CN113381279B - Narrow-linewidth ultraviolet Raman laser - Google Patents
Narrow-linewidth ultraviolet Raman laser Download PDFInfo
- Publication number
- CN113381279B CN113381279B CN202110625904.3A CN202110625904A CN113381279B CN 113381279 B CN113381279 B CN 113381279B CN 202110625904 A CN202110625904 A CN 202110625904A CN 113381279 B CN113381279 B CN 113381279B
- Authority
- CN
- China
- Prior art keywords
- mirror
- light
- frequency doubling
- crystal
- plated
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
- H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
- H01S3/30—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range using scattering effects, e.g. stimulated Brillouin or Raman effects
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
- H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
- H01S3/05—Construction or shape of optical resonators; Accommodation of active medium therein; Shape of active medium
- H01S3/08—Construction or shape of optical resonators or components thereof
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
- H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
- H01S3/05—Construction or shape of optical resonators; Accommodation of active medium therein; Shape of active medium
- H01S3/08—Construction or shape of optical resonators or components thereof
- H01S3/08059—Constructional details of the reflector, e.g. shape
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
- H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
- H01S3/10—Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating
- H01S3/106—Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating by controlling devices placed within the cavity
- H01S3/108—Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating by controlling devices placed within the cavity using non-linear optical devices, e.g. exhibiting Brillouin or Raman scattering
- H01S3/1086—Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating by controlling devices placed within the cavity using non-linear optical devices, e.g. exhibiting Brillouin or Raman scattering using scattering effects, e.g. Raman or Brillouin effect
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
- H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
- H01S3/10—Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating
- H01S3/106—Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating by controlling devices placed within the cavity
- H01S3/108—Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating by controlling devices placed within the cavity using non-linear optical devices, e.g. exhibiting Brillouin or Raman scattering
- H01S3/109—Frequency multiplication, e.g. harmonic generation
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
- Y02A90/00—Technologies having an indirect contribution to adaptation to climate change
- Y02A90/10—Information and communication technologies [ICT] supporting adaptation to climate change, e.g. for weather forecasting or climate simulation
Landscapes
- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Engineering & Computer Science (AREA)
- Plasma & Fusion (AREA)
- Optics & Photonics (AREA)
- Nonlinear Science (AREA)
- Optical Modulation, Optical Deflection, Nonlinear Optics, Optical Demodulation, Optical Logic Elements (AREA)
Abstract
The invention discloses a narrow linewidth ultraviolet Raman laser, which comprises: the laser emitting part is used for emitting a first optical signal with tunable first preset power and first preset wavelength, and the first optical signal penetrates through the input mirror to enter the diamond crystal; the diamond crystal is used for converting the first optical signal into a Stokes optical signal by utilizing an SRS effect and entering the first frequency doubling crystal through the first reflector; the first frequency doubling crystal is used for converting the Stokes optical signal into a frequency doubling optical signal by utilizing a second-order nonlinear effect and outputting the frequency doubling optical signal through the output mirror; and the lock cavity frequency doubling part is used for carrying out secondary frequency doubling on the frequency doubling optical signal so as to generate and output stable narrow-linewidth ultraviolet laser. The Stokes light oscillates in the Raman oscillator composed of the input mirror, the second reflecting mirror and the output mirror, and the residual pumping light penetrating through the second reflecting mirror enters the diamond crystal again and is focused in the diamond crystal after passing through the third reflecting mirror, so that the utilization rate of the pumping light is improved.
Description
Technical Field
The invention relates to the field of Raman lasers, in particular to a narrow-linewidth ultraviolet Raman laser.
Background
The laser in the ultraviolet band has the characteristics of short wavelength, better focusing effect, high single photon energy and the like, so that the ultraviolet laser is widely applied to the fields of industrial processing, scientific research, military, medical treatment and the like. The laser with narrow line width has wide application prospect in the fields of laser radar, metrology, quantum physics and the like. The current method for obtaining narrow-linewidth ultraviolet band is to utilize frequency multiplication effect first, then utilize sum frequency effect, and finally obtain ultraviolet laser. However, this method of obtaining the ultraviolet laser requires two frequency conversions, which may result in low conversion efficiency and reduced beam quality. With the development of nonlinear technology, the Stimulated Raman Scattering (SRS) effect caused by molecular vibration of raman medium becomes an important means for realizing large laser frequency conversion. Raman lasers based on SRS have many advantages: laser output of rare earth ion emission cross section vacancy wavelength can be realized through Raman frequency shift, and people can realize output from deep ultraviolet to medium wave infrared by utilizing Raman conversion at present; the Raman frequency shift is only related to the medium lattice vibration and is unrelated to the frequency of the pump light, so that the Raman light with the same frequency tuning range can be obtained by tuning the frequency of the pump light; the Raman gain is in direct proportion to the pump light intensity, the saturation effect and the spatial hole burning effect do not exist, the output power of the Raman laser directly depends on the pump light power, and the energy conversion and the output of narrow line width close to the quantum efficiency limit can be realized.
At present, researchers have realized the output of the raman laser through a straight cavity and a ring cavity, however, in the high-power operation, the raman medium in the resonant cavity absorbs the residual pump light to generate the thermal effect, and the stability of the resonant cavity is greatly interfered. Meanwhile, the returning light of the Stokes cannot be separated from the pumping light, so that the returning light directly returns to the position of the pumping light source, the returning light is easily damaged, and the stability is easily affected, so that the improvement and the application of the power of the Raman laser are limited to a great extent. In addition, currently, for space environment detection, there is an important demand for an ultraviolet raman laser with a narrow line width and adjustable wavelength range, but it is difficult to simultaneously realize narrow line width and adjustable ultraviolet wavelength based on nonlinear frequency conversion of a conventional solid laser.
Disclosure of Invention
The invention provides a narrow linewidth ultraviolet Raman laser, which realizes the adjustability of narrow linewidth and ultraviolet wavelength, and is described in detail as follows:
the invention provides a narrow linewidth ultraviolet Raman laser, which comprises: the device comprises a pumping source, an optical isolator, a half-wave plate, a focusing lens, an input mirror, a diamond crystal, a first reflector, a first frequency doubling crystal, an output mirror, a second reflector, a shaping lens, a cavity-locking frequency multiplier and a dichroic mirror, wherein the input mirror, the first reflector and the output mirror form a V-shaped cavity structure; the diamond crystal is positioned between the input mirror and the first reflecting mirror, and the first frequency doubling crystal is positioned between the first reflecting mirror and the output mirror;
the lock cavity frequency multiplier consists of a lock cavity input mirror, a first lock cavity reflector, a second frequency doubling crystal and a lock cavity output mirror;
the pump source emits a first optical signal having a tunable first predetermined power and a first predetermined wavelength, i.e. having a frequency ωPThe pumping light passes through the half wave plate, the optical isolator, the focusing lens and the input mirror and is focused at the center of the diamond crystal, the pumping light excites the ground state atoms of the diamond crystal to the virtual Raman upper energy level to generate pumping light with a frequency of omegaSAnd a frequency of omegaRAnd optical phonon of (1), and satisfies ωP＝ωS+ωR；
The diamond crystal is used for converting the first optical signal into a Stokes optical signal by utilizing an SRS effect; the Stokes optical signal oscillates in a Raman oscillator consisting of an input mirror, a first reflecting mirror and an output mirror, and the residual pumping light penetrating through the first reflecting mirror enters and focuses in the diamond crystal again after being reflected by a second reflecting mirror so as to improve the utilization rate of the pumping light;
the Stokes optical signal enters the first frequency doubling crystal through the first reflector, and after the Stokes optical signal excites the first-stage frequency doubling light in the first frequency doubling crystal, the first-stage frequency doubling light is output through the output mirror; the first-stage frequency doubling light enters the lock cavity frequency multiplier after passing through the shaping lens, is focused at the center of the second-stage frequency doubling crystal, is excited to emit second-stage frequency doubling light, and is output through the lock cavity output mirror.
The invention provides a narrow-linewidth ultraviolet Raman laser, which has the following beneficial effects:
1. the invention provides a laser resonant cavity with a V-shaped cavity structure, through the design of a reflector in the cavity, the separation of residual pump light and Stokes light is realized at the reflector, the coating requirement of an output coupling mirror is reduced, and meanwhile, the requirement on an optical isolator is reduced and the stability of the resonant cavity is improved; the laser adopting the V-shaped cavity structure design enables a plurality of light waists to be formed in the cavity, the Raman crystal and other nonlinear crystals are placed at the light waists, the threshold value of the nonlinear process is reduced, the Raman conversion efficiency and the nonlinear conversion efficiency are improved, and pure laser output with special wavelengths (such as 589nm and 620 nm) is generated while Raman laser resonates.
2. The invention provides a cavity-locked frequency multiplier with an annular cavity structure, which reduces the loss in the transmission process, can effectively increase the length of a cavity-locked frequency multiplication cavity and is beneficial to reducing the line width of an output optical signal. The invention realizes the output of the ultraviolet wavelength with narrow line width of 310nm based on the structure, and is detailed in example 1 or example 2.
Drawings
FIG. 1 is a schematic structural diagram of a single-pass pumping narrow linewidth UV Raman laser;
FIG. 2 is a schematic diagram of a two-way pumping narrow linewidth ultraviolet Raman laser structure;
fig. 3 is a schematic structural diagram of a lock cavity frequency multiplier.
In the drawings, the components represented by the respective reference numerals are listed below:
1: a pump source; 2: a half wave plate;
3: a focusing lens; 4: an input mirror;
5: diamond crystals; 6: a first reflector;
7: a first frequency doubling crystal; 8: an output mirror;
9: a shaping lens; 10: a lock cavity frequency multiplier;
11: a dichroic mirror; 12: an optical isolator;
13: a first reflector; 14: a second mirror.
Wherein:
10-1: a lock cavity input mirror; 10-2: a first lock cavity mirror;
10-3: a second lock cavity mirror; 10-4: a second frequency doubling crystal;
10-5: a lock cavity output mirror;
l1: the distance between the input mirror and the left end face of the diamond crystal;
l2: the distance between the right end face of the diamond crystal and the first reflector;
l3: the distance between the first reflector and the right end face of the first frequency doubling crystal;
l4: the distance between the left end surface of the first frequency doubling crystal and the output mirror;
l5: the distance between the first reflector and the second reflector.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, embodiments of the present invention are described in further detail below.
The Raman laser with the structure different from the traditional standing wave cavity adopts a V-shaped cavity structure, the separation of the pumping light and the Stokes light can be easily realized at the turning mirror of the cavity, and the interference of the residual pumping light on the stability of the resonant cavity can be effectively reduced. And adopt V die cavity structure, can make the intracavity have two light waists, and then gain medium, nonlinear crystal can independently lay respectively in the light waist department of position diverse to realize the mutual matching of each parameter, increase the light conversion efficiency, design into V type folding chamber with Raman laser's structure, compacter like this, more be favorable to the engineering. Meanwhile, the Raman crystal with good thermal performance can bear higher pumping power, thereby being beneficial to obtaining higher-power laser output.
The Raman laser which adopts a novel Raman oscillator structure and a high-thermal-conductivity working substance to realize free space operation is a favorable way for obtaining high-power special wavelength output, and has important significance for the development of the fields of biological medicine, astronomical imaging, space detection and the like.
Example 1
Referring to fig. 1 and 3, a narrow linewidth ultraviolet raman laser comprises: the device comprises a pumping source 1, a half wave plate 2, a focusing lens 3, an input mirror 4, a diamond crystal 5, a first reflecting mirror 6, a first frequency doubling crystal 7, an output mirror 8, a shaping lens 9, a cavity-locked frequency multiplier 10 and a dichroic mirror 11.
Wherein, the output frequency of the pump source 1 is omegaPThe wavelength of the linear polarization state pump light is adjustable within 1.02-1.08 mu m, and the spectral line width<0.1 nm; the half wave plate 2 is used for adjusting the polarization state of the pump light; the focusing lens 3 is a broadband dielectric film plated with an anti-reflection film for the wavelength of the pump light of 1.02-1.08 mu m; the input mirror 4 is a plano-concave mirror with a curvature radius of 50mm, two surfaces of the plano-concave mirror are plated with broadband dielectric films for increasing the transmission of the pump light, and the concave surface of the plano-concave mirror is plated with reflectivity of 1.18-1.26 mu m waveband for Stokes light>99.8% of broadband dielectric film; diamond crystal 5 is rim<110>Shaft-cut synthetic diamond crystals of size 7X 4X 1.2mm3Two end faces are plated with wave band transmittances of 1.02-1.08 mu m for pump light and 1.18-1.26 mu m for Stokes light>99.5% of broadband dielectric film; the first reflector 6 is a plano-concave mirror with curvature radius of 100mm, and the concave surface is plated with light transmittance to the pump>98% broadband dielectric film and Stokes light reflectivity>99.8% of broadband dielectric film, the included angle between the first reflector 6 and the incident pump light is 2 degrees; the first frequency doubling crystal 7 is a temperature phase matching LBO crystal with a cutting angle theta of 90 DEG and phi of 0 DEG, both ends are coated with broadband dielectric films for increasing reflection of 1.18-1.26 mu m wave band, and the size is 4 multiplied by 10mm3(ii) a The output mirror 8 is a plano-concave mirror with 100mm radius of curvature, and the concave surface is plated with reflectivity to Stokes light>99.8% broadband dielectric film and broadband dielectric film partially transmitting 0.59-0.63 μm of first order frequency doubling light, and the plane is plated with 0.59-0.63 μm of transmissivity for first order frequency doubling light>99.8% of broadband dielectric film.
The distance L1 between the input mirror 4 and the left end face of the diamond crystal 5 is 48mm, the distance L2 between the right end face of the diamond crystal 5 and the first reflecting mirror 6 is 98mm, and the distance L3 between the first reflecting mirror 6 and the right end face of the first frequency doubling crystal 7 is 96 mm; the distance L4 between the left end face of the first frequency doubling crystal 7 and the output mirror 8 is 95 mm.
The shaping lens 9 is a lens group consisting of two convex lenses, and the two convex lenses are both plated with broadband dielectric films with high transmission of 0.59-0.63 mu m to the first-stage frequency doubling light.
Referring to fig. 3, the lock cavity frequency multiplier 10 comprises a lock cavity input mirror 10-1, a first lock cavity reflector 10-2, and a second lockA cavity reflector 10-3, a second frequency doubling crystal 10-4 and a lock cavity output mirror 10-5. The lock cavity input mirror 10-1 is a plane reflector, the left end is plated with an antireflection film with the transmission rate of 0.59-0.63 μm for the first-order frequency doubling light, and the right end is plated with a broadband dielectric film with the transmission rate of 2-4% for the first-order frequency doubling light with the transmission rate of 0.59-0.63 μm; the first lock cavity reflector 10-2 is a plane reflector coated with 0.59-0.63 μm reflectivity for the first-order frequency doubling light>99.9% of broadband dielectric film; the second lock cavity reflector 10-3 is a concave reflector with 100mm radius of curvature, and the left end of one side of the concave is plated with a reflectivity of 0.59-0.63 μm for the first-stage frequency doubling light>99.9% of broadband dielectric film; the second frequency doubling crystal 10-4 is a temperature phase matching LBO crystal with a cutting angle theta of 90 DEG and phi of 57 DEG, two ends of the second frequency doubling crystal are coated with antireflection films for the first order frequency doubling light in a wave band of 0.59-0.63 mu m, and the size of the second frequency doubling crystal is 4 multiplied by 10mm3(ii) a The lock cavity output mirror 10-5 is a concave reflector with 100mm curvature radius, and the left end of one side of the concave is plated with a reflectivity of 0.59-0.63 μm for the first-stage frequency doubling light>99.9% broadband dielectric film and 0.29-0.32 μm transmittance for second-stage frequency doubling light>90% broadband dielectric film, one side of the plane is plated with 0.29-0.32 μm transmittance to second-stage frequency doubling light>99.5% of broadband dielectric film.
The dichroic mirror 11 is coated with a broadband dielectric film with high transmissivity to the first-order frequency-doubled light of 0.59-0.63 μm and high reflection to the second-order frequency-doubled light of 0.29-0.32 μm.
After passing through the half wave plate 2, the focusing lens 3 and the input mirror 4, the pumping light is focused at the center of the diamond crystal 5, and the waist radius of the pumping light is 42 mu m. The efficiency of the focused pumping light is improved, and the non-target waveband light can be filtered more simply and conveniently. Frequency of omegaPThe pump light of (2) excites the ground state atoms of the diamond crystal 5 to a virtual Raman upper energy level and simultaneously generates a frequency of omegaSAnd one frequency is ωRAnd satisfies omegaP＝ωS+ωR. The Raman frequency shift of the diamond crystal 5 was 1332cm-1When the wavelength of the pump light is 1.02-1.08 μm, the wavelength of the excited Stokes light is 1.18-1.26 μm. The Stokes light oscillates in a Raman oscillator comprising an input mirror 4, a first mirror 6 and an output mirror 8, and the higher Stokes light power density in the cavity is obtained by interaction with a first frequency doubling crystal 7With Stokes light at a beam waist radius of 42 μm in the first frequency doubling crystal 7, the excitation frequency ω isD＝2ωRAfter the first-stage frequency doubling light is 0.59-0.63 mu m, the first-stage frequency doubling light omegaDOutput through an output mirror 8. First order frequency-doubled light omegaDAfter passing through a shaping lens 9, the light enters a cavity-locked frequency multiplier 10, is focused at the center of a second frequency doubling crystal 10-4, and excites omega2D＝2ωD0.29-0.32 μm and output via the lock cavity output mirror 10-5. Residual first order frequency doubled light omegaDAnd second order frequency doubling light omega2DAfter passing through the dichroic mirror 11, the first-stage frequency-doubled light with the wavelength of 0.59-0.63 μm is transmitted, and the second-stage frequency-doubled light with the wavelength of 0.29-0.32 μm is reflected, so that the separation effect is realized.
In summary, the embodiment of the present invention provides a single-pass pumping narrow-linewidth ultraviolet raman laser based on a V-cavity, which directly couples a laser with a wavelength of 1.02-1.08 μm output from a high power pump source into the V-cavity raman laser to achieve a high raman conversion efficiency of 1.18-1.26 μm and a laser output with a high frequency doubling conversion efficiency of 0.59-0.63 μm, and then achieves a narrow-linewidth and adjustable spectral width of the ultraviolet laser output of 0.29-0.32 μm through a cavity-locking frequency doubling structure.
Example 2
Referring to fig. 2 and 3, a narrow linewidth ultraviolet raman laser includes: the device comprises a pumping source 1, an optical isolator 12, a half-wave plate 2, a focusing lens 3, an input mirror 4, a diamond crystal 5, a first reflecting mirror 13 (in the embodiment, reference numeral 13 is used for representing the first reflecting mirror 6 in the embodiment 1), a first frequency doubling crystal 7, an output mirror 8, a second reflecting mirror 14, a shaping lens 9, a cavity-locking frequency multiplier 10 and a dichroic mirror 11.
Wherein, the output frequency of the pump source 1 is omegaPThe wavelength of the pump light in the linear polarization state is adjustable within 1.02-1.08 mu m, and the spectral line width<0.1 nm; the half wave plate 2 is used for adjusting the polarization state of the pump light; the optical isolator 12 is used for transmitting pump light in a single direction, and the light transmitted in a reverse direction cannot return to the pump source 1, so that the pump source 1 is protected; the focusing lens 3 is a broadband dielectric film plated with an anti-reflection film for the wavelength of the pump light of 1.02-1.08 mu m; the input mirror 4 is a plano-concave mirror with curvature radius of 50mm, and two surfaces of the plano-concave mirror are coated with broadband medium for increasing the transmission of the pump lightThe plasma membrane and the concave surface are plated with reflectivity of 1.18-1.26 mu m wave band for Stokes light>99.8% of broadband dielectric film; diamond crystal 5 is rim<110>Shaft-cut synthetic diamond crystals of size 7X 4X 1.2mm3Two end faces are plated with wave band transmittances of 1.02-1.08 mu m for pump light and 1.18-1.26 mu m for Stokes light>99.5% of broadband dielectric film; the first reflector 13 is a plano-concave mirror with a curvature radius of 100mm, and the concave surface is plated with a light transmittance for pump>98% broadband dielectric film and Stokes light reflectivity>99.8% broadband dielectric film, the plane is plated with pumping light transmittance>99.5% of broadband dielectric film, the included angle between the first reflector 13 and the incident pump light is 2 degrees; the second reflector 14 is a plano-concave mirror with a curvature radius of 100mm, and the concave surface is coated with a reflectivity to pump light>99% of broadband dielectric film; the first frequency doubling crystal 7 is a temperature phase matching LBO crystal with a cutting angle theta of 90 DEG and phi of 0 DEG, two ends of the first frequency doubling crystal are coated with broadband dielectric films for increasing the reflection of 1.18-1.26 mu m wave band, and the size of the first frequency doubling crystal is 4 multiplied by 10mm3(ii) a The output mirror 8 is a plano-concave mirror with the curvature radius of 100mm, and the concave surface is plated with the reflectivity for Stokes light>99.8% broadband dielectric film and broadband dielectric film partially transmitting 0.59-0.63 μm of first order frequency doubling light, and the plane is plated with 0.59-0.63 μm of transmissivity for first order frequency doubling light>99.8% of broadband dielectric film.
The distance L1 between the input mirror 4 and the left end face of the diamond crystal 5 is 48mm, the distance L2 between the right end face of the diamond crystal 5 and the first reflecting mirror 13 is 98mm, and the distance L3 between the first reflecting mirror 13 and the right end face of the first frequency doubling crystal 7 is 96 mm; the distance L4 between the left end face of the first frequency doubling crystal 7 and the output mirror 8 is 95 mm; the distance L5198 mm-202 mm between the first mirror 13 and the second mirror 14 is adjustable.
The shaping lens 9 is a lens group consisting of two convex lenses, and the two convex lenses are both plated with broadband dielectric films with high transmission of 0.59-0.63 mu m to the first-stage frequency doubling light.
The lock cavity frequency multiplier 10 consists of a lock cavity input mirror 10-1, a first lock cavity reflector 10-2, a second lock cavity reflector 10-3, a second frequency doubling crystal 10-4 and a lock cavity output mirror 10-5. The lock cavity input mirror 10-1 is a plane reflector, the left end is coated with an anti-reflection film with 0.59-0.63 μm for the first order frequency doubling light, and the right end is coated with a transmissivity with 0.59-0.63 μm for the first order frequency doubling light2-4% of broadband dielectric film; the first lock cavity reflector 10-2 is a plane reflector coated with 0.59-0.63 μm reflectivity for the first-order frequency doubling light>99.9% of broadband dielectric film; the second lock cavity reflector 10-3 is a concave reflector with 100mm radius of curvature, and the left end of one side of the concave is plated with a reflectivity of 0.59-0.63 μm for the first-stage frequency doubling light>99.9% of broadband dielectric film; the second frequency doubling crystal 10-4 is a temperature phase matching LBO crystal with a cutting angle theta of 90 DEG and phi of 57 DEG, both ends of the second frequency doubling crystal are plated with broadband dielectric films for increasing the reflection of 0.59-0.62 mu m wave band, and the size of the second frequency doubling crystal is 4 multiplied by 10mm3(ii) a The lock cavity output mirror 10-5 is a concave reflector with 100mm curvature radius, and the left end of one side of the concave is plated with a reflectivity of 0.59-0.63 μm for the first-stage frequency doubling light>99.9% broadband dielectric film and 0.29-0.32 μm transmittance for second-stage frequency doubling light>90% broadband dielectric film, one side of the plane is plated with 0.29-0.32 μm transmittance to second-stage frequency doubling light>99.5% of broadband dielectric film.
The dichroic mirror 11 is coated with a broadband dielectric film with high transmissivity to the first-order frequency-doubled light of 0.59-0.63 μm and high reflection to the second-order frequency-doubled light of 0.29-0.32 μm.
After passing through the half-wave plate 2, the optical isolator 12, the focusing lens 3 and the input mirror 4, the pump light is focused at the center of the diamond crystal 5, and the waist radius of the pump light is 42 μm. The efficiency of the focused pumping light is improved, and the non-target waveband light can be filtered more simply and conveniently. Frequency of omegaPThe pump light of (2) excites the ground state atoms of the diamond crystal 5 to a virtual Raman upper energy level and simultaneously generates a frequency of omegaSAnd one frequency is ωRAnd satisfies omegaP＝ωS+ωR. The Raman frequency shift of the diamond crystal 5 was 1332cm-1When the wavelength of the pump light is 1.02-1.08 μm, the wavelength of the excited Stokes light is 1.18-1.26 μm. The Stokes light oscillates in the raman oscillator composed of the input mirror 4, the first reflecting mirror 13 and the output mirror 8, and the residual pumping light penetrating through the first reflecting mirror 13 reenters and is focused in the diamond crystal 5 after being reflected by the second reflecting mirror 14, so that the utilization rate of the pumping light is improved. The Stokes light power density in the cavity is higher, and the beam waist radius of the Stokes light in the first frequency doubling crystal 7 is 42 through interaction with the first frequency doubling crystal 7μ m, excitation frequency ωD＝2ωRAfter the first-stage frequency doubling light is 0.59-0.63 mu m, the first-stage frequency doubling light omegaDOutput through an output mirror 8. First order frequency-doubled light omegaDAfter passing through a shaping lens 9, the light enters a cavity-locked frequency multiplier 10, is focused at the center of a second frequency doubling crystal 10-4, and excites omega2D＝2ωD0.29-0.32 μm and output via the lock cavity output mirror 10-5. Residual first order frequency-doubled light omegaDAnd second order frequency doubling light omega2DAfter passing through the dichroic mirror 11, the first-order frequency-doubled light with the wavelength of 0.59-0.63 μm is transmitted, and the second-order frequency-doubled light with the wavelength of 0.29-0.32 μm is reflected, so that the separation effect is achieved.
In summary, the embodiment of the present invention provides a two-way pumping narrow-linewidth ultraviolet raman laser based on a V-cavity, in which 1.02-1.08 μm laser output by a high power pump source is directly coupled into the V-cavity raman laser, and then the remaining pump light is coupled into the V-cavity raman laser by a second mirror 14, so as to perform secondary pumping on the pump light, thereby achieving high raman conversion efficiency of 1.18-1.26 μm and high frequency doubling conversion efficiency of 0.59-0.63 μm, and then achieving narrow-linewidth and adjustable spectral width of 0.29-0.32 μm ultraviolet laser output by a cavity-locking frequency doubling structure.
In the embodiment of the present invention, except for the specific description of the model of each device, the model of other devices is not limited, as long as the device can perform the above functions.
Those skilled in the art will appreciate that the drawings are only schematic illustrations of preferred embodiments, and the above-mentioned serial numbers of the embodiments of the present invention are only for description and do not represent the merits of the embodiments.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.
Claims (7)
1. A narrow linewidth ultraviolet raman laser, characterized in that the laser comprises:
the device comprises a pumping source, an optical isolator, a half-wave plate, a focusing lens, an input mirror, a diamond crystal, a first reflector, a first frequency doubling crystal, an output mirror, a second reflector, a shaping lens, a cavity-locking frequency multiplier and a dichroic mirror, wherein the input mirror, the first reflector and the output mirror form a V-shaped cavity structure; the diamond crystal is positioned between the input mirror and the first reflecting mirror, and the first frequency doubling crystal is positioned between the first reflecting mirror and the output mirror;
the lock cavity frequency multiplier consists of a lock cavity input mirror, a first lock cavity reflector, a second frequency doubling crystal and a lock cavity output mirror;
the pump source emits a first optical signal having a tunable first predetermined power and a first predetermined wavelength, i.e. having a frequency ωPThe pumping light passes through a half wave plate, an optical isolator, a focusing lens and an input mirror and is focused at the center of the diamond crystal, the pumping light excites the ground state atoms of the diamond crystal to a virtual Raman upper energy level to generate pumping light with a frequency of omegaSAnd a frequency of omegaRAnd satisfies omegaP＝ωS+ωR；
The diamond crystal is used for converting the first optical signal into a Stokes optical signal by utilizing an SRS effect; the Stokes optical signal oscillates in a Raman oscillator consisting of an input mirror, a first reflecting mirror and an output mirror, and the residual pumping light penetrating through the first reflecting mirror enters and focuses in the diamond crystal again after being reflected by a second reflecting mirror so as to improve the utilization rate of the pumping light;
the Stokes optical signal enters the first frequency doubling crystal through the first reflector, and after the first frequency doubling crystal excites the first-stage frequency doubling light, the first-stage frequency doubling light is output through the output mirror; the first-stage frequency doubling light enters the lock cavity frequency multiplier after passing through the shaping lens, is focused at the center of the second frequency doubling crystal, is excited to emit second-stage frequency doubling light, and is output through the lock cavity output mirror.
2. A narrow linewidth uv raman laser according to claim 1, wherein the reflectivities of the input mirror, the first mirror, and the output mirror are different.
3. A narrow linewidth ultraviolet Raman laser according to claim 1,
the focusing lens is a broadband dielectric film plated with an anti-reflection film for the wavelength of the pump light of 1.02-1.08 mu m;
the input mirror is a plano-concave mirror with the curvature radius of 50mm, two surfaces of the input mirror are plated with broadband dielectric films for increasing the reflection of the pump light, and the concave surface of the input mirror is plated with a broadband dielectric film with the reflectivity of 99.8% for the Stokes light in a wave band of 1.18-1.26 mu m;
the diamond crystal is a rim<110>Shaft-cut synthetic diamond crystals of size 7X 4X 1.2mm3Two end faces are plated with wave band transmittances of 1.02-1.08 mu m for pump light and 1.18-1.26 mu m for Stokes light>99.5% of broadband dielectric film;
the first reflector is a plano-concave mirror with the curvature radius of 100mm, the concave surface of the plano-concave mirror is plated with a broadband dielectric film with the light transmittance of pump being more than 98% and a broadband dielectric film with the light reflectance of Stokes being more than 99.8%, and the included angle between the first reflector and incident pump light is 2 degrees;
the first frequency doubling crystal is a temperature phase matching LBO crystal with a cutting angle theta of 90 DEG and phi of 0 DEG, two ends of the first frequency doubling crystal are plated with broadband dielectric films for increasing the reflection of Stokes light in a wave band of 1.18-1.26 mu m, and the first frequency doubling crystal is 4 multiplied by 10mm in size3；
The output mirror is a plano-concave mirror with the curvature radius of 100mm, the concave surface of the output mirror is plated with a broadband dielectric film which has the Stokes light reflectivity of more than 99.8 percent and partially transmits the first-stage frequency doubling light with the wavelength of 0.59-0.63 mu m, and the plane of the output mirror is plated with a broadband dielectric film which has the first-stage frequency doubling light transmittance of more than 99.8 percent and has the wavelength of 0.59-0.63 mu m.
4. A narrow linewidth ultraviolet Raman laser according to claim 1,
the lock cavity input mirror is a plane reflector, the left end of the lock cavity input mirror is plated with an antireflection film with the transmission rate of 0.59-0.63 mu m for the first-order frequency doubling light, and the right end of the lock cavity input mirror is plated with a broadband dielectric film with the transmission rate of 2-4% for the first-order frequency doubling light with the transmission rate of 0.59-0.63 mu m;
the first cavity-locked reflector is a plane reflector and is plated with a broadband dielectric film with the reflectivity of 99.9% to the first-stage frequency doubling light of 0.59-0.63 mu m;
the second lock cavity reflector is a plano-concave reflector with the curvature radius of 100mm, and the left end of one side of the concave surface is plated with a broadband dielectric film with the reflectivity of 99.9% to the first-stage frequency doubling light of 0.59-0.63 mu m;
the second frequency doubling crystal is a temperature phase matching LBO crystal with a cutting angle theta of 90 degrees and phi of 57 degrees, two ends of the second frequency doubling crystal are plated with broadband dielectric films which can increase the transmission of the first-stage frequency doubling light by 0.59-0.63 mu m, and the size of the second frequency doubling crystal is 4 multiplied by 10mm3；
The lock cavity output mirror is a plano-concave reflecting mirror with the curvature radius of 100mm, the left end of one side of a concave surface is plated with a broadband dielectric film with the reflectivity of more than 99.9% for the first-stage frequency doubling light of 0.59-0.63 mu m and the transmissivity of more than 90% for the second-stage frequency doubling light of 0.29-0.32 mu m, and the broadband dielectric film with the transmissivity of more than 99.5% for the second-stage frequency doubling light of 0.29-0.32 mu m is plated on one side of a plane.
5. A narrow line-width uv raman laser according to claim 1, wherein said second mirror is a plano-concave mirror with a radius of curvature of 100mm, the concave surface being coated with a broadband dielectric film having a reflectivity of > 99% for the pump light.
6. A narrow linewidth UV Raman laser according to claim 1,
directly coupling 1.02-1.08 mu m laser into a V-shaped cavity Raman laser, coupling the residual pump light into the V-shaped cavity Raman laser through a second reflecting mirror, and performing secondary pumping on the pump light to realize laser output with high Raman conversion efficiency of 1.18-1.26 mu m and high frequency doubling conversion efficiency of 0.59-0.63 mu m;
by the lock cavity frequency doubling structure, the output of ultraviolet laser with narrow line width and adjustable spectral width of 0.29-0.32 mu m is realized.
7. A narrow line width uv raman laser according to claim 1, wherein the distance between the first mirror and the second mirror is adjustable.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110625904.3A CN113381279B (en) | 2021-06-04 | 2021-06-04 | Narrow-linewidth ultraviolet Raman laser |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110625904.3A CN113381279B (en) | 2021-06-04 | 2021-06-04 | Narrow-linewidth ultraviolet Raman laser |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113381279A CN113381279A (en) | 2021-09-10 |
| CN113381279B true CN113381279B (en) | 2022-05-31 |
Family
ID=77575878
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110625904.3A Active CN113381279B (en) | 2021-06-04 | 2021-06-04 | Narrow-linewidth ultraviolet Raman laser |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113381279B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114300921B (en) * | 2021-12-20 | 2023-08-01 | 河北工业大学 | Multi-wavelength pulse laser for atmosphere detection |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1630967A (en) * | 2001-09-20 | 2005-06-22 | 费多尔·V·卡尔普什科 | Intracavity frequency conversion of laser radiation |
| CN1635670A (en) * | 2004-12-31 | 2005-07-06 | 西北大学 | Laser diode pumping full-solid ultraviolet pulse laser |
| CN202050155U (en) * | 2011-04-13 | 2011-11-23 | 山东大学 | Full-solid-state yellow light self-mode-locked Raman laser |
| CN103618205A (en) * | 2013-11-28 | 2014-03-05 | 清华大学 | Full-solid-state single longitudinal mode yellow light laser |
| CN105071214A (en) * | 2015-09-22 | 2015-11-18 | 山东大学 | Method for producing deep ultraviolet laser light through visible laser direct frequency conversion and all-solid-state deep ultraviolet laser |
| CN106229806A (en) * | 2016-09-27 | 2016-12-14 | 天津大学 | The tunable alaxadrite laser of Raman gold-tinted pumping |
-
2021
- 2021-06-04 CN CN202110625904.3A patent/CN113381279B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1630967A (en) * | 2001-09-20 | 2005-06-22 | 费多尔·V·卡尔普什科 | Intracavity frequency conversion of laser radiation |
| CN1635670A (en) * | 2004-12-31 | 2005-07-06 | 西北大学 | Laser diode pumping full-solid ultraviolet pulse laser |
| CN202050155U (en) * | 2011-04-13 | 2011-11-23 | 山东大学 | Full-solid-state yellow light self-mode-locked Raman laser |
| CN103618205A (en) * | 2013-11-28 | 2014-03-05 | 清华大学 | Full-solid-state single longitudinal mode yellow light laser |
| CN105071214A (en) * | 2015-09-22 | 2015-11-18 | 山东大学 | Method for producing deep ultraviolet laser light through visible laser direct frequency conversion and all-solid-state deep ultraviolet laser |
| CN106229806A (en) * | 2016-09-27 | 2016-12-14 | 天津大学 | The tunable alaxadrite laser of Raman gold-tinted pumping |
Also Published As
| Publication number | Publication date |
|---|---|
| CN113381279A (en) | 2021-09-10 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US5751751A (en) | Deep blue microlaser | |
| US20050190809A1 (en) | Ultraviolet, narrow linewidth laser system | |
| CN207782132U (en) | A kind of Solid State Laser array beam merging apparatus | |
| EP1005119B1 (en) | Compact multiple resonator laser system | |
| CN113381279B (en) | Narrow-linewidth ultraviolet Raman laser | |
| CN113725703A (en) | Raman laser oscillator with continuously tunable wavelength | |
| CN212725948U (en) | All-solid-state V-cavity Brillouin laser | |
| US7627008B2 (en) | Laser apparatus and method for harmonic beam generation | |
| CN111416263A (en) | Terahertz source based on phosphorus germanium zinc crystal non-collinear phase matching difference frequency | |
| CN113270785A (en) | Continuous wave 1.5 mu m human eye safety all-solid-state self-Raman laser | |
| US6833945B2 (en) | Rubidium titanyl arsenate-silver gallium selenide tandem optical parametric oscillator | |
| CN112397984A (en) | All-solid-state tunable blue-green laser based on self-sum frequency effect | |
| CN210201153U (en) | Medium-long wave infrared laser | |
| CN102044838A (en) | Stimulated Raman sum frequency laser wavelength conversion device | |
| CN217984056U (en) | High-stability dual-wavelength output single-frequency Raman laser | |
| KR950002068B1 (en) | Second harmonic generating system and method | |
| CN116487983A (en) | Yellow light self-frequency doubling laser | |
| CN111613963B (en) | Solid yellow laser | |
| CN220401096U (en) | High-power single-frequency intracavity five-time frequency laser | |
| CN112993729B (en) | Low-quantum-loss 1.6-micrometer high-peak-power pumping source of medium-wave optical parametric oscillator | |
| CN218070536U (en) | High-power nanosecond intracavity quintupling frequency laser | |
| CN210517318U (en) | Intracavity parametric oscillation and mixed frequency laser thereof | |
| JPH1195271A (en) | Optical parametric oscillator | |
| Eichler et al. | Design and construction of high-power solid state laser amplifiers with phase conjugating mirror | |
| CN110994336A (en) | High-efficiency tunable terahertz laser based on angle tuning |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |