CN209911228U - Structure target for improving speed stability of laser loading shock wave - Google Patents
Structure target for improving speed stability of laser loading shock wave Download PDFInfo
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Abstract
The utility model relates to a promote structure target of laser loading shock wave velocity stability belongs to material high pressure characteristic technical field, including ablation layer, barrier layer and sample layer, ablation layer sets up towards the diagnosis hole, and the barrier layer is located ablation layer top for shielding preheating of high energy photon and electron, the barrier layer includes Au rete and the wall that the interval set up, the material of wall is the same with the material of ablation layer, and the sample layer is located the barrier layer top, and is equipped with the stratum basale between sample layer and the barrier layer, the utility model discloses set up Au rete and wall interval in order to form the barrier layer, the shock wave makes a round trip to reflect the speed change that rapid smooth Au rete brought in the barrier layer, can reach the purpose of realizing stable shock wave output, can compromise the requirement to preheating shielding again, is applicable to and contains multiple laser loading modes such as laser direct drive and black chamber indirect drive, has wider applicability.
Description
Technical Field
The utility model belongs to the technical field of the material high pressure characteristic, specifically speaking relates to a promote structure target of laser loading shock wave velocity stability.
Background
In the field of material high-pressure loading research, a laser loading shock wave experimental platform is an important loading mode, and has the advantages that a high-power laser device can be used for generating extremely high pressure in a sample, so that the parameter interval of research is expanded. Particularly, the laser platform has unique loading advantages in a range of hundreds of GPa pressure. On the other hand, however, the high-energy X-rays (hard X-rays) and high-energy electrons generated during laser ablation of the sample can heat the sample in advance, which is disadvantageous for the measurement of the compressive state of the material because the energy deposition of the high-energy photons and electrons changes the initial state of the material to an unknown state. Therefore, in order to obtain high quality reliable experimental data, we need to effectively control the high energy photon and electron preheating on the laser platform.
In experiments, the method is usually realized by adding a high-Z barrier layer in a sample, and the characteristic that the high-Z barrier layer has strong absorption to high-energy photons and electrons is utilized for shielding. Fig. 1 shows the structural design of a target used in a conventional laser loading platform, wherein a medium-low Z ablation layer is arranged on one side close to a driving source, a high-Z shielding layer is arranged in the middle, and a sample layer to be loaded is arranged on the other side. The design can effectively reduce the preheating influence, but another problem is caused at the same time, that is, the stability of the shock wave is poor, the main reason is that the impedance of the high-Z barrier layer is often greatly different from the materials on two sides, so that the intensity of the shock wave can be greatly attenuated when the shock wave is transmitted to the interface position of the barrier layer, meanwhile, the interface has strong reflection and sparse processes, and then the shock wave can be remarkably pursued after entering the to-be-loaded sample layer, and the transmission stability of the shock wave is damaged. The stability of the shock wave is important for physical research, for example, in a physical equation experiment, the uncertainty of a measured value can be reduced by the stable shock wave speed, so that the precision and the reliability of experimental data of the physical equation are improved. In the phase change research of materials, a stable shock wave is often required to generate a uniform initial state in a sample, and then accurate phase change state and parameter point position information are obtained.
Based on the specific requirements, the improvement of the stability of the laser loading shock wave has important significance. At present, the stability of the loading shock wave is attempted to be improved mainly by two means abroad: firstly, the wave form of adjustment drive pulse and the intensity evolution of driving source to compensate shock wave loss and the intensity decay in transmission process, the difficult point of this technique lies in, at first need realize the accurate control to the laser wave form, has very high requirement to experiment controllability, and the high Z material barrier layer can make the shock wave transmission action become difficult to predict in the target sample of laser experiment, only hardly plays optimization and modified effect to shock wave stability through adjusting the laser wave form this moment. The second is achieved by reducing the thickness of the barrier layer, which enables the wave system to quickly reach equilibrium by back-and-forth reflection therein, but this increases the risk of insufficient preheating shielding.
SUMMERY OF THE UTILITY MODEL
In order to solve the above problems, a structural target for improving the speed stability of laser loaded shock wave is proposed to improve the speed stability of laser loaded shock wave and to be compatible with the problem of preheating shielding in the structural target.
In order to achieve the above object, the utility model provides a following technical scheme:
a structural target for enhancing laser loaded shock wave velocity stability, comprising:
an ablation layer, which is arranged facing the diagnostic hole and which forms an ablation pressure under the action of the laser;
the barrier layer is positioned above the ablation layer and used for shielding the preheating of high-energy photons and electrons, the barrier layer comprises an Au film layer and a spacer layer which are arranged at intervals, and the material of the spacer layer is the same as that of the ablation layer;
and the sample layer is positioned above the barrier layer, and a substrate layer is arranged between the sample layer and the barrier layer.
Further, the target surface center of the structural target coincides with the center of the diagnostic hole, and the width-to-thickness ratio of the structural target is greater than 2.
Further, the lengths of the barrier layer and the sample layer are equal to the length of the ablation layer, and the widths of the barrier layer and the sample layer are equal to the width of the ablation layer.
Further, the length of the diagnosis hole along the cavity axis direction of the driving black cavity is a0With a width of b0And a is a0>b0The length of the ablation layer is a1With a width of b1Then a is1≥a0+200μm，b1≥b0+200μm。
Further, the drive black cavity is made of Au and is of a straight-tube structure with an upper opening and a lower opening, disc-shaped shielding sheets are arranged on the periphery of the drive black cavity and 100 micrometers away from the upper opening and the lower opening of the drive black cavity, the shielding sheets are made of Cu, and a CH layer is coated on the surfaces of the shielding sheets.
Further, the ablation layer is made of a medium-low Z plane material, and the medium-low Z plane material includes but is not limited to CH, Al and Cu.
Further, when the medium-low Z plane material is Al, the thickness of the ablation layer is 35-60 μm, and when the medium-low Z plane material is Cu, the thickness of the ablation layer is 25-40 μm.
Further, when the radiation temperature of the driving black cavity is lower than 140eV, the total thickness of the Au film layer is 3 μm, the thickness of the single-layer Au film layer is 0.3 μm, the total thickness of the Au film layer is 10 layers, and the thickness of the spacer layer is 1 μm.
Further, when the irradiation temperature of the driving black cavity is set to 140eV, the hard X-ray fraction is set to M1% absorption coefficient u of Au film layer1The total thickness of the Au film layer is 3 μm, and the irradiation temperature when driving the black cavity is T2And T is2>At 140eV, the hard X-ray fraction is M2% of Au film layer absorption coefficient is u2Total thickness of Au film layer is t2Then, then
Further, the material of the base layer includes but is not limited to Al, Cu, quartz, polypropylene, and H > D × t, wherein H represents the thickness of the base layer, D represents the transmission speed of the shock wave, and t represents the main laser action time.
The utility model has the advantages that:
the Au film layer and the spacing layer are arranged at intervals to form the blocking layer, shock waves are reflected back and forth in the blocking layer to quickly smooth speed changes brought by the Au film layer, the purpose of stabilizing shock wave output can be achieved, the requirements on preheating shielding can be met, the laser loading device is suitable for various laser loading modes including laser direct driving, black cavity indirect driving and the like, and the laser loading device has wide applicability.
Drawings
FIG. 1 is a schematic diagram of a target structure used on a prior art laser loading platform;
fig. 2 is a schematic view of the overall structure of the present invention;
FIG. 3 is a schematic view of the structure of a barrier layer;
FIG. 4 is a schematic diagram of the structure of the driving black cavity;
FIG. 5 is a schematic diagram showing the historical evolution of the velocity of shock waves in the Al-based sample layer in the second embodiment;
FIG. 6 is a schematic diagram showing the historical evolution of the velocity of shock waves in the Al substrate sample layer in the third embodiment;
FIG. 7 is a schematic diagram showing the historical evolution of the velocity of shock waves in the Al substrate sample layer in the fourth embodiment;
FIG. 8 is a schematic diagram showing the historical evolution of the velocity of the shock wave in the Cu substrate sample layer in the fifth embodiment.
In the drawings: 1-ablation layer, 2-barrier layer, 201-Au film layer, 202-spacing layer, 3-sample layer, 4-driving black cavity, 5-laser injection port I, 6-laser injection port II, 7-shielding sheet and 8-diagnosis hole;
in fig. 5 to 8, the abscissa represents time in ns, and the ordinate represents the velocity of the shock wave in km/s.
Detailed Description
In order to make those skilled in the art better understand the technical solution of the present invention, the following description, together with the drawings of the present invention, clearly and completely describes the technical solution of the present invention, and based on the embodiments in the present application, other similar embodiments obtained by those skilled in the art without creative efforts shall all belong to the protection scope of the present application. In addition, directional terms such as "upper", "lower", "left", "right", etc. in the following embodiments are directions with reference to the drawings only, and thus, the directional terms are used for illustration and not for limitation of the present invention.
The first embodiment is as follows:
as shown in fig. 2-4, a structural target for improving the speed stability of laser-loaded shock waves is located at a diagnosis hole 8 of a driving black cavity 4, specifically, the driving black cavity 4 is made of Au and has a straight-tube structure with upper and lower openings, the upper and lower openings are respectively used as a laser injection port i 5 and a laser injection port ii 6, laser enters the driving black cavity 4 through the laser injection port i 5 and the laser injection port ii 6 to generate a uniform high-temperature X-ray radiation field, disc-shaped shielding sheets 7 are arranged on the periphery of the driving black cavity 4 and 100 μm away from the upper and lower openings of the driving black cavity to shield stray light, the shielding sheets 7 are made of Cu, and the surfaces of the shielding sheets 7 are coated with CH layers. The diagnosis hole 8 is positioned on the side wall of the driving black cavity 4, the structural target is placed on the diagnosis hole 8, and meanwhile, the center of the target surface of the structural target is superposed with the center of the diagnosis hole 8.
Specifically, the structured target includes an ablation layer 1, a barrier layer 2, and a sample layer 3. Wherein the ablation layer 1 is arranged facing the diagnostic opening 8, which ablation pressure is created by the laser. The barrier layer 2 is located above the ablation layer 1 and used for shielding preheating of high-energy photons and electrons, meanwhile, the barrier layer 2 comprises an Au film layer 201 and a spacer layer 202 which are arranged at intervals, the material of the spacer layer 202 is the same as that of the ablation layer 1, so that impedance among different layers is guaranteed to be consistent, and shock wave speed change caused by rapid and smooth high-Z materials in the back-and-forth reflection process of shock waves can be achieved due to the fact that the Au film layer 201 and the spacer layer 202 are arranged at intervals, and the purpose of achieving stable shock wave output is achieved. The sample layer 3 is located above the barrier layer 2, and a base layer is arranged between the sample layer 3 and the barrier layer 2. The sample layer 3 may have different geometric structures according to specific research objects, such as an impedance matching structure for relative measurement of a state equation, a sandwich structure for multi-impact loading, and the like, and similarly, based on understanding of compression characteristics of materials such as Al and Cu, materials such as Al and Cu are often adopted as substrates in different geometric structure designs of the sample layer 3. Meanwhile, quartz (SiO2) and transparent materials such as Polypropylene (PS) are also candidates for the substrate, and quartz and polypropylene have the advantage that the quartz and polypropylene are transparent to visible light and can be used for observing complete shock wave transmission behaviors. That is, the material of the substrate layer includes, but is not limited to, Al, Cu, quartz, polypropylene.
Given the sparse transmission at the sides and the size constraints of the diagnostic aperture 8, the flat area of the shock wavefront shrinks over time, i.e. the greater the thickness, the smaller the final usable planar area, and therefore the utility model design requires a structural target aspect ratio of greater than 2. Meanwhile, the utility model discloses the problem of chasing after of sparse wave or shock wave is considered to the people, when there is sparse wave to chase after in a certain region, in case sparse wave chases after loaded shock wave, will lead to loading pressure inhomogeneous. In view of the above influencing factors, utility model people combine hydrodynamic procedures to make the following preferences for the size of the structured target:
the lateral dimension (length) of the effective loading area of the ablation layer 1 determines the size of the experimental measurement area, which is mainly determined by the planarity of the loading source, such as the focal spot size after smoothing of the laser beam or the driving black cavity diagnostic hole opening size. The length of the diagnosis hole 8 along the cavity axis direction of the driving black cavity 4 is a0With a width of b0And a is a0>b0The length of the ablation layer 1 is a1With a width of b1Then a is1≥a0+200μm，b1≥b0+200 μm, and a0Typically between 500 μm and 1000 μm. The lengths of the barrier layer 2 and the sample layer 3 are equal to the length of the ablation layer 1, and the widths of the barrier layer 2 and the sample layer 3 are equal to the width of the ablation layer 1. The ablation layer 1 is made of a medium-low Z plane material, and the medium-low Z plane material includes but is not limited to CH, Al and Cu. The medium and low Z plane material has the commonality that higher ablation pressure can be formed under the action of laser, meanwhile, the physical properties of the medium and low Z plane material under high pressure are sufficiently researched in experiments, different loading pressures can be accurately and efficiently obtained by changing the strength of a driving source and used for quantitative loading design, and thus different experimental purposes are realized. When the medium-low Z plane material is Al, the thickness of the ablation layer 1 is 35-60 μm, and when the medium-low Z plane material is Cu, the thickness of the ablation layer 1 is 25-40 μm.
The total thickness of the Au film layer 201 is determined by the flux of energetic photons and electrons it needs to shield, and its flux can be characterized by the intensity of the loaded source. According to the experimental measurement result, when the radiation temperature of the driving black cavity 4 is lower than 140eV, high-energy photons and electrons can be effectively shielded by the Au film layer 201 with the thickness of 3 μm, and the same is achievedIn this case, the Au film layer 201 is 10 layers, each Au film layer 201 has a thickness of 0.3 μm, and the spacer layer 202 has a thickness of 1 μm. Setting the radiation temperature of the driving black cavity as 140eV, the hard X-ray share is M1% absorption coefficient u of Au film layer1The total thickness of the Au film layer is 3 μm, and the irradiation temperature when driving the black cavity is T2And T is2>At 140eV, the hard X-ray fraction is M2% of Au film layer absorption coefficient is u2Total thickness of Au film layer is t2Then, then
The thickness of the base layer is required to ensure that the reflected shock wave cannot catch up with the transmitted shock wave, i.e. the thickness of the base layer is mainly determined by the transmission speed of the shock wave and the catch-up ratio of the shock wave, so that the shock wave can be sufficiently accelerated before entering the barrier layer 2. And H > D t, wherein H represents the thickness of the substrate layer, D represents the shock wave transmission speed, and t represents the main laser action time.
Example two:
parts of this embodiment that are the same as those of the first embodiment are not described again, except that:
in order to create a uniform radiation field environment, the length-width ratio of the driving black cavity 4 is optimized to be 2:1, the length is 2400 μm, the inner diameter is 1200 μm, the wall thickness is 35 μm, the diameters of the laser injection port I5 and the laser injection port II 6 are 850 μm, the length of the diagnosis hole 8 along the cavity axis direction is 700 μm, and the width along the vertical cavity axis direction is 400 μm. The structural target is a square with the side length of 900 mu m, the structure is an Al ablation layer/an Al-Au barrier layer/an Al substrate sample layer (the Al ablation layer represents that the ablation layer is made of Al, the Al-Au barrier layer represents that the spacing layer is made of Al, and the Al substrate sample layer represents that the substrate layer is made of Al), and the thicknesses of the Al ablation layer/the Al-Au barrier layer are respectively 40/(1+0.3) multiplied by 10 mu m. The stability of the shock wave transmission after entering the Al base sample layer was evaluated in the calculation.
The laser wavelength was 0.351 μm, the total input energy was 800J, and the power density was 5X 1013W/cm2The pulse width is 1 ns. The laser is 8 beams, and 4 beams are used as a group to respectively obtain the laser beamsThe injection port I5 and the laser injection port II 6 are incident. The included angle between the central direction of the laser beam and the axial direction of the black cavity is 45 degrees, and the radiation temperature for driving the black cavity is about 120 eV.
The Al ablation layer faces the drive source and its lateral dimension (length) is mainly determined by the size of the sample platform (900 μm) where the black cavity diagnostic hole is driven and has a thickness of 40 μm. The laser or X-ray deposits energy by ablating the Al ablation layer, creating a high pressure shock wave therein. The lateral dimensions of each of the Al-Au barrier layers are consistent with the Al ablation layer. The Au film layers are 10 layers in total, the thickness of each Au film layer is 0.3 mu m, and the thickness of the spacing layer is 1 mu m.
Quantitative evaluation is performed on the embodiment by adopting a fluid mechanics simulation program, the velocity evolution of the shock wave in the Al substrate sample layer is directly calculated, and the history of the shock wave velocity in the Al substrate sample layer is shown in FIG. 5. In order to compare and simultaneously give the history of the shock wave velocity in the conventional Al ablation layer/Au barrier layer/Al substrate sample layer target design, wherein the thickness of the Al ablation layer is 40 μm, the thickness of the Au barrier layer is 3 μm, the Al substrate sample layer is made of Al, and FIG. 5 simultaneously gives the velocity change in the Al substrate sample layer under the conventional target design obtained by using the hydrodynamics simulation. The solid line in the figure represents the shock wave velocity history obtained with the target of the present embodiment configuration; the dashed line represents the shock wave velocity history obtained for a conventional target structure. From the results, it can be seen that after the shock wave is transmitted into the sample layer, the shock wave under the structure of the conventional target has an obvious chasing phenomenon in the Al-based sample layer, which results in a significant acceleration process of the shock wave and reduces the stability of transmission, while the speed stability of the shock wave in the Al-based sample layer obtained by using the structural target of the present embodiment is better, and the relative deviation is controlled to be about 3%, which is much lower than 13% of that of the conventional target. Therefore, utilize this embodiment structure target can obtain more stable shock wave speed in the Al base sample layer, explain the utility model discloses can be used for promoting the velocity stability of shock wave well.
Example three:
parts of this embodiment that are the same as the embodiment are not described again, except that:
the wavelength of the incident laser was 0.351 μm, the total input energy was 1600J, and the power density was 1×1014W/cm2The pulse width is 1ns, and the radiation temperature for driving the black cavity is about 140 eV.
Quantitative evaluation is performed on the embodiment by adopting a fluid mechanics simulation program, the velocity evolution of the shock wave in the Al substrate sample layer is directly calculated, and the history of the shock wave velocity in the Al substrate sample layer is shown in FIG. 6. In order to compare and simultaneously give the history of the shock wave velocity in the conventional Al ablation layer/Au barrier layer/Al substrate sample layer target design, wherein the thickness of the Al ablation layer is 40 μm, the thickness of the Au barrier layer is 3 μm, the Al substrate sample layer is made of Al, and FIG. 6 simultaneously gives the velocity change in the Al substrate sample layer under the conventional target design obtained by using the hydrodynamics simulation. The solid line in the figure represents the shock wave velocity history obtained with the target of the present embodiment configuration; the dashed line represents the shock wave velocity history obtained for a conventional target structure. From the results, it can be seen that after the shock wave is transmitted into the sample layer, the shock wave under the conventional target structure has a significant phenomenon of chasing, the speed is rapidly increased from 18km/s initially to 23km/s, and then slowly decreased, the significant acceleration process of the shock wave occurs, which reduces the stability of transmission, while the stability of the shock wave speed in the Al-based sample layer obtained by using the structural target of the present embodiment is better, and the variation range is far lower than that of the conventional target type. Therefore, utilize this embodiment structure target can obtain more stable shock wave speed in the Al base sample layer, explain the utility model discloses can be used for promoting the velocity stability of shock wave well.
Example four:
parts of this embodiment that are the same as the embodiment are not described again, except that:
the structural target is a Cu ablation layer/a Cu-Au barrier layer/an Al substrate sample layer, and the degrees of the Cu ablation layer/the Cu-Au barrier layer are respectively 25/(1+0.3) multiplied by 10 mu m. The stability of the shock wave transmission after entering the Al base sample layer was evaluated in the calculation. The laser wavelength was 0.351 μm, the total input energy was 1600J, and the power density was 1X 1014W/cm2The pulse width is 1ns, and the radiation temperature for driving the black cavity is about 140 eV.
Quantitative evaluation is performed on the embodiment by adopting a fluid mechanics simulation program, the velocity evolution of the shock wave in the Al substrate sample layer is directly calculated, and the history of the shock wave velocity in the Al substrate sample layer is shown in FIG. 7. For comparison, the history of the shock wave velocity in the conventional target design of the Cu ablation layer/Au barrier layer/Al substrate sample layer is given, wherein the thickness of the Cu ablation layer is 25 μm, the thickness of the Au barrier layer is 3 μm, the Al substrate sample layer is made of Al, and FIG. 7 also shows the velocity change in the Al substrate sample layer obtained by the conventional target design using hydrodynamic simulation. The solid line in the figure represents the shock wave velocity history obtained with the target of the present embodiment configuration; the dashed line represents the shock wave velocity history obtained for a conventional target structure. From the results, it can be seen that after the shock wave is transmitted into the Al-based sample layer, the shock wave under the conventional target structure has an obvious chasing phenomenon, which results in a significant acceleration process of the shock wave, and reduces the stability of transmission, while the speed stability of the shock wave in the Al-based sample layer obtained by using the structural target of the present embodiment is better, and the relative change is controlled at about 5%, which is far lower than 40% of that of the conventional target type. Therefore, utilize this embodiment structure target can obtain more stable shock wave speed in the Al base sample layer, explain the utility model discloses can be used for promoting the velocity stability of shock wave well.
Example five:
parts of this embodiment that are the same as the embodiment are not described again, except that:
the structural target is a Cu ablation layer/a Cu-Au barrier layer/a Cu substrate sample layer, namely, the ablation layer, the spacing layer and the substrate layer are all made of Cu, the thicknesses of the Cu ablation layer/the Cu-Au barrier layer are respectively 25/(1+ 0.3). times.10 mu m, the thickness of the spacing layer is 1 mu m, and the shock wave transmission stability after entering the Cu substrate sample layer is evaluated in calculation. The laser wavelength was 0.351 μm, the total input energy was 1600J, and the power density was 1X 1014W/cm2The pulse width is 1ns, and the radiation temperature for driving the black cavity is about 140 eV.
Quantitative evaluation is performed on the embodiment by adopting a fluid mechanics simulation program, the velocity evolution of the shock wave in the Cu substrate sample layer is directly calculated, and the velocity history of the shock wave in the Cu substrate sample layer is shown in FIG. 8. For comparison, the history of the shock wave velocity in the conventional Cu ablation layer/Au barrier layer/Cu substrate sample layer target design is given, wherein the thickness of the Cu ablation layer is 25 μm, the thickness of the Au barrier layer is 3 μm, and the substrate sample layer is made of Cu. Fig. 8 also shows the velocity change in the Cu base sample layer obtained with the conventional target design using hydrodynamic simulations. The solid line in the figure represents the shock wave velocity history obtained with the target of the present embodiment configuration; the dashed line represents the shock wave velocity history obtained with a conventional target structure. It can be seen from the results that after the shock wave is transmitted into the sample layer, the shock wave under the conventional target structure has an obvious catch-up phenomenon in the Cu-based sample layer, which results in a significant acceleration process of the shock wave and reduces the transmission stability, while the shock wave velocity stability in the Cu-based sample layer obtained by using the structural target of the present embodiment is better. Therefore, utilize this embodiment structure target can obtain more stable shock wave speed in the Cu basement sample layer, explain the utility model discloses can be used for promoting the speed stability of shock wave well.
The above description is only a preferred embodiment of the present invention, and should not be taken as limiting the scope of the invention, i.e. the present invention is intended to cover all equivalent variations and modifications within the scope of the present invention.
Claims (10)
1. A structural target for enhancing laser loaded shock wave velocity stability at a diagnostic aperture driving a black cavity, comprising:
an ablation layer, which is arranged facing the diagnostic hole and which forms an ablation pressure under the action of the laser;
the barrier layer is positioned above the ablation layer and used for shielding the preheating of high-energy photons and electrons, the barrier layer comprises an Au film layer and a spacer layer which are arranged at intervals, and the material of the spacer layer is the same as that of the ablation layer;
and the sample layer is positioned above the barrier layer, and a substrate layer is arranged between the sample layer and the barrier layer.
2. The structural target of claim 1, wherein the target face center of the structural target coincides with the center of the diagnostic aperture and the structural target has an aspect ratio greater than 2.
3. The structural target of claim 2 wherein the barrier layer, sample layer, and ablation layer have a length equal to the length of the ablation layer and a width equal to the width of the barrier layer, sample layer, and ablation layer.
4. The structural target of claim 3 wherein the diagnostic aperture has a length a along the cavity axis of the black driving cavity0With a width of b0And a is a0>b0The length of the ablation layer is a1With a width of b1Then a is1≥a0+200μm，b1≥b0+200μm。
5. The structural target according to any one of claims 2 to 4, wherein the driving black cavity is made of Au and has a straight cylinder structure with an upper opening and a lower opening, disc-shaped shielding plates are arranged on the periphery of the driving black cavity and at a distance of 100 μm from the upper opening and the lower opening of the driving black cavity, the shielding plates are made of Cu, and the surfaces of the shielding plates are coated with CH layers.
6. The structural target of claim 5 wherein said ablative layer is made of a mid-low Z planar material including but not limited to CH, Al, Cu.
7. The structural target of claim 6, wherein the thickness of the ablation layer is 35 μm to 60 μm when the mid-low Z planar material is Al and 25 μm to 40 μm when the mid-low Z planar material is Cu.
8. The structural target of claim 7, wherein when the radiation temperature for driving the black cavity is lower than 140eV, the total thickness of the Au film layer is 3 μm, the thickness of the single Au film layer is 0.3 μm, the Au film layer is 10 layers in total, and the thickness of the spacer layer is 1 μm.
9. The structural target of claim 7Wherein the hard X-ray fraction is M when the radiation temperature of the black cavity is 140eV1% absorption coefficient u of Au film layer1The total thickness of the Au film layer is 3 μm, and the irradiation temperature when driving the black cavity is T2And T is2>At 140eV, the hard X-ray fraction is M2% of Au film layer absorption coefficient is u2Total thickness of Au film layer is t2Then M is1·1404·exp(-u1·3)＝M2·T2 4·exp(-u2·t2)。
10. The structural target of claim 5, wherein the base layer material includes but is not limited to Al, Cu, quartz, polypropylene, and H > D x t, wherein H represents the thickness of the base layer, D represents the shockwave propagation velocity, and t represents the primary lasing time.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN110057789A (en) * | 2019-05-22 | 2019-07-26 | 中国工程物理研究院激光聚变研究中心 | A kind of structure targets of improving laser load shock velocity stability |
| CN114577822A (en) * | 2022-01-20 | 2022-06-03 | 中国工程物理研究院激光聚变研究中心 | Radiation impact target and method for generating radiation impact wave with speed of more than 100km/s in xenon |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110057789A (en) * | 2019-05-22 | 2019-07-26 | 中国工程物理研究院激光聚变研究中心 | A kind of structure targets of improving laser load shock velocity stability |
| CN110057789B (en) * | 2019-05-22 | 2024-05-03 | 中国工程物理研究院激光聚变研究中心 | Structure target for improving laser loading shock wave speed stability |
| CN114577822A (en) * | 2022-01-20 | 2022-06-03 | 中国工程物理研究院激光聚变研究中心 | Radiation impact target and method for generating radiation impact wave with speed of more than 100km/s in xenon |
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