A double-wavelength terahertz parametric generator with frequency multiplication relationship

Abstract

The application discloses a frequency-doubling relationship double-wavelength terahertz parametric generator and relates to the field of terahertz parametric generators, mainly comprising the following steps: first split pumped light after passing through a first reflection component and continuous seed light after passing through the first reflection component are injected into a first nonlinear crystal to generate first-order Stokes light and second-order Stokes light; the first-order Stokes light after passing through a second reflection component, the second-order Stokes light after passing through the second reflection component and the second pumped light after passing through a second split are injected into a second nonlinear crystal, and first terahertz light and second terahertz light are output on a high-resistance silicon prism. The two terahertz pulses generated by the application have high frequency stability, can keep accurate frequency-doubling relationship correlation, can realize equal power and same position output, and can realize a very small exit angle difference of the two frequency terahertz lights.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of terahertz parametric generator, in particular to a double-wavelength terahertz parametric generator with frequency multiplication relationship. BACKGROUND

[0002] Terahertz parametric technology, especially seed injection type terahertz parametric generator, is a kind of terahertz radiation source with high peak power, narrow linewidth, easy tuning and room temperature operation, and is one of the ideal terahertz light sources with the most practical potential, which can be widely applied to terahertz nondestructive testing, terahertz measurement, terahertz imaging, terahertz remote sensing, terahertz spectroscopy, terahertz biomedical and biological effect, etc.

[0003] The existing double-wavelength parametric technology is mainly based on terahertz parametric oscillator. Due to the characteristics of the prior art, it is difficult to generate double-wavelength terahertz pulses with MHz order accurate fixed frequency relationship. The injection seed is generated by parametric oscillation technology, which is difficult to achieve 5GHz in terahertz linewidth, cannot realize accurate tuning within 20GHz without mode jumping, and cannot realize the size adjustment and spatial coincidence of the output power of double-wavelength terahertz. SUMMARY

[0004] The purpose of the present application is to provide a double-wavelength terahertz parametric generator with frequency multiplication relationship, which can generate two beams of terahertz pulses with high frequency stability, maintain accurate frequency multiplication relationship, realize equal power and same position output, and realize the minimum exit angle difference of two frequency terahertz light.

[0005] To achieve the above purpose, the present application provides the following scheme:

[0006] The present application provides a double-wavelength terahertz parametric generator with frequency multiplication relationship, comprising: a pump light splitting assembly, a first propagation path, a second propagation path, a continuous seed light output assembly, a second nonlinear crystal and a high resistance silicon prism arranged on the second nonlinear crystal; wherein the length of the first propagation path and the length of the second propagation path are the same.

[0007] The pump light splitting assembly is used to generate first split pump light and second split pump light; the continuous seed light output assembly is used to generate continuous seed light.

[0008] The first reflection component, the first nonlinear crystal and the second reflection component are sequentially arranged on the first propagation path according to the transmission direction of the light, and the third reflection component is arranged on the second propagation path; wherein the first-order Stokes light and the second-order Stokes light are generated after the first split pumped light and the continuous seed light passing through the first reflection component are injected into the first nonlinear crystal; the first-order Stokes light passing through the second reflection component, the second-order Stokes light passing through the second reflection component and the second split pumped light passing through the third reflection component are injected into the second nonlinear crystal, and the first terahertz light and the second terahertz light are output on the high-resistance silicon prism.

[0009] Optionally, the pumped light splitting component comprises a pumped light source, a first half-wave plate and a first polarization beam splitter.

[0010] The pumped light source is configured to generate pumped light.

[0011] The first polarization beam splitter is configured to split the pumped light passing through the first half-wave plate into first split pumped light and second split pumped light.

[0012] Optionally, the continuous seed light output component comprises a continuous seed light source and a first mirror.

[0013] The continuous seed light source is configured to generate continuous seed light.

[0014] The first mirror is configured to reflect the continuous seed light into the first propagation path.

[0015] Optionally, the first reflection component comprises a second mirror and a third mirror; the second reflection component comprises a fourth mirror, a hole mirror and an attenuator.

[0016] The second mirror is configured to reflect the first split pumped light and inject it into the first nonlinear crystal.

[0017] The third mirror is configured to reflect the continuous seed light generated by the continuous seed light output component and inject it into the first nonlinear crystal.

[0018] The fourth mirror is configured to reflect the second-order Stokes light and inject it into the second nonlinear crystal.

[0019] The hole mirror is configured to reflect the first-order Stokes light attenuated by the attenuator and inject it into the second nonlinear crystal.

[0020] Optionally, the attenuator is configured to adjust the pulse energy of the first-order Stokes light, and further adjust the pulse energy of the first terahertz light, the pulse energy of the second terahertz light and the coupling output position of the first terahertz light and the second terahertz light.

[0021] Optionally, the first-pump light after the first splitting and the continuous seed light passing through the first reflective component generate first-order Stokes light and second-order Stokes light in the first nonlinear crystal through a first parametric process;

[0022] Wherein, the first parametric process is described as: the wave vector of the first-order Stokes light is expressed as represents the wave vector of the first-pump light after the first splitting, represents the wave vector of the THz light; the wave vector of the second-order Stokes light is expressed as

[0023] By adjusting the position of the third mirror, the incident angle of the continuous seed light into the first nonlinear crystal is adjusted, and the phase matching relationship in the first parametric process is satisfied.

[0024] Optionally, the first-order Stokes light passing through the second reflective component, the second-order Stokes light passing through the second reflective component, and the second-pump light after the second splitting passing through the third reflective component generate THz light in the second nonlinear crystal through a second parametric process, and the first THz light and the second THz light are coupled out on the high-resistance silicon prism;

[0025] Wherein, the second parametric process is described as: represents the wave vector of the second-pump light after the second splitting, represents the wave vector of the first THz light, represents the wave vector of the second THz light;

[0026] By adjusting the positions of the fourth mirror and the aperture mirror, the incident angles of the first-order Stokes light and the second-order Stokes light into the second nonlinear crystal are adjusted, and the phase matching relationship in the second parametric process is satisfied.

[0027] Optionally, the refractive index of the high-resistance silicon prism in the THz band is about 3.4, and the angle of the high-resistance silicon prism close to the tail of the second nonlinear crystal is 41°.

[0028] Optionally, the frequency relationship of the first THz light and the second THz light is v T2 = 2v T1 ;

[0029] Wherein, v T2 represents the frequency of the second THz light, and v T1 represents the frequency of the first THz light;

[0030] The included angle of the first terahertz light and the second terahertz light in the air is less than 0.3°.

[0031] The pulse line width of the first terahertz light and the second terahertz light is less than or equal to 5GHz.

[0032] Optionally, in the transmission direction of the light, the third reflection assembly comprises, in sequence, a second half-wave plate, a second polarization beam splitter, a ninth mirror, an eighth mirror, a seventh mirror, a sixth mirror and a fifth mirror.

[0033] The eighth mirror and the seventh mirror are located on the same horizontal line, and the sixth mirror and the ninth mirror are both located above the horizontal line.

[0034] The first distance and the second distance are adjusted so that the length of the first propagation path and the length of the second propagation path are the same, wherein the first distance is the distance between the eighth mirror and the ninth mirror, and the second distance is the distance between the seventh mirror and the sixth mirror.

[0035] According to the specific embodiments of the present application, the following technical effects are provided:

[0036] The present application utilizes the pump light pulse and the continuous wave seed light output by the continuous wave seed light source without mode hopping to generate 1st order Stokes light and 2nd order Stokes light in the first nonlinear crystal; the two beams of Stokes light are injected into the second nonlinear crystal as pulse seeds, and the terahertz wave is generated by the other pump light pulse, and is coupled out through the high-resistance silicon prism. The two beams of terahertz pulses generated have high frequency stability, can maintain the precise frequency-doubling relationship, can also realize equal power and same position output, and can realize the extremely small exit angle difference of the two frequency terahertz light. BRIEF DESCRIPTION OF DRAWINGS

[0037] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed in the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0038] Figure 1 It is a structural schematic diagram of a frequency-doubling relationship dual-wavelength terahertz parametric generator.

[0039] Symbol explanation:

[0040] 1. Pump source; 2. Pump light; 3. First half-wave plate; 4. First polarization beam splitter; 5. Second half-wave plate; 6. Second polarization beam splitter; 7. Continuous seed source; 8. Continuous seed light; 9. First mirror; 10. Second mirror; 11. Third mirror; 12. First nonlinear crystal; 13. First-order Stokes light; 14. Second-order Stokes light; 15. First light-blocking plate; 16. Attenuator; 17. Fourth mirror; 18. Perforated mirror; 19. Second nonlinear crystal; 20. High-resistivity silicon prism; 21. First terahertz light; 22. Second terahertz light; 23. Second light-blocking plate; 24. Fifth mirror; 25. Sixth mirror; 26. Seventh mirror; 27. Eighth mirror; 28. Ninth mirror; 29. ​​Third light-blocking plate; 30. Pump light after first beam splitting; 31. Pump light after second beam splitting. Detailed Implementation

[0041] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0042] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0043] Example 1

[0044] like Figure 1 As shown, this embodiment provides a frequency doubling relationship dual-wavelength terahertz parametric generator, including: a pump light beam splitter component, a first propagation path, a second propagation path, a continuous seed light output component, a second nonlinear crystal 19, and a high-resistivity silicon prism 20 disposed on the second nonlinear crystal 19; wherein, the length of the first propagation path and the length of the second propagation path are the same.

[0045] The pump light beam splitting assembly is used to generate the first split pump light 30 and the second split pump light 31; the continuous seed light output assembly is used to generate continuous seed light.

[0046] According to the direction of light transmission, a first reflective component, a first nonlinear crystal, and a second reflective component are sequentially arranged on the first propagation path, and a third reflective component is arranged on the second propagation path. The pump light after the first beam split by the first reflective component and the continuous seed light after the first reflective component are injected into the first nonlinear crystal 12 to generate first-order Stokes light 13 and second-order Stokes light 14. The first-order Stokes light after the second reflective component, the second-order Stokes light after the second reflective component, and the pump light after the second beam split by the third reflective component are injected into the second nonlinear crystal 19, and then output as first terahertz light 21 and second terahertz light 22 on the high-resistivity silicon prism 20.

[0047] In this embodiment, the pump light beam splitting assembly includes a pump source 1, a first half-wave plate 3, and a first polarization beam splitter 4; the pump source 1 is used to generate pump light 2; the first polarization beam splitter 4 is used to split the pump light passing through the first half-wave plate 3 into a first split pump light 30 and a second split pump light 31.

[0048] The first half-wave plate 3 and the first polarizing beam splitter 4 are combined to adjust the power of the pump light after the second beam split.

[0049] In this embodiment, the continuous seed light output component includes a continuous seed light source 7 and a first reflector 9; the continuous seed light source 7 is used to generate continuous seed light 8; the first reflector 9 is used to reflect the continuous seed light 8 into the first propagation path. The continuous seed light source is used to improve parametric efficiency and narrow the terahertz linewidth.

[0050] In this embodiment, the first reflecting component includes a second reflecting mirror 10 and a third reflecting mirror 11; the second reflecting component includes a fourth reflecting mirror 17, a perforated reflecting mirror 18, and an attenuator 16; the second reflecting mirror 10 is used to reflect the first split pump light 30 and inject it into the first nonlinear crystal 12; the third reflecting mirror 11 is used to reflect the continuous seed light generated by the continuous seed light output component and inject it into the first nonlinear crystal 12; the fourth reflecting mirror 17 is used to reflect the second-order Stokes light 14 and inject it into the second nonlinear crystal 19; the perforated reflecting mirror 18 is used to reflect the first-order Stokes light attenuated by the attenuator 16 into the second nonlinear crystal 19.

[0051] The attenuator 16 is used to adjust the pulse energy of the first-order Stokes light 13, that is, to control the intensity of the first-order Stokes light 13, and thereby adjust the pulse energy of the first terahertz light 21, the pulse energy of the second terahertz light 22, and the coupling output position of the first terahertz light 21 and the second terahertz light 22.

[0052] The pump light after being split by the first reflection component and the continuous seed light after being split by the first reflection component generate a first-order Stokes beam 13 and a second-order Stokes beam 14 in the first nonlinear crystal 12 through a first parametric process; wherein, the first parametric process is described as: the wave vector of the first-order Stokes beam Represented as This represents the wave vector of the pump light after the first beam split. Wave vector representing terahertz light; wave vector of second-order Stokes light Represented as

[0053] The incident angle of the continuous seed light entering the first nonlinear crystal 12 is adjusted by adjusting the position of the third reflector 11, thereby satisfying the phase matching relationship in the first parametric process.

[0054] In this embodiment, the pump light after passing through the second reflection component (first-order Stokes light), the second reflection component (second-order Stokes light), and the third reflection component (second beam splitting) undergoes a second parametric process in the second nonlinear crystal 19 to generate terahertz light, which is then coupled and output as first and second terahertz light on the high-resistivity silicon prism 20. The second parametric process is described as follows: This represents the wave vector of the pump light after the second beam split. The wave vector representing the first terahertz light, The wave vector representing the second terahertz light;

[0055] By adjusting the positions of the fourth reflector 17 and the perforated reflector 18, the incident angles of the first-order Stokes light and the second-order Stokes light entering the second nonlinear crystal 19 are adjusted, thereby satisfying the phase matching relationship in the second parametric process.

[0056] The third reflector 11, the fourth reflector 17, and the perforated reflector 18 are placed on a translation stage to control the angle between the continuous seed light and the angle between the first-order Stokes light passing through the second reflector and the second-order Stokes light passing through the second reflector, so as to satisfy the phase matching condition of the parametric process.

[0057] In this embodiment, the refractive index of the high-resistivity silicon prism 20 in the terahertz band is approximately 3.4, and the angle of the high-resistivity silicon prism near the tail of the second nonlinear crystal is 41°.

[0058] A high-resistivity silicon prism 20 is placed on a second nonlinear crystal 19 for coupling output of terahertz light and minimizing the difference in terahertz emission angles at different frequencies.

[0059] In this embodiment, the frequency relationship between the first terahertz light 21 and the second terahertz light 22 is v T2 =2v T1 ; where v T2 Representing the frequency of the second terahertz light, v T1 The frequency of the first terahertz light 21 is represented; the angle between the first terahertz light 21 and the second terahertz light 22 in air is less than 0.3°; the pulse linewidth of the first terahertz light 21 and the second terahertz light 22 is ≤5GHz.

[0060] In this embodiment, according to the direction of light transmission, the third reflecting component sequentially includes a second half-wave plate 5, a second polarizing beam splitter 6, a ninth reflecting mirror 28, an eighth reflecting mirror 27, a seventh reflecting mirror 26, a sixth reflecting mirror 25, and a fifth reflecting mirror 24; wherein the eighth reflecting mirror 27 and the seventh reflecting mirror 26 are located on the same horizontal line, and the sixth reflecting mirror 25 and the ninth reflecting mirror 28 are both located above the horizontal line. A first distance and a second distance are adjusted so that the length of the first propagation path and the length of the second propagation path are the same; wherein the first distance is the distance between the eighth reflecting mirror 27 and the ninth reflecting mirror 28, and the second distance is the distance between the seventh reflecting mirror 26 and the sixth reflecting mirror 25.

[0061] The second half-wave plate 5 and the second polarizing beam splitter 6 are combined to adjust the power of the pump light after the second beam split.

[0062] The eighth reflector 27 and the seventh reflector 26 are placed on the translation stage and act as delay lines to control the temporal overlap of the first-order Stokes light after passing through the second reflector, the second-order Stokes light after passing through the second reflector, and the pump light 31 after the second beam splitting after passing through the third reflector.

[0063] In this embodiment, the device further includes a first light-blocking plate 15, a second light-blocking plate 23, and a third light-blocking plate 29; the first light-blocking plate 15 is used to return pulse light output from the first nonlinear crystal 12 that is not on the first propagation path to the first nonlinear crystal 12; the second light-blocking plate 23 is used to return pulse light output from the second nonlinear crystal 19 that is not on the high-resistivity silicon prism 20 to the second nonlinear crystal 19; and the third light-blocking plate 29 is used to return pulse light output from the second polarization beam splitter 6 that is not on the first propagation path to the second polarization beam splitter 6.

[0064] Example 2

[0065] This embodiment provides a frequency doubling-relationship dual-wavelength terahertz parameter generator, the structure of which is as follows: Figure 1As shown. The implementation process of this dual-wavelength terahertz parameter generator with frequency doubling relationship is as follows:

[0066] Step 1: The 1064nm pulsed pump light 2 emitted from pump source 1 is split into a first split pump light 30 and a second split pump light 31. The first split pump light 30 is pumped into the first nonlinear crystal 12, and the continuous seed light 8 emitted from the continuous seed light source 7 is injected into the first nonlinear crystal 12. Specifically, by rotating the first half-wave plate 3, the splitting ratio of the first polarization beam splitter 4 is controlled, pumping the first split pump light 30 into the first nonlinear crystal 12 and the second split pump light 30 into the second nonlinear crystal 19. By rotating the second half-wave plate 5, the splitting ratio of the second polarization beam splitter 6 is controlled, thereby controlling the energy of the second split pump light 31.

[0067] Step 2: The pump light 30 after the first beam splitting and the continuous seed light 8 generate a first-order Stokes beam 13 and a second-order Stokes beam 14 in the first nonlinear crystal 12 through a parametric process. The parametric process is described as follows: in Let k be the wave vector. p =2π·v p k T =2π·v T k s =2π·v s v is the frequency, and p, T, and s represent pump light, terahertz light, and Stokes light, respectively.

[0068] First-order Stokes light Represented as 30 represents the pump light after the first beam split; second-order Stokes light. Represented as The third reflecting mirror 11 is fixed on the translation stage, and the direction of movement is as follows: Figure 1 As shown by the double arrows, the incident angle of the continuous seed light 8 is adjusted to meet the phase matching conditions in the above parametric process.

[0069] Step 3: First-order Stokes light 13 and second-order Stokes light 14 are injected as pulse seeds into the second nonlinear crystal 19, and together with the second split pump light 31, a parametric process is used to generate first terahertz light 21 and second terahertz light 22. The parametric process at this time is specifically expressed as follows: Therefore v T2 =2v T1By controlling the position and angle of the fourth reflector 17 and the perforated reflector 18, the phase matching conditions of their respective parametric processes are satisfied. By controlling the length of the delay line formed by the seventh reflector 26 and the eighth reflector 27, the pump light 31 after the second beam split is synchronized in time with the first-order Stokes light 13 and the second-order Stokes light 14.

[0070] Step 4: By adjusting the attenuation level of attenuator 16, the size and output position of the first terahertz light 21 and the second terahertz light 22 can be controlled. Optimally, the first terahertz light 21 and the second terahertz light 22 can be output with equal power and in the same position.

[0071] Step 5: Use a high-resistivity silicon prism to couple and output the first terahertz light 21 and the second terahertz light 22 to reduce the difference in the emission angle of terahertz light of different frequencies.

[0072] In this embodiment, pump source 1 includes a saturable absorber passively Q-switched laser and an amplification module. Pump light 2 has a wavelength of 1063.832 nm, a pulse width of 365 ps, a maximum pulse energy of 20 mJ / pulse, a repetition rate of 100 Hz, and a full width at half maximum (FWHM) of 1 mm. The pulse energy of pump light 30 after the first beam split is 6 mJ / pulse, and the pulse energy of pump light 31 after the second beam split is 9 mJ / pulse.

[0073] The continuous seed light source 7 includes a tunable external cavity semiconductor laser and an amplification module, with a tuning range of 1065nm-1085nm, a non-mode-hopping tuning range of 20GHz, and a linewidth of <1MHz. The continuous seed light 8 is a 400mW continuous light with a wavelength of 1069.520nm.

[0074] After being attenuated by attenuator 16, the first-order Stokes beam 13 has a pulse energy of 30 μJ and a pulse width of approximately 100 ps. The second-order Stokes beam 14 has a pulse energy of 30 μJ and a pulse width of 100 ps.

[0075] The first nonlinear crystal 12 is a c-LiNbO3 crystal with 5-mol% MgO and a size of 8mm*4mm*60mm; the second nonlinear crystal 19 is a s-LiNbO3 crystal with 1.3-mol% MgO and a size of 8mm*4mm*40mm.

[0076] The high-resistivity silicon prism 20 has a refractive index of approximately 3.4 in the terahertz band, and an angle of 41° near the tail of the second nonlinear crystal 19. The first terahertz light 21 has a frequency of 1.5 THz, a peak power of 12.6 kW, an output position approximately 0.4 mm from the front face of the second nonlinear crystal 19, and a linewidth of approximately 5 GHz; the second terahertz light 22 has a frequency of 3 THz, a peak power of 13 kW, an output position approximately 0.4 mm from the front face of the second nonlinear crystal 19, and a linewidth of approximately 5 GHz. After passing through the high-resistivity silicon prism 20, the angle between the first terahertz light 21 and the second terahertz light 22 in air is less than 0.3°.

[0077] In this embodiment, the first-order Stokes light and the second-order Stokes light generated during the parametric process have a fixed frequency relationship and are injected as pulse seeds into the second nonlinear crystal to generate dual-wavelength terahertz with a precise fixed overtone relationship on the order of MHz. The linewidth of the terahertz pulse is ≤5GHz.

[0078] This embodiment utilizes dual-frequency pulse seed injection technology to achieve fine tuning with narrow linewidth and continuous tuning within a 20GHz range without mode skipping; by leveraging the characteristics of parametric generation technology itself, it achieves the technical effects of controllable dual-frequency power, output position control and spatial overlap, and a dual-wavelength terahertz emission angle difference of <0.5° during the coupling output process.

[0079] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0080] This document uses specific examples to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the present invention. Furthermore, those skilled in the art will recognize that, based on the ideas of the present invention, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A frequency harmonic dual-wavelength terahertz parametric generator, characterized in that, include: The system comprises a pump light beam splitter, a first propagation path, a second propagation path, a continuous seed light output component, a second nonlinear crystal, and a high-resistivity silicon prism disposed on the second nonlinear crystal; wherein the lengths of the first propagation path and the second propagation path are the same. The pump light beam splitting assembly is used to generate pump light after the first beam split and pump light after the second beam split; the continuous seed light output assembly is used to generate continuous seed light. According to the direction of light transmission, a first reflective component, a first nonlinear crystal, and a second reflective component are sequentially arranged on the first propagation path, and a third reflective component is arranged on the second propagation path. The pump light after the first beam split by the first reflective component and the continuous seed light after the first reflective component are injected into the first nonlinear crystal to generate first-order Stokes light and second-order Stokes light. The first-order Stokes light, the second-order Stokes light, and the pump light after the second beam split by the second reflective component are injected into the second nonlinear crystal, and then output as first terahertz light and second terahertz light on a high-resistivity silicon prism. The second reflective component includes a fourth reflector, a perforated reflector, and an attenuator; by adjusting the positions of the fourth reflector and the perforated reflector, the incident angles of the first-order Stokes light and the second-order Stokes light entering the second nonlinear crystal are adjusted, thereby satisfying the phase matching relationship in the second parametric process.

2. The frequency harmonic dual-wavelength terahertz parametric generator according to claim 1, characterized in that, The pump beam splitter assembly includes a pump source, a first half-wave plate, and a first polarization beam splitter. The pump source is used to generate pump light; The first polarization beam splitter is used to split the pump light passing through the first half-wave plate into a first split pump light and a second split pump light.

3. The frequency harmonic dual-wavelength terahertz parametric generator according to claim 1, characterized in that, The continuous seed light output component includes a continuous seed light source and a first reflector; The continuous seed light source is used to generate continuous seed light; The first reflector is used to reflect the continuous seed light into the first propagation path.

4. The frequency harmonic dual-wavelength terahertz parametric generator according to claim 1, characterized in that, The first reflective component includes a second reflector and a third reflector; The second reflector is used to reflect the pump light after the first beam splitting and inject it into the first nonlinear crystal; The third reflector is used to reflect the continuous seed light generated by the continuous seed light output component and inject it into the first nonlinear crystal; The fourth mirror is used to reflect the second-order Stokes light and inject it into the second nonlinear crystal; The perforated mirror is used to reflect the first-order Stokes light, which has been attenuated by the attenuator, into the second nonlinear crystal.

5. A frequency harmonic dual-wavelength terahertz parametric generator according to claim 4, characterized in that, The attenuator is used to adjust the pulse energy of the first-order Stokes light, thereby adjusting the pulse energy of the first terahertz light, the pulse energy of the second terahertz light, and the coupling output position of the first terahertz light and the second terahertz light.

6. A frequency harmonic dual-wavelength terahertz parametric generator according to claim 4, characterized in that, The pump light after being split by the first reflection component and the continuous seed light after being split by the first reflection component generate first-order Stokes light and second-order Stokes light in the first nonlinear crystal through a first parametric process. The first parametric process is described as: the wave vector of a first-order Stokes light. Represented as This represents the wave vector of the pump light after the first beam split. Wave vector representing terahertz light; wave vector of second-order Stokes light Represented as The incident angle of the continuous seed light entering the first nonlinear crystal is adjusted by adjusting the position of the third reflector, thereby satisfying the phase matching relationship in the first parametric process.

7. A frequency harmonic dual-wavelength terahertz parametric generator according to claim 6, characterized in that, The pump light, after passing through the first-order Stokes light of the second reflection component, the second-order Stokes light of the second reflection component, and the second beam splitting of the third reflection component, generates terahertz light in the second nonlinear crystal through a second parametric process, and is coupled out on a high-resistivity silicon prism to output the first terahertz light and the second terahertz light. The second parameter process is described as follows: This represents the wave vector of the pump light after the second beam split. The wave vector representing the first terahertz light. The wave vector representing the second terahertz light; By adjusting the positions of the fourth reflector and the perforated reflector, the incident angles of the first-order Stokes light and the second-order Stokes light entering the second nonlinear crystal are adjusted, thereby satisfying the phase matching relationship in the second parametric process.

8. A frequency-harmonic dual-wavelength terahertz parametric generator according to claim 1 or 7, characterized in that, The high-resistivity silicon prism has a refractive index of approximately 3.4 in the terahertz band, and the angle of the high-resistivity silicon prism near the tail of the second nonlinear crystal is 41°.

9. A frequency harmonic dual-wavelength terahertz parametric generator according to claim 1, characterized in that, The frequency relationship between the first terahertz light and the second terahertz light is v T2 =2v T1 ; Among them, v T2 V represents the frequency of the second terahertz light. T1 This represents the frequency of the first terahertz light; The angle between the first terahertz light and the second terahertz light in air is less than 0.3°; The pulse linewidth of the first terahertz light and the second terahertz light is ≤5GHz.

10. A frequency harmonic dual-wavelength terahertz parametric generator according to claim 1, characterized in that, According to the direction of light transmission, the third reflecting component sequentially includes a second half-wave plate, a second polarizing beam splitter, a ninth reflecting mirror, an eighth reflecting mirror, a seventh reflecting mirror, a sixth reflecting mirror, and a fifth reflecting mirror; The eighth and seventh reflectors are located on the same horizontal line, and the sixth and ninth reflectors are both located above the horizontal line. Adjust the first distance and the second distance so that the length of the first propagation path and the length of the second propagation path are the same; wherein, the first distance is the distance between the eighth reflector and the ninth reflector, and the second distance is the distance between the seventh reflector and the sixth reflector.

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