of the gain region is more than the total length in saturated absorption area.
Further, the length in the multiple-mode interfence area is that multimode waveguide exports the most short coupling that section obtains single imaging
Length.
Further, the gain region includes the first end face of the first strip and the length direction from the first strip
The second strip being located on the axis that axis along its length extends, the second strip is relative to the axis pair
Claim, the width of the second strip is less than the width of the first strip；
The saturated absorption area include the 3rd strip and from the first end face of the length direction of the 3rd strip along its
The 4th strip being located on the axis that the axis of length direction extends, the 4th strip is relative to the axisymmetrical；
The second end face of the remote first end face of the surface of the electricity isolated region side and the first strip of gain region connects
Touch, the surface of relative opposite side is contacted with the second end face of the remote first end face of the 3rd strip in saturated absorption area；
The first strip, the electricity isolated region and the 3rd strip in the saturated absorption area of the gain region structure together
Into the multiple-mode interfence area.
Further, the gain region includes the first strip, the first end face edge from the length direction of the first strip
The second strip being located on the axis that the axis of its length direction extends and from the length direction of the first strip
The 3rd strip being located on the axis that the axis of second end face along its length extends, the second strip and the 3rd length
Bar shaped is both with respect to the axisymmetrical, and second end face is relative with first end face；The width phase of second strip and the 3rd strip
Deng；
Saturated absorption area includes the 4th strip, and the 4th strip is located at the extension of the axis of the first strip length direction
On line, the 4th strip is symmetrical relative to the extended line of the axis, and the width of the 4th strip is equal to the width of the 3rd strip；
The surface of electricity isolated region side and the extension end contact of the 3rd strip of gain region, the table of relative opposite side
The end contact in face and one end of the 4th strip in saturated absorption area；
First strip of the gain region constitutes multiple-mode interfence area.
Further, the gain region includes the first strip, the first end face edge from the length direction of the first strip
The second strip being located on the axis that the axis of its length direction extends, the second strip is relative to the axisymmetrical；
Saturated absorption area includes the 4th strip, and the 4th strip is located at the extension of the axis of the first strip length direction
On line, and relative to the axisymmetrical, or positioned at the first strip length direction axis extended line top or under
Side, but without departing from gain region the first strip remote first end face second end face scope；The width of 4th strip
Equal to the width of the second strip；
The surface of electricity isolated region side is contacted with the second end face of the remote first end face of the first strip of gain region, phase
To opposite side surface and saturated absorption area the 4th strip one end end contact；
First strip of the gain region constitutes multiple-mode interfence area.
Further, size of the electricity isolated region along the length direction of gain region is 5um~10um.
Further, the light output end of gain region is coated with anti-reflection film；End face of the saturated absorption area away from gain region is coated with height
Anti- film.
Further, the mode locking semiconductor laser successively include bottom electrode, substrate, lower separation limiting layer, ducting layer,
Upper separation limiting layer, cap rock, Si02Current isolating layer and Top electrode.
The beneficial effects of the utility model：The utility model designs mode locked semiconductor on the basis of multimode interferometric structure and swashed
Light device, multimode interferometric structure plays the work of gain amplification using the wider gain area of multiple-mode interfence area waveguide as gain region
With so as to improve the luminous power of output pulse；Leptoprosopy accumulates area as uptake zone, the saturated absorption characteristic having using uptake zone
And its caused nonlinear refraction effect, light impulse length is effectively compressed, and single transverse mode output is can guarantee that, be conducive to light field again
Output coupling.The utility model proposes mode locking semiconductor laser can obtain high-power ultrashort pulse, and make simple, profit
It is integrated in optics.
Brief description of the drawings
Fig. 1 be the utility model proposes the mode locking semiconductor laser based on multimode interferometric structure structural representation；
Fig. 2 be the utility model proposes the mode locking semiconductor laser based on multimode interferometric structure the first ridge waveguide
Structural representation；
Fig. 3 be the utility model proposes the mode locking semiconductor laser chip schematic diagram based on multimode interferometric structure；
Fig. 4 be the utility model proposes the mode locking semiconductor laser based on multimode interferometric structure second of ridge waveguide
Structural representation.
Embodiment
For the purpose of this utility model, technical scheme and advantage is more clearly understood, below in conjunction with specific embodiment, and
Referring to the drawings, the utility model is further described.But those skilled in the art know, the utility model does not limit to
In accompanying drawing and following examples.The first and second grades statement described in text, merely to distinguishing each technical characteristic, has no essence
Implication.
The utility model proposes a kind of mode locking semiconductor laser based on multimode interferometric structure, as shown in figure 1, successively
By bottom electrode 108, the substrate 107 by material of GaAs, n-AlxGa1-xAs constitutes lower separation limiting layer 106, containing five layers of InGaAs
The ducting layer 105 of quantum dot and quantum dot layer interval GaAs isolation barriers layer, the material of upper separation limiting layer 104 are p-
AlxGa1-xAs, cap rock 103, Si02Current isolating layer 102, Top electrode 101 are constituted.
The waveguiding structure of the mode locking semiconductor laser can use slab waveguide structure, ridge waveguide structure, wedge-shaped waveguide
Structure etc., the refractive index of ducting layer 105 is more than the refractive index of upper separation limiting layer 104 and lower separation limiting layer 106.
Multimode interferometric structure is formed on the waveguiding structure, the multimode interferometric structure is by gain region, electricity isolated region, saturation
Uptake zone is constituted, and a part for a part for uptake zone, electricity isolated region and gain region can be constituted into multiple-mode interfence area, or
A part for gain region can also be constituted multiple-mode interfence area.
Below so that waveguiding structure uses ridge waveguide structure as an example, multimode interferometric structure is illustrated with reference to accompanying drawing.
Embodiment 1
Fig. 2 gives the first ridge waveguide structure schematic diagram of the mode locking semiconductor laser based on multimode interferometric structure,
Fig. 3 gives the mode locking semiconductor laser chip schematic diagram of the multimode interferometric structure including the present embodiment.In the ridge waveguide knot
Gain region 21, electricity isolated region 22 and saturated absorption area 23 are formed on the ridge of structure, electricity isolated region 22 is located at gain region 21 and saturation
Between uptake zone 23, gain region 21 and saturated absorption area 23 are electrically isolated.
Wherein, in order that gain is more than loss, the total length of gain region 21 is more than the total length in saturated absorption area 23, preferably
Ground, the length of gain region 21 is 3~10 times of the length in saturated absorption area 23.
Gain region 21 include the first strip 211 and from the first end face of the length direction of the first strip 211 along its
The second strip 212 being located on the axis that the axis of length direction extends, the second strip 212 is relative to the axis pair
Claim, the width of the second strip 212 is less than the width of the first strip 211, the first strip 211 is located at the second strip 212
The centre position of width；
Saturated absorption area 23 includes the first end face of the 3rd strip 231 and the length direction from the 3rd strip 231
The 4th strip 232 being located on the axis that axis along its length extends, the 4th strip 232 is relative to the axle
Line is symmetrical, and the width of the 4th strip 232 is less than the width of the 3rd strip 231；
The surface of the side of electricity isolated region 22 and the second end face of the remote first end face of the first strip 211 of gain region 21
Contact, the surface of relative opposite side and the second end face of the remote first end face of the 3rd strip 231 in saturated absorption area 23
Contact.Preferably, the size of length direction of the electricity isolated region 22 along gain region 21 is preferably 5~10um.
In the present embodiment, the 3rd length in the first strip 211 of gain region 21, electricity isolated region 22 and saturated absorption area 23
Bar shaped 231 together form multiple-mode interfence area 24, and the presence in multiple-mode interfence area makes the gain area of laser increase into multiple, more
Gain saturatiuon phenomenon is inhibited well, is played a part of gain amplification light pulse, is effectively improved the power of output light.
The length in multiple-mode interfence area 24 is that multimode waveguide exports the most short coupling length that section obtains single imaging.Such as multimode
The ridge waveguide width of waveguide section is set as width and the saturated absorption area 23 of the first strip 211 of 13um, i.e. gain region 21
The width of the 3rd strip 231 be 13um, the effective refractive index of waveguide section is 3.43, and effective refraction of limiting layer is separated up and down
Rate is 3.3, then the shortest length in multiple-mode interfence area is 460um.
Preferably, in order to ensure that single transverse mode is exported and beneficial to the coupling of light field, the width of single mode waveguide can neither be too wide
Can not be too narrow, the ridge waveguide width of single transverse mode is set here as 4um, i.e., the width of the second strip 212 of gain region 21 with
The width of 4th strip 232 in saturated absorption area 23 is 4um.
The end face of the one end of the second strip 212 away from the first strip 211 of gain region 21 goes out for plating anti-reflection film 25
Light end face, the reflectivity of anti-reflection film 25 is 3%；4th strip 232 in saturated absorption area 23 away from the 3rd strip 231 one
The end face plating high-reflecting film 26 at end, the reflectivity of high-reflecting film 26 is 97%.
The mode locking semiconductor laser operationally, forward current is applied on gain region 21, in saturated absorption area 23
Apply reverse biased.
Embodiment 2
The present embodiment and the difference of embodiment 1 are, in the present embodiment, and it is (right that saturated absorption area moves to long narrow bar shaped
The 4th strip 232 that should be in embodiment 1) on, the region conceded belongs to gain region.With reference to Fig. 4 to the present embodiment
Multimode interferometric structure is described.
Gain region 41, electricity isolated region 42 and saturated absorption area 43, electricity isolated region are formed on the ridge of the ridge waveguide structure
42 are located between gain region 41 and saturated absorption area 43, and gain region 41 and saturated absorption area 43 are electrically isolated.
Wherein, the total length of gain region 41 is more than the total length in saturated absorption area 43, it is preferable that the total length of gain region 41
It is 3~10 times of the total length in saturated absorption area 43.
Gain region 41 include the first strip 411, from the first end face of the length direction of the first strip 411 along its length
The second strip 412 being located on the axis that the axis in direction extends and from the length direction of the first strip 411
The 3rd strip 413 being located on the axis that the axis of second end face along its length extends, the He of the second strip 412
3rd strip 413 is both with respect to the axisymmetrical, and second end face is relative with first end face；Second strip 412 and the 3rd length
The width of bar shaped 413 is equal, respectively less than the width of the first strip 411, and the second strip 412 and the 3rd strip 413 are located at
The centre position of the width of first strip 411；
Saturated absorption area 43 includes the 4th strip 432, and the 4th strip 432 is located at the length direction of the first strip 411
Axis extended line on, the 4th strip 432 is symmetrical relative to the extended line of the axis, width of the 4th strip 432 etc.
In the width of the 3rd strip 413.
The surface of the side of electricity isolated region 42 and the extension end contact of the 3rd strip 413 of gain region 41, relative is another
The end contact on the surface of side and one end of the 4th strip 432 in saturated absorption area.Preferably, electricity isolated region 42 is along gain
The length direction in area 41 is sized to 5um~10um.
In the present embodiment, the first strip 411 of gain region 41 constitutes multiple-mode interfence area, and whole multiple-mode interfence area is equal
Belong to gain region 41, considerably increase the area in laser gain area, be conducive to the raising of laser output power.
The length in multiple-mode interfence area is that multimode waveguide exports the most short coupling length that section obtains single imaging.Such as multimode ripple
The ridge waveguide width for leading area is set as that the width of first strip 411 of 13um, i.e. gain region 41 is 13um, and waveguide section has
It is 3.43 to imitate refractive index, and the effective refractive index that limiting layer is separated up and down is 3.3, then the shortest length in multiple-mode interfence area is 460um.
Preferably, in order to ensure that single transverse mode is exported and beneficial to the coupling of light field, the width of single mode waveguide can neither be too wide
Can not be too narrow, the ridge waveguide width of single transverse mode is set here as 4um, i.e., the width of the second strip 412 of gain region 41 with
The width of the width of 3rd strip 413 and the 4th strip 432 in saturated absorption area 43 is 4um.
The end face of the one end of the second strip 412 away from the first strip 411 of gain region 41 is the light extraction of plating anti-reflection film
End face, the reflectivity of anti-reflection film is 3%；Threeth strip of 4th strip 432 away from gain region 41 in saturated absorption area 43
The end face plating high-reflecting film of 413 one end, the reflectivity of high-reflecting film is 97%.
The mode locking semiconductor laser operationally, forward current is applied on gain region 41, in saturated absorption area 43
Apply reverse biased.
Alternatively, the 3rd strip 413 of gain region 41 can also be saved in the present embodiment, i.e. the table of the side of electricity isolated region 42
Face is contacted with the second end face of the first strip 411 of gain region 41, surface and the saturated absorption area of relative opposite side
The end contact of one end of 43 the 4th strip 432.
More than, embodiment of the present utility model is illustrated.But, the utility model is not limited to above-mentioned implementation
Mode.It is all it is of the present utility model spirit and principle within, any modifications, equivalent substitutions and improvements done etc. should be included in
Within protection domain of the present utility model.
Claims (11)
1. a kind of mode locking semiconductor laser based on multimode interferometric structure, it is characterised in that the mode locking semiconductor laser is adopted
With slab waveguide structure, ridge waveguide structure or wedge-shaped waveguide structure, formed on the waveguiding structure gain region, electricity isolated region and
Saturated absorption area, the electricity isolated region is located between gain region and saturated absorption area, wherein, a part for the uptake zone, institute
The part for stating electricity isolated region and the gain region constitutes multimode interferometric structure, or the gain region a part constitute it is many
Mode interference structure.
2. mode locking semiconductor laser according to claim 1, it is characterised in that the total length of the gain region is more than full
With the total length of uptake zone.
3. mode locking semiconductor laser according to claim 1, it is characterised in that the length in the multiple-mode interfence area is many
Mould waveguide output section obtains the most short coupling length of single imaging.
4. the mode locking semiconductor laser according to any one of claim 1-3, it is characterised in that the gain region includes
What the first strip and axis from the first end face of the length direction of the first strip along its length extended is located at
The second strip on the axis, the second strip is less than the first strip relative to the axisymmetrical, the width of the second strip
The width of shape；
The saturated absorption area include the 3rd strip and from the first end face of the length direction of the 3rd strip along its length
The 4th strip being located on the axis that the axis in direction extends, the 4th strip is relative to the axisymmetrical；
The surface of the electricity isolated region side is contacted with the second end face of the remote first end face of the first strip of gain region, phase
To the surface of opposite side contacted with the second end face of the remote first end face of the 3rd strip in saturated absorption area；
The first strip, the electricity isolated region and the 3rd strip in the saturated absorption area of the gain region constitute institute together
State multiple-mode interfence area.
5. the mode locking semiconductor laser according to any one of claim 1-3, it is characterised in that the gain region includes
What the first strip, the axis from the first end face of the length direction of the first strip along its length extended is located at the axle
The second strip on line and the axis from the second end face of the length direction of the first strip along its length extend
Be located at the axis on the 3rd strip, the second strip and the 3rd strip are both with respect to the axisymmetrical, second end face
It is relative with first end face；The width of second strip and the 3rd strip is equal；
Saturated absorption area includes the 4th strip, and the 4th strip is located at the extended line of the axis of the first strip length direction
On, the 4th strip is symmetrical relative to the extended line of the axis, and the width of the 4th strip is equal to the width of the 3rd strip；
The surface of electricity isolated region side and the extension end contact of the 3rd strip of gain region, the surface of relative opposite side with
The end contact of one end of the 4th strip in saturated absorption area；
First strip of the gain region constitutes multiple-mode interfence area.
6. the mode locking semiconductor laser according to any one of claim 1-3, it is characterised in that the gain region includes
What the first strip, the axis from the first end face of the length direction of the first strip along its length extended is located at the axle
The second strip on line, the second strip is relative to the axisymmetrical；
Saturated absorption area includes the 4th strip, and the 4th strip is located at the extended line of the axis of the first strip length direction
On, and relative to the axisymmetrical, or positioned at the first strip length direction axis extended line either above or below,
But the scope of the second end face without departing from the remote first end face of the first strip of gain region；The width of 4th strip is equal to
The width of second strip；
The surface of electricity isolated region side is contacted with the second end face of the remote first end face of the first strip of gain region, relative
The end contact on the surface of opposite side and one end of the 4th strip in saturated absorption area；
First strip of the gain region constitutes multiple-mode interfence area.
7. mode locking semiconductor laser according to claim 4, it is characterised in that length side of the electricity isolated region along gain region
To size be 5um~10um.
8. mode locking semiconductor laser according to claim 1, it is characterised in that the light output end of gain region is coated with anti-reflection
Film；End face of the saturated absorption area away from gain region is coated with high-reflecting film.
9. mode locking semiconductor laser according to claim 1, it is characterised in that the mode locking semiconductor laser is successively
Including bottom electrode, substrate, lower separation limiting layer, ducting layer, upper separation limiting layer, cap rock, SiO2Current isolating layer and Top electrode.
10. mode locking semiconductor laser according to claim 5, it is characterised in that length of the electricity isolated region along gain region
The size in direction is 5um~10um.
11. mode locking semiconductor laser according to claim 6, it is characterised in that length of the electricity isolated region along gain region
The size in direction is 5um~10um.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106329310A (en) * | 2016-11-15 | 2017-01-11 | 中国科学院福建物质结构研究所 | Mode-locked semiconductor laser based on multimode interference structure |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106329310A (en) * | 2016-11-15 | 2017-01-11 | 中国科学院福建物质结构研究所 | Mode-locked semiconductor laser based on multimode interference structure |
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