Semiconductor laser element

Abstract

The semiconductor laser element sequentially comprises a substrate, a lower limiting layer, a lower waveguide layer, an active layer, an upper waveguide layer and an upper limiting layer from bottom to top, and a chiral continuous domain bound state layer is arranged between the upper waveguide layer and the upper limiting layer; the filipp ionization degree distribution of the chiral continuous domain bound state layer has curve distribution of a function y = ax < 3 > + bx < 2 > + cx + d (a > 0, = 4 (b2-3a) < 0); the Philips ionization degree of the upper waveguide layer is greater than or equal to the Philips ionization degree of the chiral continuous domain bound state layer and is greater than or equal to the Philips ionization degree of the upper limiting layer; and the conduction band effective state density distribution of the chiral continuous domain bound state layer has fourth quadrant curve distribution of a function y = A + B * x / lnx. According to the invention, a three-dimensional chiral structure is formed by using out-of-plane mirror symmetry and in-plane mirror asymmetry, so that the chiral interaction between laser and circularly polarized light in a specific spin direction is enhanced, electron and photon dual three-dimensional strong limitation is enhanced, near-field coupled light beam deflection and focusing are realized, and laser coherence, far-field FFP quality and light beam quality factors are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor optoelectronic devices, and in particular to a semiconductor laser element. Background Art

[0002] Lasers are widely used in laser display, laser TV, laser projector, communication, medical treatment, weapons, guidance, ranging, spectral analysis, cutting, precision welding, high-density optical storage and other fields. There are many types of lasers, and the classification methods are also diverse, mainly including solid, gas, liquid, semiconductor and dye types of lasers; compared with other types of lasers, all-solid-state semiconductor lasers have the advantages of small size, high efficiency, light weight, good stability, long life, simple and compact structure, and miniaturization.

[0003] There are significant differences between lasers and nitride semiconductor light-emitting diodes.

[0004] 1) Laser is generated by stimulated radiation of carriers, the spectrum half-width is small, the brightness is very high, and the output power of a single laser can be in the W level, while nitride semiconductor light-emitting diodes are spontaneously radiated, and the output power of a single light-emitting diode is in the mW level;

[0005] 2) The current density of the laser is up to KA / cm 2 , which is more than 2 orders of magnitude higher than that of nitride light-emitting diodes, resulting in stronger electron leakage, more serious Auger recombination, stronger polarization effect, more serious electron-hole mismatch, and more serious efficiency attenuation Droop effect;

[0006] 3) The spontaneous transition radiation of the light-emitting diode is incoherent light that transitions from a high energy level to a low energy level without any external influence, while the laser is stimulated transition radiation, and the energy of the induced photon should be equal to the difference in the energy level of the electron transition, producing the same coherent light as the photon and the induced photon;

[0007] 4) Different principles: When an external voltage is applied to a light-emitting diode, electron holes jump to a quantum well or a pn junction to generate radiative recombination light, while a laser can only emit when the lasing conditions are met. The carrier distribution in the active region must be reversed, and the stimulated radiation light oscillates back and forth in the resonant cavity. The propagation in the gain medium amplifies the light, and the threshold condition is met so that the gain is greater than the loss, and finally the laser is output.

[0008] Nitride semiconductor lasers have the following problems:

[0009] 1) The fewer the number of laser modes, the more favorable it is to stimulated radiation, the more favorable it is to improve the degeneracy of photons, and the more favorable it is to make stimulated radiation exceed spontaneous radiation; the laser light wave can be divided into transverse mode and longitudinal and transverse mode; the transverse mode intensity distribution in the cross section perpendicular to the optical axis is determined by the waveguide structure of the semiconductor laser. If the transverse mode is complex and unstable, the coherence of the output light is poor; the longitudinal mode is a standing wave distribution in the propagation direction of the resonant cavity. If many longitudinal modes are emitted at the same time or there are inter-mode changes, high temporal coherence cannot be obtained, and the far-field image FFP quality is poor.

[0010] 2) The light field is dissipated, and the light field mode leaks into the substrate to form standing waves, which leads to low substrate mode suppression efficiency and poor far-field image FFP quality. Summary of the invention

[0011] The present invention proposes a semiconductor laser element, wherein the chiral continuous domain bound state layer utilizes out-of-plane mirror symmetry and in-plane mirror asymmetry to form a three-dimensional chiral structure, thereby enhancing the chiral interaction between laser and circularly polarized light with a specific spin direction, and enhancing the dual three-dimensional strong confinement of electrons and photons, thereby realizing near-field coupled beam deflection and focusing, improving laser coherence, far-field FFP quality and beam quality factor, and reducing the focused spot size.

[0012] The present invention provides a semiconductor laser element, which comprises, from bottom to top, a substrate, a lower confinement layer, a lower waveguide layer, an active layer, an upper waveguide layer, and an upper confinement layer, wherein a chiral continuous domain bound state layer is provided between the upper waveguide layer and the upper confinement layer; the Philips ionization degree distribution of the chiral continuous domain bound state layer has a function y=ax 3 +bx 2 +cx+d(a>0,△=4(b 2 -3ac)<0) curve distribution; the Philips ionization degree of the upper waveguide layer ≥ the Philips ionization degree of the chiral continuum bound state layer ≥ the Philips ionization degree of the upper confinement layer; the conduction band effective state density distribution of the chiral continuum bound state layer has a fourth quadrant curve distribution of the function y=A+B*x / lnx, wherein A and B are arbitrary values; the Philips ionization degree of the upper confinement layer ≥ the Philips ionization degree of the chiral continuum bound state layer ≥ the Philips ionization degree of the upper waveguide layer.

[0013] Preferably, the refractive index coefficient distribution of the chiral continuum bound state layer has a function y=ex 3 +fx 2 +gx+h(e>0,△=4(f 2 -3eg)<0 curve distribution; the refractive index coefficient of the upper waveguide layer ≥ the refractive index coefficient of the chiral continuous domain bound state layer ≥ the refractive index coefficient of the upper confinement layer.

[0014] Preferably, the dielectric constant distribution of the chiral continuum bound state layer has a function y=C+D*arthx curve distribution, wherein C and D are arbitrary values; the dielectric constant of the upper waveguide layer ≥ the dielectric constant of the chiral continuum bound state layer ≥ the dielectric constant of the upper confinement layer.

[0015] Preferably, the Philips ionization degree distribution, conduction band effective state density distribution, refractive index coefficient distribution, and dielectric constant distribution of the chiral continuous domain bound state layer have the following relationship: A≥C≥h≥d.

[0016] Preferably, the In / H element ratio distribution of the chiral continuous domain bound state layer has a curve distribution of function y=E+F*tanx; the In / C element ratio distribution of the chiral continuous domain bound state layer has a curve distribution of function y=G+H*arthx; the In / O element ratio distribution of the chiral continuous domain bound state layer has a curve distribution of function y=J+K*arcsinx; wherein E, G, and J are arbitrary values, and J≥G≥E.

[0017] Preferably, the chiral continuous domain bound state layer is any one or any combination of GaN, InGaN, InN, AlInN, AlGaN, AlInGaN, AlN, GaAs, GaP, InP, AlGaAs, AlInGaAs, AlGaInP, InGaAs, InGaAsN, AlInAs, AlInP, AlGaP, InGaP, GaSb, InSb, InAs, InAsSb, AlGaSb, AlSb, InGaSb, AlGaAsSb, InGaAsSb, SiC, Ga2O3, and BN.

[0018] Preferably, the active layer is a periodic structure composed of a well layer and a barrier layer, the number of periods is 3≥m≥1, and the well layer is any one of GaN, InGaN, InN, AlInN, AlGaN, AlInGaN, AlN, GaAs, GaP, InP, AlGaAs, AlInGaAs, AlGaInP, InGaAs, InGaAsN, AlInAs, AlInP, AlGaP, InGaP, GaSb, InSb, InAs, InAsSb, AlGaSb, AlSb, InGaSb, AlGaAsSb, InGaAsSb, SiC, Ga2O3, BN or Any combination, with a thickness of 10 to 100 angstroms, and the barrier layer is any one or any combination of GaN, InGaN, InN, AlInN, AlGaN, AlInGaN, AlN, GaAs, GaP, InP, AlGaAs, AlInGaAs, AlGaInP, InGaAs, InGaAsN, AlInAs, AlInP, AlGaP, InGaP, GaSb, InSb, InAs, InAsSb, AlGaSb, AlSb, InGaSb, AlGaAsSb, InGaAsSb, SiC, Ga2O3, and BN, with a thickness of 10 to 200 angstroms.

[0019] Preferably, the lower limiting layer, the lower waveguide layer, the upper waveguide layer, and the upper limiting layer are any one or any combination of GaN, InGaN, InN, AlInN, AlGaN, AlInGaN, AlN, GaAs, GaP, InP, AlGaAs, AlInGaAs, AlGaInP, InGaAs, InGaAsN, AlInAs, AlInP, AlGaP, InGaP, GaSb, InSb, InAs, InAsSb, AlGaSb, AlSb, InGaSb, AlGaAsSb, InGaAsSb, SiC, Ga2O3, and BN.

[0020] Preferably, the substrate comprises sapphire, silicon, Ge, SiC, AlN, GaN, GaAs, InP, InAs, GaSb, sapphire / SiO2 composite substrate, sapphire / AlN composite substrate, sapphire / SiN x , Sapphire / SiO2 / SiN x Any one of a composite substrate, a magnesium aluminum spinel MgAl2O4, MgO, ZnO, ZrB2, LiAlO2 and LiGaO2 composite substrate.

[0021] Compared with the prior art, the semiconductor laser element provided by the embodiment of the present invention has the following beneficial effects:

[0022] The chiral continuous domain bound state layer utilizes out-of-plane mirror symmetry and in-plane mirror asymmetry to form a three-dimensional chiral structure, enhances the chiral interaction between laser and circularly polarized light with a specific spin direction, and enhances the dual three-dimensional strong confinement of electrons and photons, realizes near-field coupled beam deflection and focusing, improves laser coherence, far-field FFP quality and beam quality factor, and reduces the focused spot size; and generates topological optical force to manipulate the optical force distribution of the conduction band and valence band of the active layer, generates a skyrmion Hall effect, induces modulation inversion symmetry breaking and quasi-Fermi level pinning effect, solves the problems of capacitance sinking and ideal factor jump, and reduces the temperature quenching ratio.

[0023] At the same time, the chiral continuous domain bound state layer breaks the Z-axis symmetry and angular symmetry, changing the far-field polarization state of the laser from a linear polarization vortex to an elliptically polarized vortex, so that the intrinsic electric field is bound around the waveguide layer and quantum well of the laser, limiting the propagation of light in the upper and lower waveguide layers, improving the laser's light field localization capability and quality factor, and enhancing the nonlinear harmonics of the interaction between light and matter, reducing mechanical losses and light field dissipation, and suppressing the leakage of light field modes to the substrate, further improving the far-field image FFP quality and limitation factor, and improving the laser spectrum purity and beam quality factor. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 is a schematic structural diagram of a semiconductor laser element according to an embodiment of the present invention;

[0025] Reference numerals: 100: substrate; 101: lower confinement layer; 102: lower waveguide layer; 103: active layer; 104: upper waveguide layer, 105: upper confinement layer, 106: chiral continuous domain bound state layer. DETAILED DESCRIPTION

[0026] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] In order to solve the above problems, a semiconductor laser element provided in an embodiment of the present application will be introduced and explained in detail through the following specific embodiments.

[0028] Reference Figure 1The present invention provides a semiconductor laser element, which comprises, from bottom to top, a substrate 100, a lower confinement layer 101, a lower waveguide layer 102, an active layer 103, an upper waveguide layer 104, and an upper confinement layer 105, wherein a chiral continuous domain bound state layer 106 is provided between the upper waveguide layer 104 and the upper confinement layer 105; the Philips ionization degree distribution of the chiral continuous domain bound state layer 106 has a function y=ax 3 +bx 2 +cx+d(a>0,△=4(b 2 -3ac)<0) curve distribution; the Philips ionization degree of the upper waveguide layer 104 ≥ the Philips ionization degree of the chiral continuum bound state layer 106 ≥ the Philips ionization degree of the upper confinement layer 105; the conduction band effective state density distribution of the chiral continuum bound state layer 106 has a fourth quadrant curve distribution of the function y=A+B*x / lnx, wherein A and B are arbitrary values; the Philips ionization degree of the upper confinement layer 105 ≥ the Philips ionization degree of the chiral continuum bound state layer 106 ≥ the Philips ionization degree of the upper waveguide layer 104.

[0029] The refractive index coefficient distribution of the chiral continuum bound state layer 106 has a function y=ex 3 +fx 2 +gx+h(e>0,△=4(f 2 -3eg)<0 curve distribution; the refractive index coefficient of the upper waveguide layer 104 ≥ the refractive index coefficient of the chiral continuous domain bound state layer 106 ≥ the refractive index coefficient of the upper confinement layer 105.

[0030] The dielectric constant distribution of the chiral continuum bound state layer 106 has a function y=C+D*arthx curve distribution, where C and D are arbitrary values; the dielectric constant of the upper waveguide layer 104 ≥ the dielectric constant of the chiral continuum bound state layer 106 ≥ the dielectric constant of the upper confinement layer 105 .

[0031] The Philips ionization degree distribution, conduction band effective state density distribution, refractive index coefficient distribution, and dielectric constant distribution of the chiral continuous domain bound state layer 106 have the following relationship: A≥C≥h≥d.

[0032] The In / H element ratio distribution of the chiral continuous domain bound state layer 106 has a curve distribution of function y=E+F*tanx; the In / C element ratio distribution of the chiral continuous domain bound state layer 106 has a curve distribution of function y=G+H*arthx; the In / O element ratio distribution of the chiral continuous domain bound state layer 106 has a curve distribution of function y=J+K*arcsinx; wherein E, G, and J are arbitrary values, and J≥G≥E.

[0033] The chiral continuous domain bound state layer 106 is any one or any combination of GaN, InGaN, InN, AlInN, AlGaN, AlInGaN, AlN, GaAs, GaP, InP, AlGaAs, AlInGaAs, AlGaInP, InGaAs, InGaAsN, AlInAs, AlInP, AlGaP, InGaP, GaSb, InSb, InAs, InAsSb, AlGaSb, AlSb, InGaSb, AlGaAsSb, InGaAsSb, SiC, Ga2O3, and BN.

[0034] The chiral continuum bound state layer 106 forms a three-dimensional chiral structure by using out-of-plane mirror symmetry and in-plane mirror asymmetry, enhancing the chiral interaction between laser and circularly polarized light of a specific spin direction, and enhancing the dual three-dimensional strong confinement of electrons and photons, realizing near-field coupled beam deflection and focusing, improving laser coherence, far-field FFP quality and beam quality factor, and reducing the focused spot size; and generating topological optical force to manipulate the optical force distribution of the conduction band and valence band of the active layer, generating skyrmion Hall effect, inducing modulation inversion symmetry breaking and quasi-Fermi level pinning effect, solving the problem of capacitance sinking and ideal factor jump, and reducing the temperature quenching ratio. As shown in the following table:

[0035] Blue Laser Project Conventional laser Laser of the present invention Range of change <![CDATA[Beam quality factor M 2 > 3.7 1.36 172％ Limiting Factor 1.40％ 2.97％ 112％ <![CDATA[Internal optical loss (cm -1 )]]> 17.2 11.3 -34％ Temperature quenching ratio (PPM) 127 14 -89％ Focused spot size (nm) >250 <20

[0036] In the present invention, the active layer 103 is a periodic structure composed of a well layer and a barrier layer, the number of periods is 3≥m≥1, and the well layer is any one of GaN, InGaN, InN, AlInN, AlGaN, AlInGaN, AlN, GaAs, GaP, InP, AlGaAs, AlInGaAs, AlGaInP, InGaAs, InGaAsN, AlInAs, AlInP, AlGaP, InGaP, GaSb, InSb, InAs, InAsSb, AlGaSb, AlSb, InGaSb, AlGaAsSb, InGaAsSb, SiC, Ga2O3, and BN. any one or any combination thereof, with a thickness of 10 to 100 angstroms, and the barrier layer is any one or any combination of GaN, InGaN, InN, AlInN, AlGaN, AlInGaN, AlN, GaAs, GaP, InP, AlGaAs, AlInGaAs, AlGaInP, InGaAs, InGaAsN, AlInAs, AlInP, AlGaP, InGaP, GaSb, InSb, InAs, InAsSb, AlGaSb, AlSb, InGaSb, AlGaAsSb, InGaAsSb, SiC, Ga2O3, and BN, with a thickness of 10 to 200 angstroms.

[0037] In the present invention, the lower confinement layer 101, the lower waveguide layer 102, the upper waveguide layer 104, and the upper confinement layer 105 are any one or any combination of GaN, InGaN, InN, AlInN, AlGaN, AlInGaN, AlN, GaAs, GaP, InP, AlGaAs, AlInGaAs, AlGaInP, InGaAs, InGaAsN, AlInAs, AlInP, AlGaP, InGaP, GaSb, InSb, InAs, InAsSb, AlGaSb, AlSb, InGaSb, AlGaAsSb, InGaAsSb, SiC, Ga2O3, and BN.

[0038] In the present invention, the substrate 100 includes sapphire, silicon, Ge, SiC, AlN, GaN, GaAs, InP, InAs, GaSb, sapphire / SiO2 composite substrate, sapphire / AlN composite substrate, sapphire / SiN x , Sapphire / SiO2 / SiN x Any one of a composite substrate, a magnesium aluminum spinel MgAl2O4, MgO, ZnO, ZrB2, LiAlO2 and LiGaO2 composite substrate.

[0039] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A semiconductor laser element, comprising, from bottom to top, a substrate (100), a lower confinement layer (101), a lower waveguide layer (102), an active layer (103), an upper waveguide layer (104), and an upper confinement layer (105), It is characterized in that A chiral continuous domain bound state layer (106) is provided between the upper waveguide layer (104) and the upper confinement layer (105); the Philips ionization degree distribution of the chiral continuous domain bound state layer (106) has a function y=ax 3 +bx 2 +cx+d(a>0,△=4(b 2 -3ac)<0) curve distribution; the Philips ionization degree of the upper waveguide layer (104) ≥ the Philips ionization degree of the chiral continuous domain bound state layer (106) ≥ the Philips ionization degree of the upper confinement layer (105); the conduction band effective state density distribution of the chiral continuous domain bound state layer (106) has a fourth quadrant curve distribution of the function y=A+B*x / lnx, wherein A and B are arbitrary values; the Philips ionization degree of the upper confinement layer (105) ≥ the Philips ionization degree of the chiral continuous domain bound state layer (106) ≥ the Philips ionization degree of the upper waveguide layer (104).

2. A semiconductor laser element according to claim 1, It is characterized in that The refractive index coefficient distribution of the chiral continuous domain bound state layer (106) has a function y=ex 3 +fx 2 +gx+h(e>0,△=4(f 2 -3eg)<0 curve distribution; the refractive index coefficient of the upper waveguide layer (104) ≥ the refractive index coefficient of the chiral continuous domain bound state layer (106) ≥ the refractive index coefficient of the upper confinement layer (105).

3. The semiconductor laser element according to claim 1, It is characterized in that The dielectric constant distribution of the chiral continuous domain bound state layer (106) has a function y=C+D*arthx curve distribution, wherein C and D are arbitrary values; the dielectric constant of the upper waveguide layer (104) is ≥ the dielectric constant of the chiral continuous domain bound state layer (106) ≥ the dielectric constant of the upper confinement layer (105).

4. A semiconductor laser element according to claim 3, It is characterized in that The Philips ionization degree distribution, conduction band effective state density distribution, refractive index coefficient distribution and dielectric constant distribution of the chiral continuous domain bound state layer (106) have the following relationship: A≥C≥h≥d.

5. The semiconductor laser element according to claim 1, It is characterized in that The In / H element ratio distribution of the chiral continuous domain bound state layer (106) has a function y=E+F*tanx curve distribution; the In / C element ratio distribution of the chiral continuous domain bound state layer (106) has a function y=G+H*arthx curve distribution; the In / O element ratio distribution of the chiral continuous domain bound state layer (106) has a function y=J+K*arcsinx curve distribution; wherein E, G, and J are arbitrary values, and J≥G≥E.

6. A semiconductor laser element according to claim 1, It is characterized in that The chiral continuous domain bound state layer (106) is GaN, InGaN, InN, AlInN, AlGaN, AlInGaN, AlN, GaAs, GaP, InP, AlGaAs, AlInGaAs, AlGaInP, InGaAs , InGaAsN, AlInAs, AlInP, AlGaP, InGaP, GaSb, InSb, InAs, InAsSb, AlGaSb, AlSb, InGaSb, AlGaAsSb, InGaAsSb, SiC, Ga 2 O 3 , BN or any combination thereof.

7. A semiconductor laser element according to claim 1, It is characterized in that The active layer (103) is a periodic structure composed of a well layer and a barrier layer, the number of periods is 3≥m≥1, and the well layer is GaN, InGaN, InN, AlInN, AlGaN, AlInGaN, AlN, GaAs, GaP, InP, AlGaAs, AlInGaAs, AlGaInP, InGaAs, InGaAsN, AlInAs, AlInP, AlGaP, InGaP, GaSb, InSb, InAs, InAsSb, AlGaSb, AlSb, InGaSb, AlGaAsSb, InGaAsSb, SiC, Ga 2 O 3 , BN, any one or any combination thereof, with a thickness of 10 to 100 angstroms, and a barrier layer of GaN, InGaN, InN, AlInN, AlGaN, AlInGaN, AlN, GaAs, GaP, InP, AlGaAs, AlInGaAs, AlGaInP, InGaAs, InGaAsN, AlInAs, AlInP, AlGaP, InGaP, GaSb, InSb, InAs, InAsSb, AlGaSb, AlSb, InGaSb, AlGaAsSb, InGaAsSb, SiC, Ga 2 O 3 , BN, any one or any combination thereof, with a thickness of 10 to 200 angstroms.

8. The semiconductor laser element according to claim 1, It is characterized in that The lower confinement layer (101), the lower waveguide layer (102), the upper waveguide layer (104), and the upper confinement layer (105) are GaN, InGaN, InN, AlInN, AlGaN, AlInGaN, AlN, GaAs, GaP, InP, AlGaAs, AlInGaAs, AlGaInP, InGaAs, InGaAsN, AlInAs, AlInP, AlGaP, InGaP, GaSb, InSb, InAs, InAsSb, AlGaSb, AlSb, InGaSb, AlGaAsSb, InGaAsSb, SiC, Ga 2 O 3 , any one or any combination of BN.

9. The semiconductor laser element according to claim 1, It is characterized in that The substrate (100) includes sapphire, silicon, Ge, SiC, AlN, GaN, GaAs, InP, InAs, GaSb, sapphire / SiO 2 Composite substrate, sapphire / AlN composite substrate, sapphire / SiN x , Sapphire / SiO 2 / SiN x Composite substrate, magnesium aluminum spinel MgAl 2 O 4 、MgO、ZnO、ZrB 2 、LiAlO 2 and LiGaO 2 Any type of composite substrate.

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