WO2020220391A1 - 一种可见到紫外波段光学频率转换器 - Google Patents

一种可见到紫外波段光学频率转换器 Download PDF

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WO2020220391A1
WO2020220391A1 PCT/CN2019/086352 CN2019086352W WO2020220391A1 WO 2020220391 A1 WO2020220391 A1 WO 2020220391A1 CN 2019086352 W CN2019086352 W CN 2019086352W WO 2020220391 A1 WO2020220391 A1 WO 2020220391A1
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crystal
light
optical
frequency
visible
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PCT/CN2019/086352
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English (en)
French (fr)
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于浩海
张怀金
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山东大学
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Priority to JP2020519666A priority Critical patent/JP7006989B2/ja
Priority to EP19868170.2A priority patent/EP3851912B1/en
Priority to US16/843,204 priority patent/US10809594B2/en
Publication of WO2020220391A1 publication Critical patent/WO2020220391A1/zh

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    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
    • G02F1/35—Non-linear optics
    • G02F1/353—Frequency conversion, i.e. wherein a light beam is generated with frequency components different from those of the incident light beams
    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
    • G02F1/35—Non-linear optics
    • G02F1/3501—Constructional details or arrangements of non-linear optical devices, e.g. shape of non-linear crystals
    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
    • G02F1/35—Non-linear optics
    • G02F1/355—Non-linear optics characterised by the materials used
    • G02F1/3555—Glasses
    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
    • G02F1/35—Non-linear optics
    • G02F1/353—Frequency conversion, i.e. wherein a light beam is generated with frequency components different from those of the incident light beams
    • G02F1/3544—Particular phase matching techniques

Definitions

  • the invention relates to a nonlinear optical crystal device, in particular to an optical frequency converter in the visible to ultraviolet band, belonging to the technical field of lasers.
  • Non-linear optical frequency conversion is the realization of optical frequency up-conversion or down-conversion through the nonlinear response of materials to optics.
  • Frequency doubling uses its up-conversion effect to achieve the effect of doubling the optical frequency and doubling the wavelength. It is the most studied and widely used effect in the field of nonlinear optics.
  • the material basis of the frequency doubling effect is a nonlinear optical frequency conversion device. In this effect, the conservation of momentum, that is, the condition of phase matching, is the basic requirement for efficient optical frequency conversion.
  • the fundamental frequency light or e light and the frequency doubled light e light or o The refractive index of the light is equal, so as to achieve phase matching and high-efficiency frequency doubled light output.
  • lasers in the visible to ultraviolet band can be realized based on birefringence, and they are used in many fields related to the national economy and national security.
  • the phase matching method of crystal birefringence requires the crystal to have proper birefringence, which excludes most Crystals that do not have suitable birefringence limit the availability of high-efficiency lasers, especially the application of ultraviolet and even deep ultraviolet lasers.
  • Limited by the phase matching conditions only the layered potassium beryllium fluoroborate (KBBF) crystal achieves the effective frequency multiplication of deep ultraviolet, but its layered habit makes the crystal growth difficult, and the toxicity of the raw materials also greatly limits the crystal obtain.
  • KBBF layered potassium beryllium fluoroborate
  • the invention provides an optical frequency converter in the visible to ultraviolet band, which can realize frequency multiplication and sum frequency conversion from visible light to ultraviolet or even deep ultraviolet. .
  • the crystal used in the present invention is a non-linear optical crystal.
  • the crystal is cut in a certain direction according to the non-linear coefficient used, and the surface perpendicular to the tangential direction is polished and coated or not coated.
  • the crystal is destroyed by laser processing or ion beam etching.
  • the internal uniformity prevents the damage area from having an effective nonlinear effect and cannot achieve an effective frequency doubling process, but to achieve the phase change of the fundamental frequency light and the frequency doubling (or sum frequency) light, by controlling the fundamental frequency light and the frequency doubling light
  • the phase difference is used to adjust the phase of the light inside the crystal and achieve phase matching to obtain effective optical frequency conversion.
  • o Light Polarized light whose vibration direction is perpendicular to the main plane formed by the optical axis of the crystal and the incident direction.
  • e-light Polarized light whose vibration direction is parallel to the main plane formed by the optical axis of the crystal and the incident direction.
  • Ultraviolet light refers to light with a wavelength shorter than 400 nanometers.
  • Grating period the grating constant. As shown in Figure 2, the crystal is processed by laser processing, ion etching and other technologies to form gratings with different refractive index periodic arrangements inside the crystal.
  • the grating period ⁇ l c + l b , L c is the width of the unprocessed part of the crystal in the light-passing direction, and l b is the width of the processed part in the light-passing direction of the crystal.
  • An optical frequency conversion device in the visible to ultraviolet band using a nonlinear optical crystal, in which a periodic and regularly distributed amorphous region is arranged in the optical crystal; the amorphous region cannot achieve the coherent superposition of nonlinear optical effects, thereby blocking the multiplication
  • the conversion process from frequency light to fundamental frequency light but the amorphous region can provide the phase difference between fundamental frequency light and frequency doubled light.
  • the amorphous region provides a phase difference between the fundamental frequency light and the frequency doubled light m is an integer.
  • the periodically distributed amorphous region is a phase grating with a periodic distribution of refractive index perpendicular to the light passing direction, and the phase gratings are arranged in parallel along the crystal light passing direction, with one grating period
  • the transmission phase difference between the inner processing area and the unprocessed area is m is an integer.
  • the periodically distributed grating of the present invention includes both processed amorphous regions and unprocessed regions.
  • the refractive indices of these two parts are different, so the periodic distribution of refractive index is formed, and both parts can provide
  • the phase difference of odd multiples of ⁇ not only has the phase difference in the unprocessed part, but also has an effective nonlinear effect, that is, the continuous conversion of the fundamental frequency light to the frequency doubled light, and there is no effective nonlinear effect in the processed area, only the phase difference is provided .
  • the grating is obtained by processing crystals, that is, adding additional periodic phases; processing methods can be, but not limited to, laser micromachining, ion etching and other technologies that can achieve local crystal destruction.
  • a periodic and regularly distributed amorphous region is formed by destroying the structure of the crystal itself, so that the region has no nonlinear optical effect, thereby blocking the conversion process of frequency doubled light to fundamental frequency light, but this area can provide fundamental frequency light and frequency doubled light The phase difference of light.
  • the present invention utilizes laser processing, ion etching and other technologies to form gratings with different refractive index periodically arranged inside the crystal.
  • the phase difference between the fundamental frequency light and the frequency doubled light (or the sum frequency light) is realized by using the dispersion relationship between the refractive index of the processing area and the wavelength, so as to meet the phase matching and realize the efficient frequency doubled output.
  • the grating period ⁇ l c + l b of the present invention
  • l c is the width of the unprocessed part in the light passing direction of the crystal
  • l b is the width of the processed part in the light passing direction of the crystal.
  • the nonlinear optical crystal may be quartz (SiO 2 ) crystal, lithium triborate (LBO) crystal, barium metaborate ( ⁇ -BBO) crystal, strontium tetraborate (SBO) crystal, and niobic acid
  • Non-linear optical crystals such as lithium (LiNbO 3 ) crystals, potassium fluoroborate beryllate (KBBF) crystals, potassium dihydrogen phosphate (KDP) crystals, and barium magnesium fluoride (MgBaF 4 ) crystals, but are not limited to the above crystals.
  • the crystal is cut along a certain direction, and the surface perpendicular to the tangential direction is polished.
  • the periodic phase grating perpendicular to the light-passing direction is processed by laser lithography, ion etching and other techniques.
  • the length of the processing area is controlled and the additional periodic phase is provided to meet the phase matching condition and realize the frequency conversion from visible to ultraviolet and deep ultraviolet bands.
  • the surface of the non-linear optical crystal is coated with a dielectric film that transmits both the fundamental frequency light and the frequency doubled light or is not coated.
  • the length of the non-linear optical crystal in the light-passing direction is 0.1-100 mm, more preferably 3-10 mm, and the cross section of the crystal is round, square or any shape.
  • the method for manufacturing the above-mentioned visible to ultraviolet band optical frequency conversion device includes the following steps:
  • the nonlinear optical crystal is cut in a certain direction, and laser processing, ion etching and other techniques are used to form gratings with different refractive index periodically arranged inside the crystal; the structure of the crystal itself is destroyed to form an amorphous region with a regular distribution of periodicity.
  • the phase difference is m is an integer.
  • the present invention controls the phase of light when the light is transmitted inside the crystal by controlling the processing length of the grating in the light-passing direction.
  • phase difference between the fundamental frequency light and the frequency doubled light in the damaged area Phase difference with undamaged area Both are (2m+1) ⁇ , where m is an integer.
  • the additional periodic phase difference by controlling the damage area is So as to meet the phase matching condition and realize effective optical frequency conversion.
  • the application of the above-mentioned visible to ultraviolet band optical frequency conversion device in an optical frequency converter and further, an application of the visible to ultraviolet band optical frequency converter.
  • the above-mentioned optical frequency conversion device in the visible to ultraviolet band can also be used for a laser capable of realizing optical frequency conversion in the visible to ultraviolet band.
  • a laser capable of optical frequency conversion in the visible to ultraviolet band includes a pump source, an optical frequency conversion device, a prism and a detector arranged in order along the optical path; the optical frequency conversion device, the prism and the detector are arranged in Headgear box.
  • a focusing system is also arranged between the pump source and the optical frequency conversion device.
  • the pump source is a continuous laser pump source or a pulsed laser pump source
  • the prism is a calcium fluoride prism
  • the focusing system is a convex lens
  • the pump source when the above-mentioned optical frequency conversion laser in the visible to ultraviolet band is working, the pump source emits laser light, which can be focused by the focusing system and enter the optical frequency conversion device. Because the optical crystal in the optical frequency conversion device has a period inside the optical crystal Regularly distributed amorphous region; this amorphous region has no nonlinear optical effect, thereby blocking the conversion process of frequency-doubled light to fundamental frequency light, but this amorphous region can provide the phase difference between fundamental frequency light and frequency doubled light to make up for the non-linear optical effect.
  • the phase mismatch of the linear optical crystal is insufficient to realize efficient frequency doubling and sum frequency conversion; the converted laser enters the prism to separate light of different wavelengths for easy observation.
  • the prism separates the pump light and the frequency doubling light and enters the detector Detect the power or energy in the process to determine whether the optical frequency conversion is achieved.
  • the optical frequency conversion device, the prism and the detector are arranged in the headgear box to provide the process to be carried out in a vacuum or nitrogen environment.
  • the present invention adopts a nonlinear optical crystal, and an amorphous region with periodic regular distribution is arranged inside the optical crystal; the amorphous region has no nonlinear optical effect, thereby blocking the conversion process of frequency-doubled light to fundamental frequency light, but the amorphous region
  • the area can provide the phase difference between the fundamental frequency light and the frequency doubled light.
  • a phase grating with periodic refractive index distribution can be formed inside the nonlinear optical crystal by techniques such as laser processing and ion etching, so as to provide an additional periodic phase to compensate for the lack of phase mismatch of the nonlinear optical crystal, and to achieve efficient frequency doubling and Sum frequency conversion, especially for deep ultraviolet laser output.
  • the structure is simple, but the processing process is easy, and the optical frequency conversion from visible to ultraviolet band can be successfully realized.
  • the present invention has no special requirements on the structure of the nonlinear optical crystal, and all nonlinear optical crystals can be processed within the allowable range of their transmittance to realize optical frequency conversion from visible to ultraviolet band.
  • the present invention does not need to rely on additional effects, such as the effect of an electric field.
  • the optical frequency conversion from visible to ultraviolet can be realized only by processing periodic gratings in the crystal.
  • the method is very simple, the processing accuracy is high, and the controllability is strong. .
  • phase matching method of the additional periodic phase of the present invention can be optimized for nonlinear optical materials, such as selecting a crystal with a larger effective nonlinear coefficient or selecting a larger effective nonlinear coefficient of the crystal, thereby improving the frequency conversion efficiency.
  • the present invention can optimize different wavelengths, and only need to select an appropriate nonlinear crystal according to the required wavelength to provide matching additional periodic phases through laser lithography and other processes, and the frequency conversion of the corresponding wavelength can be realized.
  • FIG. 1 is a schematic diagram of the processing of the quartz crystal of Example 1.
  • 1 is the direction of the pump light source; 2 is the processing area, and X, Y, and Z are the optical spindles of the quartz crystal.
  • 2 is a schematic diagram of the periodic distribution of refractive index of the crystal of Example 1 after photolithography.
  • 3 is the pump light
  • 4 is the unprocessed part of the crystal with a refractive index of n 1 and a width of l c
  • 5 is the processed part of the crystal with a refractive index of n 2 and a width of l b
  • 6 is the frequency doubled output light.
  • FIG. 3 is a diagram of the experimental device in Example 1.
  • 7 is a pump source with a wavelength of 355nm
  • 8 is a focusing system
  • 9 is an optical frequency conversion device
  • 10 is a calcium fluoride prism, which can separate light of different wavelengths for easy observation
  • 11 is a pump light
  • 12 is The frequency doubled light separated by the prism
  • 13 is a detector, which can detect power and energy
  • 14 is a glove box, which provides a vacuum or nitrogen environment.
  • Fig. 4 is a laser output spectrum at 355nm frequency doubled at 177.3nm in Example 1.
  • the abscissa is the wavelength (nm) and the ordinate is the relative intensity.
  • Fig. 5 is a laser output spectrum of 426nm frequency doubled 213nm in Example 2, the abscissa is the wavelength (nm), and the ordinate is the relative intensity.
  • Fig. 6 is a laser output spectrum of 1540nm frequency doubled 770nm in Example 3.
  • the abscissa is the wavelength (nm), and the ordinate is the relative intensity.
  • Fig. 7 is a laser output spectrum of 1064nm and 532nm and a frequency of 355nm in Example 5.
  • the abscissa is the wavelength (nm), and the ordinate is the relative intensity.
  • Fig. 8 is a laser output spectrum of 532nm at 1064nm frequency doubled in Example 7.
  • the abscissa is the wavelength (nm), and the ordinate is the relative intensity.
  • Fig. 9 is a laser output spectrum of 484nm doubled at 242nm in Example 9.
  • the abscissa is the wavelength (nm), and the ordinate is the relative intensity.
  • Example 1 Quartz crystal deep ultraviolet wavelength 177.3nm frequency doubler converter
  • the preparation process of the optical frequency conversion device The quartz crystal is used as the nonlinear optical crystal.
  • the crystal processing method is shown in Figure 1. Using the maximum nonlinear coefficient d 11 , the quartz crystal is cut in the Z direction, and the laser is passed in the Z direction in the light transmission direction. Etching forms a grating structure with periodic refractive index distribution, in which the photoetched area provides additional periodic phase, and the width of the processed area and the unprocessed area are both 0.7 ⁇ m.
  • the additional period phase difference between the fundamental frequency light and the frequency doubled light that can be provided by the processing area is ⁇
  • the crystal length of the entire processing area is 1mm
  • the crystal cross section is 3mm ⁇ 3mm
  • the surface is polished.
  • the periodic arrangement of the refractive index is shown in Figure 2.
  • the experimental device is shown in Figure 3, which is composed of a pump source 7, a focusing system 8, an optical frequency conversion device 9, a calcium fluoride prism 10, and a detector 13 arranged in sequence along the optical path.
  • the optical frequency conversion device 9, the prism 10 and the detector 13 are arranged in the glove box 14.
  • the pump source 7 is an ultraviolet pulsed laser with a wavelength of 355nm with a pulse width of 6ns and a repetition rate of 10Hz;
  • the focusing system 8 is a focusing lens with a focal length of 10cm;
  • the glove box 14 can be provided by vacuuming to provide a vacuum environment or filling with nitrogen. A nitrogen environment reduces the absorption loss of the deep ultraviolet band in the air.
  • the calcium fluoride prism 10 separates the pump light and the frequency-doubled light according to the crystal dispersion equation, and the refractive index of the light waves of different wavelengths is different, so as to facilitate the effective output and use of the frequency-doubled light.
  • the pump source 7 emits laser light, which can be focused by the focusing system 8 and then enters the optical frequency conversion device 9. Because the optical crystal in the optical frequency conversion device 9 is provided with a periodic and regularly distributed amorphous region; the amorphous region has no nonlinearity Optical effect, thereby blocking the conversion process of frequency doubled light to fundamental frequency light, but the amorphous region can provide the phase difference between the fundamental frequency light and the frequency doubled light, make up for the lack of phase mismatch of the nonlinear optical crystal, and achieve high-efficiency frequency doubling and Sum frequency conversion; the converted laser light enters the prism 10 to separate light of different wavelengths for easy observation. The prism 10 separates the pump light 11 and the frequency doubled light 12, and enters the detector 13 to detect the power or energy to determine Whether the conversion of optical frequency is realized.
  • Example 2 Quartz crystal ultraviolet wavelength 213nm frequency doubler converter
  • the difference is: the pump source 7 is a pulsed laser with a wavelength of 426nm, the pulse width is 10ns, the repetition frequency is 50Hz, and the cross-section of the quartz crystal is 5 ⁇ 3mm.
  • the processing area and The width of the unprocessed area is 1.4 ⁇ m, and the phase difference between the fundamental frequency light and the frequency doubled light provided by the processed area is ⁇ .
  • the laser output with an ultraviolet wavelength of 213nm can be achieved.
  • the output wavelength is shown in Figure 5. .
  • Embodiment 3 Quartz crystal visible wavelength 770nm frequency doubler converter
  • the pump source 7 is a femtosecond pulsed laser with a wavelength of 1540nm, a pulse width of 500fs, a repetition frequency of 200MHz, a quartz crystal section of 4 ⁇ 4mm, a crystal length of 50mm, and a crystal
  • the surface is plated with a dielectric film that is highly transparent to 1540nm and 770nm. It does not require calcium fluoride prism spectroscopy and a glove box.
  • a grating structure with periodic refractive index distribution is formed by ion beam etching in the Z direction of light transmission.
  • the width of the processed area and the unprocessed area in the cycle are both 34.4 ⁇ m, the phase difference between the fundamental frequency light and the frequency doubled light is ⁇ , and the pump power can be increased to achieve a laser output with a visible wavelength of 770nm.
  • the output wavelength is shown in the figure 6 shown.
  • Embodiment 4 SBO crystal deep ultraviolet wavelength 177.3nm frequency double converter
  • the difference is: the nonlinear optical crystal is an SBO crystal, using the maximum nonlinear coefficient d 33 , the crystal is cut in the X direction, the cross section of the crystal is 3 ⁇ 4mm, the length of the crystal is 10mm, in the light direction A grating structure with periodic refractive index distribution is formed by laser etching in the X direction. The width of the processed and unprocessed areas in each period is 2.9 ⁇ m. The phase difference between the fundamental frequency light and the frequency doubled light that the processed area can provide is 5 ⁇ , increase the pump power, and realize the laser output with a deep ultraviolet wavelength of 177.3nm.
  • Example 5 LBO crystal ultraviolet wavelength 355nm sum frequency converter
  • the difference is: the nonlinear optical crystal is an LBO crystal, and the 355nm laser is generated by co-directional lasers with wavelengths of 1064nm and 532nm at the sum frequency.
  • the crystal is cut in the X direction.
  • the cross-section of the crystal is 5 ⁇ 5mm, and the length of the crystal is 20mm.
  • a grating structure with periodic refractive index distribution is formed by laser etching in the X direction of light transmission.
  • the width of the processed area and the unprocessed area in each period is 4.4 ⁇ m.
  • the phase difference between the fundamental frequency light and the sum frequency light that can be provided in the processing area is ⁇ , and the pump power can be increased to achieve a laser output with an ultraviolet wavelength of 355nm.
  • the output wavelength is shown in Figure 7.
  • Example 6 KBBF crystal ultraviolet wavelength 205nm frequency double converter
  • the difference is: the nonlinear optical crystal is a KBBF crystal, using the maximum nonlinear coefficient d 11 , the crystal is cut in the Z direction, the cross section of the crystal is 2 ⁇ 3mm, and the length of the crystal is 2.5mm.
  • a grating structure with periodic refractive index distribution is formed by laser etching, in which the width of the processed and unprocessed areas in each cycle is 1.6 ⁇ m, and the phase difference between the fundamental frequency light and the frequency doubled light that the processed area can provide It is ⁇
  • the pump source 7 is an optical parametric oscillator with a wavelength of 410 nm, with a pulse width of 20 ns and a repetition frequency of 20 Hz. Increasing the pump power can achieve laser output with an ultraviolet wavelength of 205 nm.
  • Example 7 LiNbO 3 crystal visible wavelength 532nm frequency doubler converter
  • the difference is: the nonlinear optical crystal is LiNbO 3 crystal, using the maximum nonlinear coefficient d 33 , the crystal is cut in the X direction, the pump source 7 is a continuous laser with a wavelength of 1064 nm, and the crystal cross section is Round, 10mm in diameter, the surface of the crystal is plated with a dielectric film that transmits 1064nm and 532nm. It does not require calcium fluoride prism spectroscopy and glove box. The length of the crystal is 20mm. It is formed by ion beam etching in the X direction of light transmission.
  • a grating structure with periodic refractive index distribution in which the width of the processed area in each period is 3.5 ⁇ m, and the width of the unprocessed area is 10.5 ⁇ m.
  • the phase difference between the fundamental frequency light and the frequency doubled light that the processed area can provide is ⁇
  • the phase difference between the fundamental frequency light and the frequency doubled light that can be provided by the processing area is 3 ⁇
  • the pump power can be increased to achieve a laser output with a visible wavelength of 532nm.
  • the output wavelength is shown in Figure 8.
  • Example 8 MgBaF 4 crystal ultraviolet wavelength 266nm frequency double converter
  • the difference is: the nonlinear optical crystal is MgBaF 4 crystal, using the maximum nonlinear coefficient d 32 , the crystal is cut in the X direction, and the pump source 7 is a pulsed laser with a wavelength of 532 nm, and its pulse width It is 50ns, the repetition frequency is 1kHz, the cross-section of the crystal is 6 ⁇ 6mm, and the length of the crystal is 30mm.
  • a grating structure with periodic refractive index distribution is formed by laser etching in the X direction of light transmission.
  • the processed area and unprocessed area in each cycle The area width is 10.7 ⁇ m, the phase difference between the fundamental frequency light and the frequency doubled light that can be provided by the processing area is 3 ⁇ , and the pump power can be increased to realize the laser output with an ultraviolet wavelength of 266nm.
  • Embodiment 9 ⁇ -BBO crystal ultraviolet wavelength 242nm frequency double converter
  • the difference is: the nonlinear optical crystal is a ⁇ -BBO crystal, using the maximum nonlinear coefficient d 22 , the crystal is cut in the Z direction, the cross section of the crystal is 3 ⁇ 4 mm, and the length of the crystal is 15 mm.
  • a grating structure with periodic refractive index distribution is formed by laser etching in the light direction Z direction, in which the width of the processed area and the unprocessed area in each period is 3.3 ⁇ m, and the phase of the fundamental frequency light and the frequency doubled light that the processed area can provide
  • the difference is 3 ⁇
  • the pump source 7 is a pulsed laser with a wavelength of 484nm, with a pulse width of 10ns and a repetition rate of 100Hz. Increasing the pump power can achieve a laser output with an ultraviolet wavelength of 242nm.
  • the output wavelength is shown in Figure 9.
  • the present invention provides a visible to ultraviolet band optical frequency converter by controlling the phase difference between the fundamental frequency and the frequency doubled light, which can realize the visible-ultraviolet-deep ultraviolet frequency doubled or sum frequency laser Output, especially for rare ultraviolet and deep ultraviolet crystal devices to provide new varieties.

Abstract

一种可见到紫外波段光学频率转换器。通过控制非线性光学晶体的加工周期提供附加周期相位满足相位匹配条件，从而实现有效光学频率转换。附加周期相位是通过激光微加工、离子刻蚀等技术于晶体内部形成不同折射率周期排布的相位光栅，由相位光栅中晶体周期性结构破坏来阻止非线性频率转换的逆过程并提供附加周期相位，弥补非线性光学晶体自然双折射不足造成的相位失配，实现有效的倍频或和频输出。可以对非线性光学材料进行优选，也可以根据所需波长选取适当晶体通过激光光刻等工艺提供与之匹配的附加周期相位，从而实现对特定波长的有效输出。为非线性光学频率转换器件提供新品种，具有光学频率转换效率高、易制备等优势。

Description

一种可见到紫外波段光学频率转换器 技术领域
本发明涉及非线性光学晶体器件，尤其涉及一种可见到紫外波段光学频率转换器，属于激光技术领域。
背景技术
非线性光学频率变换是通过材料对光学的非线性响应，实现光的频率上转换或者下转换，其中倍频是利用其上转换效应，以实现光学频率增加一倍、波长缩短一倍的效果，是非线性光学领域研究最多、应用最广泛的一种效应。倍频效应的材料基础是非线性光学频率转换器件。在该效应中，动量守恒即相位匹配条件是高效光学频率转换的基本要求，一般基于双折射效应的色散关系，以特殊切角下实现基频光o光或者e光与倍频光e光或者o光的折射率相等，从而实现相位匹配，实现高效倍频光输出。目前基于双折射已经可以实现可见到紫外波段激光，并在关系国民经济和国家安全的众多领域获得应用，但晶体的双折射的相位匹配方式，要求晶体具有合适的双折射，而排除了大部分不具有合适双折射的晶体，限制了高效激光的获得特别是紫外甚至深紫外激光方面的应用。受相位匹配条件的限制，只有层状氟硼酸铍钾(KBBF)晶体实现了深紫外的有效倍频，但由于其层状习性使得晶体生长困难，并且原料的毒性也极大的限制了晶体的获得。
发明内容
针对现有非线性光学频率转换技术和非线性光学材料的不足，发明提供一种可见到紫外波段光学频率转换器，该器件可实现从可见光到紫外甚至深紫外波段的倍频及和频频率转换。
发明概述：
本发明所用晶体为非线性光学晶体，根据所利用非线性系数将晶体沿着一定方向切割，垂直于切向的表面抛光并镀膜或不镀膜，以激光加工或者离子束刻蚀等方式，破坏晶体内部均匀性，使其破坏区域不具有有效非线性效应，无法实现有效倍频过程，而实现基频光和倍频(或和频)光的相位变化，通过控制基频光和倍频光的相位差，以调节晶体内部光的相位并实现相位匹配，获得有效光学频率转换。
术语说明：
o光：振动方向垂直于晶体光轴与入射方向构成的主平面的偏振光。
e光：振动方向平行于于晶体光轴与入射方向构成的主平面的偏振光。
紫外光：是指波长短于400纳米的光。
光栅周期：即光栅常数，如图2所示，通过采用激光加工、离子刻蚀等技术对晶体进行加工，于晶体内部形成不同折射率周期排布的光栅，光栅周期Λ＝l c+l b，l c是晶体通光方向未加工部分的宽度，l b是晶体通光方向加工部分的宽度。
本发明的技术方案如下：
一种可见到紫外波段光学频率转换器件，采用非线性光学晶体，所述光学晶体内部设置有周期规律分布的无定型区域；该无定型区域不能实现非线性光学效应的相干叠加，从而阻断倍频光到基频光的转换过程，但该无定型区域能提供基频光与倍频光的相位差。
根据本发明，优选的，所述的无定型区域提供基频光与倍频光的相位差
Figure PCTCN2019086352-appb-000001
m为整数。
根据本发明，优选的，所述的周期规律分布的无定型区域为垂直于通光方向的折射率周期性分布的相位光栅，所述的相位光栅沿晶体通光方向平行排布，一个光栅周期内加工区域和未加工区域传输的相位差均为
Figure PCTCN2019086352-appb-000002
m为整数。本发明的周期分布的光栅既包括加工的无定型区域，又包括未加工的区域，这两部分的折射率是不一样的，所以才会形成折射率的周期分布，而这两部分都可以提供π的奇数倍的相位差，在未加工部分不仅有相位差，还有有效非线性效应，即基频光向倍频光的持续转化，而在加工区域无有效非线性效应，只提供相位差。
根据本发明，优选的，所述的光栅是通过加工晶体的方式获得，即添加附加周期相位；加工方式可以但不限于激光微加工、离子刻蚀等可以实现晶体局域破坏的技术。
本发明通过破坏晶体本身的结构形成周期规律分布的无定型区域，使得该区域无非线性光学效应，从而阻断倍频光到基频光的转换过程，但该区域可以提供基频光与倍频光的相位差。
进一步的，本发明利用激光加工、离子刻蚀等技术于晶体内部形成不同折射率周期排布的光栅。利用加工区域的折射率随波长的色散关系实现基频光与倍频光(或和频光)的相位差，以满足相位匹配，实现高效倍频输出。
如图2所示，本发明的光栅周期Λ＝l c+l b，l c是晶体通光方向未加工部分的宽度，l b是晶体通光方向加工部分的宽度。通过控制通光方向上的光栅加工长度控制光在晶体内部传输时的相位，晶体在一个光栅周期内传输的相位差可以表示为
Figure PCTCN2019086352-appb-000003
其中Δk为非线性 光学晶体相位失配倒格矢量，Λ为光栅周期。优选的，未加工部分的宽度l c＝0.1-50μm，加工部分的宽度l b＝0.1-50μm。
根据本发明，优选的，所述非线性光学晶体可以采用石英(SiO 2)晶体、三硼酸锂(LBO)晶体、偏硼酸钡(β-BBO)晶体、四硼酸锶(SBO)晶体、铌酸锂(LiNbO 3)晶体、氟硼铍酸钾(KBBF)晶体、磷酸二氢钾(KDP)晶体、氟化钡镁(MgBaF 4)晶体等非线性光学晶体，但不仅限于上述晶体。根据所用非线性系数将晶体沿着一定方向切割，垂直于切向的表面抛光。沿着通光方向，通过激光光刻、离子刻蚀等技术加工垂直于通光方向的周期相位光栅。根据入射基频光波波长和非线性光学晶体的折射率色散方程，控制加工区域长度，提供附加周期相位，从而满足相位匹配条件，实现从可见到紫外、深紫外波段的频率转换。
根据本发明，优选的，所述的非线性光学晶体表面镀以对基频光和倍频光均高透过的介质膜或不镀膜。
根据本发明，优选的，所述的非线性光学晶体通光方向长度为0.1-100mm，进一步优选的是3-10mm，晶体的截面为圆形、方形或者任意形状。
根据本发明，优选的，上述可见到紫外波段光学频率转换器件的制备方法，包括步骤如下：
根据非线性系数将非线性光学晶体沿一定方向切割，利用激光加工、离子刻蚀等技术于晶体内部形成不同折射率周期排布的光栅；通过破坏晶体本身的结构形成周期规律分布的无定型区域，使得该区域无非线性光学效应，从而阻断倍频光到基频光的转换过程，但该区域能提供基频光与倍频光的相位差，相位差为
Figure PCTCN2019086352-appb-000004
m为整数。
如图2所示，本发明通过控制通光方向上的光栅加工长度控制光在晶体内部传输时的相位，晶体在一个光栅周期内传输的相位差可以表示为
Figure PCTCN2019086352-appb-000005
其中Δk为非线性光学晶体相位失配倒格矢量，Λ为晶体光栅周期，Λ＝l c+l b，l c是晶体通光方向未加工部分长度，l b是晶体通光方向加工破坏部分长度。通过改变破坏区域的加工长度，使得破坏区域基频光和倍频光的相位差
Figure PCTCN2019086352-appb-000006
和未破坏区域的相位差
Figure PCTCN2019086352-appb-000007
均为(2m+1)π，其中m为整数。通过控制破坏区域附加的周期相位差为
Figure PCTCN2019086352-appb-000008
从而满足相位匹配条件，实现有效的光学频率转换。
根据本发明，上述可见到紫外波段光学频率转换器件在光学频率转换器中的应用，进一步的，在可见到紫外波段光学频率转换器中的应用。
根据本发明，上述可见到紫外波段光学频率转换器件还可用于能实现可见到紫外波段光 学频率转换的激光器。
根据本发明，一种可见到紫外波段光学频率转换的激光器，包括沿光路依次设置的泵浦源、光学频率转换器件、棱镜和探测计；所述的光学频率转换器件、棱镜和探测计设置在头套箱中。
根据本发明的激光器，所述的泵浦源和光学频率转换器件之间还设置有聚焦系统。
根据本发明的激光器，优选的，所述的泵浦源连续激光泵浦源或脉冲激光泵浦源，所述的棱镜为氟化钙棱镜，所述的聚焦系统为凸透镜。
根据本发明，上述可见到紫外波段光学频率转换的激光器工作时，泵浦源发出激光，可通过聚焦系统聚焦后激光进入光学频率转换器件中，由于光学频率转换器件中的光学晶体内部设置有周期规律分布的无定型区域；该无定型区域无非线性光学效应，从而阻断倍频光到基频光的转换过程，但该无定型区域能提供基频光与倍频光的相位差，弥补非线性光学晶体相位失配不足，实现高效倍频及和频的转换；转换后的激光进入棱镜，将不同波长的光分开以便于观测，棱镜分出泵浦光和倍频光，进入到探测计中进行检测功率或能量以确定是否实现了光学频率的转换。其中光学频率转换器件、棱镜和探测计设置在头套箱中，以提供过程在真空或氮气环境中进行。
本发明的有益效果：
1、本发明采用非线性光学晶体，光学晶体内部设置有周期规律分布的无定型区域；该无定型区域无非线性光学效应，从而阻断倍频光到基频光的转换过程，但该无定型区域能提供基频光与倍频光的相位差。例如：可通过激光加工、离子刻蚀等技术在非线性光学晶体内部形成折射率周期性分布的相位光栅，从而提供一个附加周期相位，弥补非线性光学晶体相位失配不足，实现高效倍频及和频的转换，特别是可实现深紫外激光输出。不仅结构简单，而且加工过程容易，可成功实现从可见到紫外波段的光学频率转换。
2、本发明对于非线性光学晶体的结构无特别要求，对所有的非线性光学晶体在其透过率允许范围内均可能够加工实现从可见到紫外波段的光学频率转换。
3、本发明不需要借助额外的作用，例如：电场的作用，仅仅通过在晶体中加工周期性光栅即可实现从可见到紫外的光学频率转换，方法十分简单且加工精度高，可控性强。
4、本发明所述附加周期相位的相位匹配方式可以对非线性光学材料进行优选，如选取有效非线性系数较大的晶体或者选取晶体的较大的有效非线性系数，从而提高频率转换效率。
5、本发明可以对不同的波长进行优选，只需根据所需波长选取适当非线性晶体通过激 光光刻等工艺提供与之匹配的附加周期相位，便可实现相应波长的频率转换。
附图说明
为了更清楚地说明本发明实施例或现有技术中的技术方案，下面将对实施例中所需要使用的附图作简单地介绍，显而易见地，下面描述中的附图仅仅是本发明的一些实施例，对于本领域普通技术人员来讲，在不付出创造性劳动性的前提下，还可以根据这些附图获得其他的附图。
图1是实施例1的石英晶体加工示意图。其中，1是泵浦光源方向；2是加工区域，X、Y、Z为石英晶体光学主轴。
图2是实施例1的晶体光刻后折射率周期分布示意图。其中3是泵浦光；4是晶体未加工部分，折射率为n 1，宽度为l c；5是晶体加工部分，折射率为n 2，宽度为l b；光栅周期为Λ＝l c+l b；6是倍频输出光。
图3是实施例1中的实验装置图。其中，7是泵浦源，波长为355nm；8是聚焦系统；9是光学频率转换器件；10是氟化钙棱镜，可以将不同波长的光分开以便于观测；11是泵浦光；12是棱镜分出的倍频光；13是探测计，可探测功率和能量；14是手套箱，提供真空或者氮气环境。
图4是实施例1中355nm倍频177.3nm的激光输出图谱，横坐标是波长(nm),纵坐标是相对强度。
图5是实施例2中426nm倍频213nm的激光输出图谱，横坐标是波长(nm),纵坐标是相对强度。
图6是实施例3中1540nm倍频770nm的激光输出图谱，横坐标是波长(nm),纵坐标是相对强度。
图7是实施例5中1064nm和532nm和频355nm的激光输出图谱，横坐标是波长(nm),纵坐标是相对强度。
图8是实施例7中1064nm倍频532nm的激光输出图谱，横坐标是波长(nm),纵坐标是相对强度。
图9是实施例9中484nm倍频242nm的激光输出图谱，横坐标是波长(nm),纵坐标是相对强度。
具体实施方式
下面结合附图和实施例对本发明做进一步说明，但不限于此。
实施例1：石英晶体深紫外波长177.3nm倍频转换器
光学频率转换器件的制备过程：采用石英晶体作为非线性光学晶体，晶体加工方式如图1所示，利用最大非线性系数d 11，石英晶体按Z方向切割，在通光方向Z方向上通过激光刻蚀形成折射率周期性分布的光栅结构，其中光刻区域提供附加周期相位，其中加工区域和未加工区域宽度均为0.7μm。加工区域可提供的基频光与倍频光的附加周期相位差为π，整个加工区间晶体长度为1mm，晶体截面为3mm×3mm，表面抛光。折射率的周期排布如图2所示。
实验装置如图3所示，由泵浦源7、聚焦系统8、光学频率转换器件9、氟化钙棱镜10、探测计13沿光路顺序依次排列而成。光学频率转换器件9、棱镜10和探测计13设置在手套箱14中。
泵浦源7是波长为355nm的紫外脉冲激光器，其脉冲宽度为6ns，重复频率为10Hz；聚焦系统8是焦距为10cm的聚焦镜；手套箱14可以通过抽真空提供一个真空环境或者充氮气提供一个氮气环境，减少深紫外波段在空气中的吸收损耗。氟化钙棱镜10是根据晶体色散方程，不同波长的光波在晶体中的折射率不同，将泵浦光和倍频光波分出来，方便倍频光的有效输出和运用。
泵浦源7发出激光，可通过聚焦系统8聚焦后激光进入光学频率转换器件9中，由于光学频率转换器件9中的光学晶体内部设置有周期规律分布的无定型区域；该无定型区域无非线性光学效应，从而阻断倍频光到基频光的转换过程，但该无定型区域能提供基频光与倍频光的相位差，弥补非线性光学晶体相位失配不足，实现高效倍频及和频的转换；转换后的激光进入棱镜10，将不同波长的光分开以便于观测，棱镜10分出泵浦光11和倍频光12，进入到探测计13中进行检测功率或能量以确定是否实现了光学频率的转换。
加大泵浦功率，可实现深紫外177.3nm激光输出，输出波长如图4所示。
实施例2：石英晶体紫外波长213nm倍频转换器
如实施例1所述，所不同的是：泵浦源7为波长426nm的脉冲激光器，其脉冲宽度为10ns，重复频率为50Hz，石英晶体截面为5×3mm，其中每个周期内加工区域和未加工区域宽度均为1.4μm，加工区域可提供的基频光与倍频光的相位差为π，加大泵浦功率，可实现紫外波长为213nm的激光输出，输出波长如图5所示。
实施例3：石英晶体可见波长770nm倍频转换器
如实施例1所示，所不同的是，泵浦源7为波长为1540nm的飞秒脉冲激光器，脉冲宽度为500fs，重复频率为200MHz，石英晶体截面为4×4mm，晶体长度为50mm，晶体表面镀以对1540nm和770nm高透过的介质膜，不需要氟化钙棱镜分光和手套箱，在通光方向Z 方向上通过离子束刻蚀形成折射率周期性分布的光栅结构，其中每个周期内加工区域和未加工区域宽度均为34.4μm，所实现的基频光与倍频光的相位差为π，加大泵浦功率，可实现可见波长为770nm的激光输出，输出波长如图6所示。
实施例4：SBO晶体深紫外波长177.3nm倍频转换器
如实施例1所述，所不同的是：非线性光学晶体为SBO晶体，利用最大非线性系数d 33，晶体按X方向切割，晶体截面为3×4mm，晶体长度为10mm，在通光方向X方向上通过激光刻蚀形成折射率周期性分布的光栅结构，其中每个周期内加工区域和未加工区域宽度均为2.9μm，加工区域可提供的基频光与倍频光的相位差为5π，加大泵浦功率，可实现深紫外波长为177.3nm的激光输出。
实施例5：LBO晶体紫外波长355nm和频转换器
如实施例1所述，所不同的是：非线性光学晶体为LBO晶体，通过波长为1064nm和532nm的共向激光和频产生355nm激光，利用最大非线性系数d 32，晶体按X方向切割，晶体截面为5×5mm，晶体长度为20mm，在通光方向X方向上通过激光刻蚀形成折射率周期性分布的光栅结构，其中每个周期内加工区域和未加工区域的宽度均为4.4μm，加工区域可提供的基频光与和频光的相位差为π，加大泵浦功率，可实现紫外波长为355nm的激光输出,输出波长如图7所示。
实施例6：KBBF晶体紫外波长205nm倍频转换器
如实施例1所述，所不同的是：非线性光学晶体为KBBF晶体，利用最大非线性系数d 11，晶体按Z方向切割，晶体截面为2×3mm，晶体长度为2.5mm，在通光方向Z方向上通过激光刻蚀形成折射率周期性分布的光栅结构，其中每个周期内加工区域和未加工区域宽度均为1.6μm，加工区域可提供的基频光与倍频光的相位差为π，泵浦源7为波长410nm的光参量振荡器，其脉冲宽度为20ns，重复频率为20Hz，加大泵浦功率，可实现紫外波长为205nm的激光输出。
实施例7：LiNbO 3晶体可见波长532nm倍频转换器
如实施例1所述，所不同的是：非线性光学晶体为LiNbO 3晶体，利用最大非线性系数d 33，晶体按X方向切割，泵浦源7为波长为1064nm的连续激光器，晶体截面为圆形，直径10mm，晶体表面镀以对1064nm和532nm高透过的介质膜，不需要氟化钙棱镜分光和手套箱，晶体长度为20mm，在通光方向X方向上通过离子束刻蚀形成折射率周期性分布的光栅结构，其中每个周期内加工区域的宽度为3.5μm，未加工区域宽度均为10.5μm，加工区域可提供的基频光与倍频光的相位差为π，未加工区域可提供的基频光与倍频光的相位差为3π， 加大泵浦功率，可实现可见波长为532nm的激光输出，输出波长如图8所示。
实施例8：MgBaF 4晶体紫外波长266nm倍频转换器
如实施例1所述，所不同的是：非线性光学晶体为MgBaF 4晶体，利用最大非线性系数d 32，晶体按X方向切割，泵浦源7为波长为532nm的脉冲激光器，其脉冲宽度为50ns，重复频率为1kHz，晶体截面6×6mm，晶体长度为30mm，在通光方向X方向上通过激光刻蚀形成折射率周期性分布的光栅结构，其中每个周期内加工区域和未加工区域宽度均为10.7μm，加工区域可提供的基频光与倍频光的相位差为3π，加大泵浦功率，可实现紫外波长为266nm的激光输出。
实施例9：β-BBO晶体紫外波长242nm倍频转换器
如实施例1所述，所不同的是：非线性光学晶体为β-BBO晶体，利用最大非线性系数d 22，晶体按Z方向切割，晶体截面为3×4mm，晶体长度为15mm，在通光方向Z方向上通过激光刻蚀形成折射率周期性分布的光栅结构，其中每个周期内加工区域和未加工区域宽度均为3.3μm，加工区域可提供的基频光与倍频光的相位差为3π，泵浦源7为波长484nm的脉冲激光器，其脉冲宽度为10ns，重复频率为100Hz，加大泵浦功率，可实现紫外波长为242nm的激光输出，输出波长如图9所示。
而且，由以上实施例可知，本发明通过控制基频和倍频光的相位差，提供了一种可见到紫外波段光学频率转换器，可以实现可见-紫外-深紫外的倍频或和频激光输出，特别是为稀缺的紫外和深紫外晶体器件提供了新品种。

Claims (9)

  1. 一种可见到紫外波段光学频率转换器件，其特征在于，该光学频率转换器件采用非线性光学晶体，所述光学晶体内部设置有周期规律分布的无定型区域；该无定型区域不能实现非线性光学效应的相干叠加，从而阻断倍频光到基频光的转换过程，但该无定型区域能提供基频光与倍频光的相位差。
  2. 根据权利要求1所述的可见到紫外波段光学频率转换器件，其特征在于，所述的无定型区域提供基频光与倍频光的相位差
    Figure PCTCN2019086352-appb-100001
    m为整数。
  3. 根据权利要求1所述的可见到紫外波段光学频率转换器件，其特征在于，所述的周期规律分布的无定型区域为垂直于通光方向的折射率周期性分布的相位光栅，所述的相位光栅沿晶体通光方向平行排布，一个光栅周期内加工区域和未加工区域传输的相位差均为
    Figure PCTCN2019086352-appb-100002
    m为整数；
    所述的相位光栅是通过对晶体进行加工，于晶体内部形成不同折射率周期排布的光栅，光栅周期Λ＝l c+l b，l c是一个周期内晶体通光方向未加工部分的宽度，l b是晶体通光方向加工部分的宽度。
  4. 根据权利要求3所述的可见到紫外波段光学频率转换器件，其特征在于，对晶体加工的方式为激光微加工或离子刻蚀等。
  5. 根据权利要求3所述的可见到紫外波段光学频率转换器件，其特征在于，未加工部分的宽度l c＝0.1-50μm，加工部分的宽度l b＝0.1-50μm。
  6. 根据权利要求1所述的可见到紫外波段光学频率转换器件，其特征在于，所述非线性光学晶体可以但不限于采用石英晶体、三硼酸锂晶体、偏硼酸钡晶体、四硼酸锶晶体、铌酸锂晶体、氟硼铍酸钾晶体、磷酸二氢钾晶体或氟化钡镁晶体。
  7. 根据权利要求1所述的可见到紫外波段光学频率转换器件，其特征在于，所述的非线性光学晶体表面镀以对基频光和倍频光均高透过的介质膜或不镀膜。
  8. 根据权利要求1所述的可见到紫外波段光学频率转换器件，其特征在于，所述的非线性光学晶体通光方向长度为0.1-100mm，进一步优选的为3-10mm。
  9. 根据权利要求1所述的可见到紫外波段光学频率转换器件，其特征在于，所述的非线性光学晶体的截面为圆形、方形或其他任意形状。
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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114371583A (zh) * 2021-12-29 2022-04-19 华南理工大学 一种基于单块非线性晶体的飞秒激光超宽带高效率倍频器
CN116435860A (zh) * 2023-03-17 2023-07-14 山东大学 一种adp深紫外倍频器及深紫外宽波段倍频可调谐激光器

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US11255797B2 (en) 2019-07-09 2022-02-22 Kla Corporation Strontium tetraborate as optical glass material
US11237455B2 (en) 2020-06-12 2022-02-01 Kla Corporation Frequency conversion using stacked strontium tetraborate plates
CN114185223B (zh) * 2020-09-15 2024-03-26 山东大学 一种参量光的产生方法及应用
US11567391B1 (en) 2021-11-24 2023-01-31 Kla Corporation Frequency conversion using interdigitated nonlinear crystal gratings
CN114336259B (zh) * 2022-01-07 2024-01-26 山东大学 一种紫外宽波段调谐频率转换方法、器件和激光器

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1600906A (zh) * 2003-09-28 2005-03-30 中国科学院理化技术研究所 大尺寸磷酸硼非线性光学晶体及其熔盐生长方法和用途
CN101162828A (zh) * 2007-11-28 2008-04-16 福州高意通讯有限公司 一种腔内倍频激光器
CN101302647A (zh) * 2008-01-21 2008-11-12 中国科学院新疆理化技术研究所 大尺寸硼酸钡铋非线性光学晶体及其制备方法
CN101446735A (zh) * 2008-12-01 2009-06-03 中国科学院新疆理化技术研究所 四水合硼酒石酸锶铵非线性光学材料及其制备方法和用途
US20150085349A1 (en) * 2012-01-06 2015-03-26 Institute Of Physics, Chinese Academy Of Sciences Nonlinear optical device manufactured with 4h silicon carbide crystal

Family Cites Families (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2783047B2 (ja) * 1992-03-27 1998-08-06 松下電器産業株式会社 光波長変換素子およびそれを用いたレーザ光源
CN1218448C (zh) * 2000-10-11 2005-09-07 南京大学 双周期结构的超晶格及其在激光变频中的应用
GB0123740D0 (en) 2001-10-03 2001-11-21 Qinetiq Ltd Non-Linear Optical Devices
US6900928B2 (en) * 2002-03-19 2005-05-31 Hc Photonics Corporation Method of patterning and fabricating poled dielectric microstructures within dielectric materials
US7436579B1 (en) * 2006-09-08 2008-10-14 Arasor Corporation Mobile charge induced periodic poling and device
JP2011515713A (ja) * 2008-03-25 2011-05-19 イェダ リサーチ アンド デベロップメント カンパニー リミテッド 光変換用の結晶
BRPI0901016A2 (pt) * 2009-03-12 2009-11-17 Navin Bhailalbhai Patel dispositivo óptico não-linear usando materiais cúbicos não centrosimétricos para conversão de frequência
US8743922B2 (en) * 2011-10-21 2014-06-03 Sharp Kabushiki Kaisha Ultraviolet laser
JP6104376B2 (ja) 2013-06-06 2017-03-29 三菱電機株式会社 導波路型レーザ装置
CN103956644A (zh) * 2014-05-16 2014-07-30 中国科学院福建物质结构研究所 基于周期性极化反转晶体直腔连续紫外激光器
US11009773B2 (en) * 2017-08-11 2021-05-18 Shenzhen University Dual-chirped spectral optical parametric amplifier and amplification method

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1600906A (zh) * 2003-09-28 2005-03-30 中国科学院理化技术研究所 大尺寸磷酸硼非线性光学晶体及其熔盐生长方法和用途
CN101162828A (zh) * 2007-11-28 2008-04-16 福州高意通讯有限公司 一种腔内倍频激光器
CN101302647A (zh) * 2008-01-21 2008-11-12 中国科学院新疆理化技术研究所 大尺寸硼酸钡铋非线性光学晶体及其制备方法
CN101446735A (zh) * 2008-12-01 2009-06-03 中国科学院新疆理化技术研究所 四水合硼酒石酸锶铵非线性光学材料及其制备方法和用途
US20150085349A1 (en) * 2012-01-06 2015-03-26 Institute Of Physics, Chinese Academy Of Sciences Nonlinear optical device manufactured with 4h silicon carbide crystal

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See also references of EP3851912A4 *

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114371583A (zh) * 2021-12-29 2022-04-19 华南理工大学 一种基于单块非线性晶体的飞秒激光超宽带高效率倍频器
CN116435860A (zh) * 2023-03-17 2023-07-14 山东大学 一种adp深紫外倍频器及深紫外宽波段倍频可调谐激光器
CN116435860B (zh) * 2023-03-17 2024-05-03 山东大学 一种adp深紫外倍频器及深紫外宽波段倍频可调谐激光器

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