Micro-nano vibration laser interference dynamics measurement optimization method based on polarization enhancement

Abstract

The invention provides a micro-nano vibration laser interference dynamics measurement optimization method based on polarization enhancement, which is based on a polarization control system and comprises a laser generator, a reflector, a half slide, a polarization beam splitting cubic mirror, an objective lens, a micro-nano electromechanical resonator, a convex lens, a photoelectric detector, a spectrum analyzer, a network analyzer, a blue laser generator and a long-wave pass filter. Wherein a first quarter-wave slide is arranged between the laser generator and the reflector, a second quarter-wave slide is arranged between the reflector and the half-wave slide, and a third quarter-wave slide is arranged between the polarization beam splitting cubic mirror and the objective lens. According to the optical path enhancement technology based on polarization optimization, the input laser energy is utilized to the maximum extent, and the transmission loss of the laser in the optical path is reduced. The weak response signal of the micro-nano electromechanical resonator in a non-driving thermal vibration state is successfully and substantially amplified and purified, and a better measurement method is provided for deeply researching the dynamic characteristics of the micro-nano electromechanical resonator.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of laser application, and relates to a micro-nano vibration laser interference dynamics measurement optimization method based on polarization enhancement, which focuses on the movement measurement of a micro-nano mechanical resonant cavity of a Fabry-Perot structure by using a laser. BACKGROUND

[0002] The micro-nano electromechanical resonator has the advantages of micro-nano size, high frequency, high quality factor, low power consumption, good integrability, high sensitivity to physical quantities such as speed, mass and temperature, and small size effect, and is widely applied in the fields of sensors and signal processing, such as gas sensors, displacement sensors, and solar blind ultraviolet detectors.

[0003] Since the movement amplitude of the micro-nano resonator is only nanometers or even smaller, the movement direction reaches the size of an atom, and at this time, the traditional method for detecting a larger micro-nano resonator will no longer be applicable. In order to accurately measure the mechanical movement of the resonator, its performance should be deeply studied, and the method for measuring the micro-nano electromechanical resonator is divided into two categories: optical detection and electrical detection.

[0004] In optical detection, the most commonly used detection technology is laser interference measurement technology, which becomes the most commonly used technology for measuring micro-nano electromechanical resonators due to its simple operation, strong controllability and sensitive detection. The technology is very sensitive to device movement and has a sensitivity of fm / Hz-1 / 2 at room temperature, so it can measure non-driven thermal mechanical movement.

[0005] However, the traditional non-driven laser interference measurement method has inherent bottlenecks: the limited output power of the laser suffers unavoidable scattering, reflection and absorption loss in the complex optical transmission, and the effective light intensity reaching the photodetector is significantly attenuated, of which at least 75% of the energy is lost in the transmission path. This directly leads to extremely weak resonator vibration signals received by the detector, and the signal-to-noise ratio (SNR) is sharply reduced - the key resonance peak is submerged in the background noise, the measurement accuracy and detectability of the resonator dynamic response face severe challenges, and the application potential in the fields of ultra-high sensitivity sensing and basic physical research is severely restricted. SUMMARY

[0006] To solve the inherent bottlenecks of the traditional non-driven laser interference measurement method, the application innovatively introduces a precise polarization control system on the basis of the original Fabry-Perot interference optical path, realizes efficient transmission and utilization of laser energy, and makes the laser energy received by the photodetector theoretically 4 times that of the traditional laser interference system, greatly preserving the effective information.

[0007] The application adds a quarter wave plate and a half wave plate on the laser transmission path, adjusts the energy ratio of p-polarized light and s-polarized light of the input laser beam, and converts the original linearly polarized light and circularly polarized light into single p-polarized light and s-polarized light; the beam splitter in the traditional method is changed into a polarization beam splitter (PBS) for efficient light splitting, according to its core physical characteristics - nearly 100% reflection of s-polarized light and 100% transmission of p-polarized light, the polarization beam splitter realizes full transmission of incident light and full reflection of reflected light, so that the loss of laser energy on the transmission path is minimized, which is much lower than the minimum 75% (beam splitter splitting ratio 50:50) inherent splitting loss of the beam splitter.

[0008] The measured data show that, under the premise of keeping the same laser power, resonator and environmental conditions, the resonant peak voltage peak observed by the detector can be increased by more than 3 times; the displacement response of the micro-nano electromechanical resonator to be measured is increased by not less than 3 times, which means that small mechanical vibration can induce larger amplitude of electrical signal change, directly improving the detection capability and lower limit of range of the system; the displacement sensitivity is also greatly improved. The noise caused by the photodetector and the frequency analyzer accounts for 59% of the effective signal, effectively improving the signal-to-noise ratio, and the originally unclear resonant peak in the strong noise background can be clearly highlighted.

[0009] The beneficial effects of the application are that the application is based on polarization-optimized optical path enhancement technology, which maximizes the use of input laser energy and reduces the transmission loss of laser in the optical path. The weak response signal of the micro-nano electromechanical resonator in the non-driven thermal vibration state is substantially amplified and purified, providing a better measurement method for in-depth study of its dynamic characteristics. BRIEF DESCRIPTION OF DRAWINGS

[0010] Figure 1 is a schematic diagram of the polarization-enhanced micro-nano vibration laser interference dynamics measurement optimization method of embodiment 1;

[0011] Figure 2 is a sampling point diagram of the polarization-enhanced micro-nano vibration laser interference dynamics measurement optimization method of embodiment 2;

[0012] Figure 3 is the laser power at each sampling point of the polarization-enhanced micro-nano vibration laser interference dynamics measurement optimization method of embodiment 2 with different initial powers;

[0013] Figure 4 is a comparison chart of the response of the micro-nano electromechanical resonator with and without polarization enhancement of embodiment 3;

[0014] Figure 5 is a noise analysis chart in the interference measurement of embodiment 4.

[0015] List of reference numerals in the attached diagram:

[0016] 1-Laser generator, 2-1-First quarter glass slide, 2-2-Second quarter glass slide, 2-3-Third quarter glass slide, 3-Mirror, 4-Half glass slide, 5-Polarizing beam splitter cube mirror, 6-Objective lens, 7-Micro-nano electromechanical resonator, 8-Convex lens, 9-Photodetector, 10-Electrical signal to spectrum analyzer, 11-Network analyzer, 12-Blue laser generator, 13-Long-pass filter. Detailed Implementation

[0017] The technical solution of the present invention will now be described in detail with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0018] Example 1

[0019] like Figure 1 As shown, this invention provides an optimization method for micro / nano vibration laser interferometry dynamics measurement based on polarization enhancement. The method is based on a polarization control system and includes a laser generator 1, a reflector 3, a half-glass slide 4, a polarizing beam-splitting cubic mirror 5, an objective lens 6, a micro / nano electromechanical resonator 7, a convex lens 8, a photodetector 9, a spectrum analyzer 10, a network analyzer 11, a blue laser generator 12, and a long-pass filter 13. A first quarter-glass slide 2-1 is provided between the laser generator 1 and the reflector 3; a second quarter-glass slide 2-2 is provided between the reflector 3 and the half-glass slide 4; and a third quarter-glass slide 2-3 is provided between the polarizing beam-splitting cubic mirror 5 and the objective lens 6.

[0020] A laser beam of specific frequency and power is generated and output by laser generator 1. The generated laser is linearly polarized light. First, the angle of the fast axis of the first quarter-glass slide 2-1 is set to be 45° different from the direction of laser polarization. The incident linearly polarized light is converted into circularly polarized light after passing through 2-1. The circularly polarized light is more stable in the optical path. Due to the high transmittance of 2-1 (95%), the laser power is slightly reduced (the extinction ratio of 2-2 and 2-3 is the same as that of 2-1). The transmission direction of the laser is changed by the reflector 3. The angle of the fast axis of the second quarter-glass slide 2-2 is set to be the same as that of 2-1. At this time, the incident circularly polarized light is converted into linearly polarized light after passing through 2-2, so that the intensity ratio of the p-polarized and s-polarized states of the laser can be changed by half-glass slide 4. After the angle of the incident linearly polarized light is changed by half-glass slide 4 (transmittance > 95%), it is converted into sp-polarized light and reflected by the polarization beam splitter cube mirror 5. The polarization beam splitter cube mirror 5 has extremely high polarization for s-polarized light. The reflection extinction ratio (>1000:1) greatly reduces the transmission loss of the laser light after passing through a conventional beam splitter. The fast axis angle of the third quarter-glass slide 2-3 is set to be 45° different from that of the s-polarized light. The s-polarized light is converted into circularly polarized light after passing through the quarter-glass slide 2-3. It passes through the objective lens 6 and is focused onto the micro-nano electromechanical resonator 7 to generate an interference light field that returns to the multi-beam reflected beam. The reflected beam passes through the quarter-glass slide 2-3 again and is converted into linearly polarized light. At this time, the polarization state of the linearly polarized light is p-polarized light. The beam splitter cube mirror 5 has an extremely high transmission extinction ratio (>1000:1) for p-polarized light, which reduces the reflection loss after passing through the beam splitter. Finally, the reflected beam is focused by the convex lens 8 and hits the photodetector 9. The photodetector 9 converts the collected light signal into an electrical signal and transmits it to the spectrum analyzer 10 to draw the spectrum diagram.

[0021] In this embodiment, a polarization system is used to replace the ordinary beam splitter with a polarizing cubic beam splitter 5, which greatly reduces unnecessary laser power loss. Regardless of the transmittance of the ordinary beam splitter, the laser will pass through twice, and the maximum retained laser power intensity is 25% of the original. At this time, the transmittance of the beam splitter is 50:50. After changing to the polarizing cubic beam splitter 5, by controlling the polarization state of the polarized light, the laser power after passing through the polarizing cubic beam splitter a second time can be more than 75% of the initial power.

[0022] Micro-nano electromechanical resonators fabricated using different materials have very low non-driven mechanical thermal noise, making it difficult to observe resonance peaks on a spectrum analyzer using only red laser light. Therefore, an external drive is needed to make the resonator move more violently for easier observation. For example... Figure 1 The diagram shows the addition of photothermal and electrical drives to power the resonator.

[0023] To enhance the resonator's vibration using photothermal drive, the network analyzer 11 first outputs an AC signal, which, combined with a DC signal (Vg), controls the blue laser waveform generated by the blue laser generator 12. The generated blue laser is reflected by the long-pass filter 13 (reflects blue laser, transmits red laser), passes through the objective lens 6, and strikes the resonator 7. The resonator is then driven by laser heating. The reflected blue laser light passes through the long-pass filter 13 again and is emitted, but is not collected by the photodetector 9. At this point, the photodetector 9 is connected to the network analyzer 11 to analyze the resonator's spectrum.

[0024] To drive the resonator using electrical excitation, the network analyzer 11 outputs an AC signal and a DC signal Vg, which are then applied to the resonator's substrate. The negative piezoresistive effect converts electrical energy into mechanical energy, enhancing the resonator's vibration amplitude. Meanwhile, data measured by the red laser is transmitted to the network analyzer 11 via the photodetector 9 to observe the resonator's frequency spectrum.

[0025] Both photothermal and electrical drives utilize red lasers to measure the resonator, so the enhancement effect of this experiment is also applicable to both types of drives.

[0026] Example 2

[0027] like Figure 2 and 3 As shown, to demonstrate that the polarization system effectively enhances the effective optical signal of the laser, a comparison is made between a conventional laser interferometry system and a polarization-enhanced laser interferometry system. Assume the initial optical power of the conventional laser interferometry system is... The incident light is incident light 1, and the reflected light is reflected light 1; the initial optical power of the polarization-enhanced laser interferometry system is... The incident light is incident light 2, and the reflected light is reflected light 2; at this time .

[0028] Three points were selected in the optical path for sampling, such as... Figure 2 The numbers are marked in the optical path. Sampling point 1 is located at the position where circularly polarized light is converted to linearly polarized light, to observe the loss of laser power caused by the two added quarter-glass slides; sampling point 2 is located at the position where the input laser beam is first reflected by the polarizing beam splitter 5, to compare the change in laser power after passing through a regular beam splitter and a polarizing beam splitter 5; sampling point 3 is located in front of the photodetector 9 to verify the effect of the polarization system on laser power enhancement.

[0029] Sampling point 1:

[0030] Incident light 1 passes through mirror 3 (reflectivity is...) Optical power: ;

[0031] Incident light 2 passes through a quarter-glass slide 2-1 (transmittance is...) ), 3 mirrors, 2-2 quarter-glass slides (transmittance is 100%) Optical power: ;

[0032] Sampling point 2:

[0033] Incident light 1 is reflected by a conventional beam splitter (transmittance is 100%) The reflectivity is Optical power: ;

[0034] Incident light 2 passes through half-glass plate 4 (transmittance is 4%) ), polarizing beam splitter cube mirror 5 (p-polarized light transmittance is 50 ... The reflectance of s-polarized light is Optical power: ;

[0035] Sampling point 3:

[0036] Incident light 1, after passing through objective lens 6 and striking the device, forms multiple reflected beams 1. Because the device is not a smooth mirror, a certain amount of loss occurs, approximately a fixed percentage (A). After further reflection by a standard beam splitter, the optical power is: ;

[0037] Incident light 2 passes through a quarter-glass slide 23 (transmittance is...) After objective lens 6 hits the device, it forms multiple reflected beams 2. The reflected beams 2 pass through a quarter-glass slide 23 and a transmission polarizing beam-splitting cubic mirror. The optical power is: ;

[0038] Finally, the optical power reaching the photodetector in the traditional laser interferometry system is:

[0039]

[0040] The optical power reaching the photodetector in the polarization-enhanced laser interferometry system is:

[0041]

[0042] The ratio between the two is:

[0043]

[0044] The increased intensity of the polarization system will be determined by the increased slide transmittance, the transmittance of the polarizing beam splitter, and the splitting ratio of a conventional beam splitter in a traditional system. Substituting the mirror parameters into these parameters yields: , ;at this time After adding polarization, the optical power received by the photodetector increased by 2.01 times. This value was obtained based on the minimum transmittance of the actual quarter-wave plate, half-wave plate, and polarizing beam splitter, as well as the minimum reflectance of the reflector and polarizing beam splitter.

[0045] If we consider the transmittance and reflectance of the mirror, quarter-wave plate, half-wave plate, and polarizing beam-splitting cubic mirror under ideal conditions:

[0046] Sampling point 1:

[0047] Incident light 1 passes through mirror 3, optical power: ;

[0048] Incident light 2 passes through quarter-glass slide 21, mirror 3, and quarter-glass slide 22. Optical power: ;

[0049] Sampling point 2:

[0050] Incident light 1 is reflected by a conventional beam splitter (transmittance is 100%) The reflectivity is Optical power: ;

[0051] Incident light 2 passes through half-glass plate 4 and polarizing beam splitter 5, optical power: Sampling point 3:

[0052] Incident light 1, after passing through objective lens 6 and hitting the device, forms multiple reflected beams 1. Because the device is not a smooth mirror, a certain loss occurs, approximately a fixed A (percentage) loss. After passing through a conventional beam splitter, the optical power is: ;

[0053] Incident light 2, after passing through quarter-glass slide 23 and objective lens 6, strikes the device and forms multiple reflected beams 2. These reflected beams 2 are then reflected by quarter-glass slide 23 and polarizing beam-splitting cubic mirror. Optical power:

[0054] Finally, the optical power reaching the photodetector in the traditional laser interferometry system is:

[0055]

[0056] The optical power reaching the photodetector in the polarization-enhanced laser interferometry system is:

[0057]

[0058] The ratio between the two is:

[0059]

[0060] The increased intensity of the polarization system will be determined by the splitting ratio of a conventional beam splitter. Substituting the mirror's parameters into this equation yields: , ;at this time The increased polarization resulted in a 3-fold increase in the optical power received by the photodetector.

[0061] Theoretical calculations show that by adding a polarization enhancement system, the optical power received by the photodetector in a traditional laser interferometry system will be increased by 2 times, but not more than 3 times.

[0062] To further verify the reliability of the theory, a comparison was made between a traditional laser interferometry system and a polarization-enhanced laser interferometry system by varying the initial laser power. The initial laser power was set starting at 12 mW and decreasing by 2 dB, with six initial laser powers selected: 12 mW, 7.57 mW, 4.78 mW, 3.01 mW, 1.9 mW, and 1.2 mW. Figure 3 The changes between the two systems are clearly visible. At sampling point 1, the addition of two quarter-slides inevitably leads to a loss of laser power, resulting in a slightly lower laser power in the polarization system compared to the original system. At sampling point 2, the laser power in the polarization system is approximately twice that of the original system. At sampling point 3, the laser power in the polarization system is more than three times that of the original system. Considering the losses incurred by the laser as it passes through the objective lens and strikes the micro / nano electromechanical resonator, the increase in laser power at this point is already quite significant.

[0063] Example 3

[0064] like Figure 4 As shown, in order to verify that the laser signal enhanced by the polarization system has a more than 3-fold improvement in the detection of micro-nano electromechanical resonators, the parameters of the SiN square resonator were analyzed using the obtained laser signal based on the system of Example 2. The responsivity of each system was compared in detail, and further comparative experiments were carried out by changing the initial laser power.

[0065] Voltage domain measurements are converted into displacement domain information to obtain details of device motion and measurement sensitivity. To correlate the signal measured in the voltage domain with the device's mechanical displacement, a method is employed... This describes the functional relationship between the thermomechanical noise displacement spectral density of a resonator in the displacement domain and the angular frequency ω. Angular resonant frequency in m-mode; Boltzmann constant; Absolute temperature; Quality factors; The effective mass of the device. At the resonant frequency, the functional relationship between the thermomechanical displacement noise displacement spectral density of the resonator in the displacement domain and the angular frequency ω can be simplified to: The voltage spectral density of thermomechanical shift noise of the resonator in the voltage domain can be obtained from the spectrum plot obtained by the spectrum analyzer. ,in This is the total voltage noise spectral density, the maximum value in the voltage spectral density plot. It is the electronic noise floor of the measurement system, and the average value of the relatively smooth straight lines on both sides of the peak in the voltage spectral density plot.

[0066] To correlate the electric resonator in the voltage and displacement domains, a responsivity is used. Quantization is performed; displacement domain noise spectral density is utilized. and responsiveness The sensitivity of the displacement can be obtained:

[0067]

[0068] Multiple SiN square micro / nano electromechanical resonators were tested using different initial powers: 12mW, 7.57mW, 4.78mW, and 3.01mW. , and The values ​​are compared. In the initial power used in this example, the polarization-enhanced laser measurement system... and Compared to traditional laser measurement systems, it has achieved more than 3 times the improvement, from Figure 4 The results clearly show the responsivity of the polarization enhancement system compared to traditional laser interferometry at different initial frequencies. It increased by more than three times.

[0069] Further analysis of displacement sensitivity Analysis revealed that, with an initial power of 12mW and other conditions remaining constant, the displacement sensitivity value increased from 89.60 fm / Hz after adding the polarization enhancement system. -1 / 2 Reduced to 44.38 fm / Hz -1 / 2 The improvement reached 101.9%, which solved the core bottleneck of insufficient sensitivity in high-order modality detection, transforming the search for high-order modalities from a technical challenge into a feasible and efficient solution.

[0070] Example 4

[0071] like Figure 5 As shown, the data from Example 3 are used again; the signal-to-noise ratio is significantly improved due to the increased displacement sensitivity. The same SiN square micro / nano electromechanical resonator is compared between a polarization-enhanced laser interferometry system and a conventional laser interferometry system at an initial power of 12mW to analyze their respective noise contributions.

[0072] Total Voltage Noise Spectral Density It is caused by 1) thermomechanical noise At this point, the required signal is present; 2) Spectrum analyzer noise. 3) Photodetector noise and 4) Laser noise Composition. From Figure 5 The diagram shows the noise analysis details in interferometry. The left diagram is the noise analysis diagram of a traditional laser interferometry system, and the right diagram is the noise analysis diagram of a polarization-enhanced laser interferometry system. The blue line represents the noise generated by the spectrum analyzer, the red line represents the noise generated by the spectrum analyzer and photodetector, and the black line represents the thermomechanical noise.

[0073] This section primarily analyzes the noise of the spectrum analyzer. and photodetector noise Electronic noise of the measurement system The proportion. From Figure 5 The left figure shows the proportion of noise in the spectrum analyzer under the traditional system: The noise ratios of the spectrum analyzer and photodetector are as follows: The right figure shows the proportion of noise in the spectrum analyzer under the polarization enhancement system: The noise ratios of the spectrum analyzer and photodetector are as follows: The inherent noise of the equipment was reduced from 80.46% to 59.17%, effectively improving the signal-to-noise ratio of the system.

[0074] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the technical solutions of the embodiments of the present invention.

Claims

1. An optimization method for micro / nano vibration laser interferometry dynamics measurement based on polarization enhancement, characterized in that, The polarization control system includes a laser generator (1), a mirror (3), a half-glass plate (4), a polarization beam splitter (5), an objective lens (6), a micro-nano electromechanical resonator (7), a convex lens (8), a photodetector (9), a spectrum analyzer (10), a network analyzer (11), a blue laser generator (12), and a long-pass filter (13). A first quarter-glass plate (2-1) is provided between the laser generator (1) and the mirror (3), a second quarter-glass plate (2-2) is provided between the mirror (3) and the half-glass plate (4), and a third quarter-glass plate (2-3) is provided between the polarization beam splitter (5) and the objective lens (6).

2. The method for optimizing micro / nano vibration laser interferometry dynamics measurement based on polarization enhancement according to claim 1, characterized in that, The laser generator (1) generates and outputs a laser beam of a specific frequency and power. The laser beam generated at this time is linearly polarized light. The incident linearly polarized light is converted into circularly polarized light after passing through the first quarter glass plate (2-1). The direction of laser propagation is changed by the reflector (3). At this time, the incident circularly polarized light is converted into linearly polarized light after passing through the second quarter glass plate (2-2). The intensity ratio of the p-polarized state and s-polarized state of the laser is changed by the half glass plate (4). The angle of the incident linearly polarized light is changed by the half glass plate (4) and converted into sp-polarized light, which is reflected by the polarization beam splitter (5). The s-polarized light is converted into circularly polarized light through the third quarter glass plate (2-3), passes through the objective lens (6) and is focused onto the micro-nano electromechanical resonator (7) to generate an interference light field that returns to multiple reflected beams; the reflected beam passes through the third quarter glass plate (2-3) again and is converted into linearly polarized light, at which point the polarization state of the linearly polarized light is p-polarized light; finally, the reflected beam is focused by the convex lens (8) and hits the photodetector (9), which converts the collected light signal into an electrical signal and transmits it to the spectrum analyzer (10) to draw the spectrum diagram.

3. The method for optimizing micro / nano vibration laser interferometry dynamics measurement based on polarization enhancement according to claim 1, characterized in that, The fast axis angle of the first quarter-glass slide (2-1) is set to be 45° different from the direction of laser polarization. The fast axis angle of the second quarter-glass slide (2-2) is the same as that of the first quarter-glass slide (2-1). The fast axis angle of the third quarter-glass slide (2-3) is set to be 45° different from that of s-polarized light.

4. The method for optimizing micro / nano vibration laser interferometry dynamics measurement based on polarization enhancement according to claim 1, characterized in that, The extinction ratios of the first quarter slide (2-1), the second quarter slide (2-2), and the third quarter slide (2-3) are the same.

5. The method for optimizing micro / nano vibration laser interferometry dynamics measurement based on polarization enhancement according to claim 1, characterized in that, The transmittance of the half-glass slide (4) is >95%.

6. The method for optimizing micro / nano vibration laser interferometry dynamics measurement based on polarization enhancement according to claim 1, characterized in that, The beam-splitting cubic mirror (5) has a reflection extinction ratio of >1000:1 for s-polarized light and a transmission extinction ratio of >1000:1 for p-polarized light.

7. The method for optimizing micro / nano vibration laser interferometry dynamics measurement based on polarization enhancement according to claim 1, characterized in that, To enhance the vibration of the resonator using photothermal drive, the network analyzer (11) outputs an AC signal, which is then combined with a DC signal of Vg to control the blue laser waveform generated by the blue laser generator (12). The generated blue laser is reflected by a long-pass filter (13), where the blue laser is reflected and the red laser is transmitted. The blue laser is then hit onto the resonator (7) through the objective lens (6), and the resonator is driven by laser heating. After being reflected, the blue laser will be reflected again by the long-pass filter (13) and will not be collected by the photodetector (9). At this time, the photodetector (9) is connected to the network analyzer (11) to analyze the spectrum of the resonator.

8. The method for optimizing micro / nano vibration laser interferometry dynamics measurement based on polarization enhancement according to claim 7, characterized in that, The resonator is driven by electrical excitation. The AC signal and DC signal of Vg output by the network analyzer (11) are applied to the substrate of the resonator. The negative piezoresistive effect is used to convert electrical energy into mechanical energy of the resonator, thereby enhancing the vibration amplitude of the resonator. At this time, the data obtained by the red laser measurement is transmitted to the network analyzer (11) via the photodetector (9) to observe the spectrum of the resonator.

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