Tb < 3 + >-doped oxyfluoride magneto-optic glass as well as preparation method and application thereof

Abstract

The invention discloses Tb < 3 + >-doped oxyfluoride magneto-optic glass as well as a preparation method and application thereof, and belongs to the field of magneto-optic materials. The Tb < 3 + >-doped oxyfluoride magneto-optic glass comprises main body components and the following main body components in mole percent: 25 to 55 mol percent of B2O3, 0 to 5 mol percent of SiO2, 15 to 30 mol percent of Tb2O3 and 20 to 50 mol percent of TbF3, wherein the sum of the main body components is 100 mol percent; the preparation method comprises the following steps: weighing raw materials, melting in a reducing atmosphere, cooling and molding, and annealing; according to the prepared Tb < 3 + >-doped oxyfluoride magneto-optic glass, the Verdet constant and the transmittance are greatly improved, and the preparation cost of the magneto-optic glass is reduced; and the requirements of laser application, an optical isolator, a magnetic field and an electric field sensor can be better met.

Description

Technical Field

[0001] The invention belongs to the field of magneto-optical materials and relates to a Tb 3+ Oxyfluoride-doped magneto-optical glass and its preparation method and application, especially a high Verdet constant Tb 3+ Oxygen-fluoride-doped magneto-optical glass, preparation method and application thereof. Background Art

[0002] Magneto-optical materials refer to a new type of functional material with Faraday effect. Magneto-optical glass has a high Verdet constant and transparency, and has a broader application prospect in the fields of magneto-optical functional devices, sensor measurement, laser technology, such as magneto-optical switches, magnetic field and current sensors, optical isolators and laser light intensity stabilization components.

[0003] Increasing the absolute value of the Verdet constant is an effective means to improve magneto-optical properties. Among the methods for improving the magneto-optical properties of glass, increasing the rare earth ion doping concentration in the glass becomes the key to improving the magneto-optical properties of glass. 3+ The magneto-optical glass currently studied is terbium-doped heavy lead glass, phosphate glass, germanate glass and silicate glass. However, increasing Tb 3+ The content will lead to a greater tendency of crystallization in the glass; by adjusting the glass matrix to increase the rare earth doping content, a variety of rare earth elements such as Dy that provide magneto-optical properties can also be selected. 3+ 、Ho 3+ , Er 3+ , Pr 3+ etc. for co-doping, but Dy 3+ 、Ho 3+ , Er 3+ , Pr 3+ Rare earth ions have many absorption peaks from visible light to infrared, which reduces the transmittance and is not conducive to the application of magneto-optical glass.

[0004] Patent publication number is CN116102257A, which increases the glass Verdet constant to -146.55rad / (T·m) by adding praseodymium to terbium-doped glass, but the transmittance in the 500nm-1550nm band is poor, and the high price of GeO2 raw materials will greatly increase the manufacturing cost of magneto-optical glass; Patent publication number is CN117682757A, the glass composition is Tb2O3-Dy2O3-B2O3-Ga2O3-Na2O-SiO2-K2O; on the basis of the above components, 0.05wt.%-0.25wt.% Sb2O3 is added, and the transmittance of magneto-optical glass in visible light and near-infrared can reach more than 70%, and the maximum transmittance can reach 85%, but the total content of rare earth ions is low, and the Verdet constant is low. Dy 3+ 、Ho 3+, Er 3+ , Pr 3+ Rare earth ions such as PbO have many absorption peaks, which reduce the transmittance of glass; PbO is not only unfriendly to the human body and the environment, but also easily causes glass coloring. The transmittance of existing magneto-optical glass with relatively high Verdet is generally low. Therefore, the development of magneto-optical glass with high Verdet constant and high transmittance is still a hot spot and difficulty in the current magneto-optical glass field. Summary of the invention

[0005] In view of the problems existing in the above prior art, the present invention provides a Tb 3+ Oxyfluoride-doped magneto-optical glass and its preparation method and application, by combining Tb2O3 and TbF3 to significantly increase the Tb 3+ The Verdet constant of doped oxygen-fluorine magneto-optical glass and the transmittance of magneto-optical glass are improved, which can better meet the requirements of laser applications, optical isolators, magnetic field and electric field sensors.

[0006] In order to achieve the above object, the technical solution adopted by the present invention is as follows:

[0007] A Tb of the present invention 3+ The oxygen-fluoride-doped magneto-optical glass includes main components and the molar percentage of each main component is: B2O3 is 25-55mol%, SiO2 is 0-5mol%, Tb2O3 is 15-30mol%, and TbF3 is 20-50mol%; the sum of all main components is 100mol%.

[0008] Furthermore, TbF3 is preferably 40 mol%.

[0009] The Tb 3+ The Verdet constant of the oxygen-fluoride magneto-optical glass doped at 638nm is -114.21rad / (T·m)~-146.91rad / (T·m), and the Tb 3+ The transmittance of the oxygen-fluoride-doped magneto-optical glass is 80-86% at a wavelength of 500nm-1550nm.

[0010] The present invention provides a Tb 3+ The preparation method of oxygen-fluorine-doped magneto-optical glass comprises the following steps:

[0011] A) According to the Tb 3+ The main components of the oxygen-fluorine-doped magneto-optical glass are weighed in a certain proportion, and the raw materials are fully ground and mixed to obtain glass raw materials;

[0012] B) melting glass raw materials to obtain a uniform glass melt;

[0013] C) Pour the glass melt into a preheated mold, cool it down and then perform annealing at a constant temperature to eliminate internal stress and obtain Tb 3+ Oxyfluoride-doped magneto-optical glass.

[0014] Preferably, in step B), the melting is preferably carried out in a corundum crucible, the melting temperature is 1300-1500° C., the melting time is 60-120 min, the melting atmosphere is a reducing atmosphere, specifically, a reducing gas is introduced, and the reducing gas is preferably one or more of CO, H2, and SiC;

[0015] Preferably, in step C), the preheating temperature of the mold is 400-600°C.

[0016] Preferably, in step C), the annealing temperature is 400-600° C., and the annealing time is 3-8 hours.

[0017] Preferably, in step C), after the annealing, the process further comprises: cooling, wherein the cooling is performed by furnace cooling or temperature reduction cooling, wherein the temperature reduction cooling is performed by cooling the temperature to 200° C. at a cooling rate of 5-10° C. / min, and then cooling the temperature to room temperature with the furnace.

[0018] The present invention also includes a Tb 3+ Application of oxygen-fluoride-doped magneto-optical glass, the above-mentioned Tb 3+ Oxyfluoride-doped magneto-optical glass or the Tb 3+ Tb prepared by the preparation method of oxygen-fluorine-doped magneto-optical glass 3+ Oxyfluoride-doped magneto-optical glass is used in optical isolators, magnetic field sensors, electric field sensors, magneto-optical switches, and laser systems.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] The present invention does not use heavy metal compounds such as Dy, Pb, Ho, Pr and colored rare earth elements, and only uses Tb2O3 and TbF3 in combination to greatly improve the magneto-optical effect of glass. 3+ The Verdet constant of the oxygen-fluoride-doped magneto-optical glass at 638nm is -146.91rad / (T·m), which is greater than the Verdet constant of TGG -131.16rad / (T·m), and it has good transmittance at a wavelength of 500nm-1550nm, with an average transmittance of 83%.

[0021] In particular, TbF3 as a heavy metal fluoride can not only provide high magnetic moment rare earth ion Tb 3+, and can also be used as a flux to reduce the glass melting temperature and viscosity, improve the openness of the glass network structure and the solubility of rare earth oxides in the glass. The combined use of Tb2O3 and TbF3 is beneficial to improving the Verdet constant, and does not contain other rare earth elements, the composition is simpler, and there are fewer absorption peaks. By adding a high content of B2O3, the preparation temperature of the magneto-optical glass is effectively reduced, thereby reducing the preparation cost and difficulty of the magneto-optical glass. SiO2 effectively improves the glass-forming properties and stability of high-content rare earth compound glass. The magneto-optical glass of the present invention does not contain PbO, which is more friendly to the human body and the environment; it does not contain expensive raw materials such as GeO2, and the preparation cost is lower; it does not contain rare earth elements such as Dy, Ho, Er, Pr, the rare earth composition is simpler, and it will not cause glass coloring during the glass melting process. The introduction of a reducing atmosphere can ensure that Tb 3+ Will not be oxidized to diamagnetic and brown Tb 4+ The present invention is convenient for large-scale preparation, can be prepared into large-scale optical devices, and can be drawn into optical fibers. 3+ Oxyfluoride-doped magneto-optical glass has good physical and chemical stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 is the Verdet constant of the magneto-optical glass of Example 1 to Example 4 at 638 nm.

[0023] Figure 2 It is the transmittance of the magneto-optical glass of Example 1 at 200-2000nm.

[0024] Figure 3 It is the transmittance of the magneto-optical glass of Example 2 at 200-2000nm.

[0025] Figure 4 It is the transmittance of the magneto-optical glass of Example 3 at 200-2000nm.

[0026] Figure 5 It is the transmittance of the magneto-optical glass of Example 4 at 200-2000nm.

[0027] Figure 6 This is a picture of the magneto-optical glass morphology of Example 1.

[0028] Figure 7 This is a picture of the magneto-optical glass morphology of Example 2.

[0029] Figure 8 This is a picture of the magneto-optical glass morphology of Example 3.

[0030] Fig. 9 This is a picture of the magneto-optical glass morphology of Example 4.

[0031] Fig.10 It is the transmittance of the magneto-optical glass of comparative example 1 at 200-2000nm.

[0032] Fig.11 It is the transmittance of the magneto-optical glass of comparative example 2 at 200-2000nm.

[0033] Fig.12 This is a picture of the magneto-optical glass morphology of comparative example 1.

[0034] Fig.13 This is a picture of the magneto-optical glass morphology of Comparative Example 2.

[0035] Fig.14 This is a picture of the magneto-optical glass morphology of comparative example 3.

[0036] Fig.15 This is a picture of the magneto-optical glass morphology of comparative example 4. DETAILED DESCRIPTION

[0037] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0038] Example 1

[0039] A Tb 3+ Oxyfluoride-doped magneto-optical glass, the main components and the molar percentage of each main component are: 5SiO2-40B2O3-15Tb2O3-40TbF3;

[0040] 1. According to the above Tb 3+ The main components of the oxygen-fluorine-doped magneto-optical glass are weighed and fully ground and mixed to prepare glass raw materials;

[0041] 2. Pour the mixed glass raw materials into a corundum crucible, introduce CO gas, and melt them into a uniform glass melt in a reducing atmosphere at a melting temperature of 1350°C for 60-120 minutes;

[0042] 3. Pour the glass melt into a mold preheated at 550℃ and cool it into shape. Then transfer it to a 550℃ annealing furnace for constant temperature annealing to eliminate internal stress. After annealing for 3 hours, reduce the temperature to 200℃ at a cooling rate of 5℃ / min, and then cool it to room temperature in the furnace to obtain magneto-optical glass.

[0043] Example 2

[0044] A Tb 3+Oxyfluoride-doped magneto-optical glass, the main components and the molar percentage of each main component are: 5SiO2-35B2O3-20Tb2O3-40TbF3;

[0045] 1. According to the above Tb 3+ The main components of the oxygen-fluorine-doped magneto-optical glass are weighed and fully ground and mixed to prepare glass raw materials;

[0046] 2. Pour the mixed glass raw materials into a corundum crucible, introduce CO gas, and melt them into a uniform glass melt in a reducing atmosphere at a melting temperature of 1350°C for 60-120 minutes;

[0047] 3. Pour the glass melt into a mold preheated at 550℃ and cool it into shape. Then transfer it to a 550℃ annealing furnace for constant temperature annealing to eliminate internal stress. After annealing for 3 hours, reduce the temperature to 200℃ at a cooling rate of 5℃ / min, and then cool it to room temperature in the furnace to obtain magneto-optical glass.

[0048] Example 3

[0049] A Tb 3+ Oxyfluoride-doped magneto-optical glass, the main components and the molar percentage of each main component are: 5SiO2-30B2O3-25Tb2O3-40TbF3;

[0050] 1. According to the above Tb 3+ The main components of the oxygen-fluorine-doped magneto-optical glass are weighed and fully ground and mixed to prepare glass raw materials;

[0051] 2. Pour the mixed glass raw materials into a corundum crucible, introduce CO gas, and melt them into a uniform glass melt in a reducing atmosphere at a melting temperature of 1350°C for 60-120 minutes;

[0052] 3. Pour the glass melt into a mold preheated at 550℃ and cool it into shape. Then transfer it to a 550℃ annealing furnace for constant temperature annealing to eliminate internal stress. After annealing for 3 hours, reduce the temperature to 200℃ at a cooling rate of 5℃ / min, and then cool it to room temperature in the furnace to obtain magneto-optical glass.

[0053] Example 4

[0054] A Tb 3+ Oxyfluoride-doped magneto-optical glass, the main components and the molar percentage of each main component are: 5SiO2-25B2O3-30Tb2O3-40TbF3;

[0055] 1. According to the above Tb 3+ The main components of the oxygen-fluorine-doped magneto-optical glass are weighed and fully ground and mixed to prepare glass raw materials;

[0056] 2. Pour the mixed glass raw materials into a corundum crucible, introduce CO gas, and melt them into a uniform glass melt in a reducing atmosphere at a melting temperature of 1350°C for 60-120 minutes;

[0057] 3. Pour the glass melt into a mold preheated at 550℃ and cool it into shape. Then transfer it to a 550℃ annealing furnace for constant temperature annealing to eliminate internal stress. After annealing for 3 hours, reduce the temperature to 200℃ at a cooling rate of 5℃ / min, and then cool it to room temperature in the furnace to obtain magneto-optical glass.

[0058] The Verdet constants of all magneto-optical glasses are obtained by testing with the Faraday magneto-optical testing system. The transmittance of all magneto-optical glasses is measured by a spectrometer. Figure 1 is the Verdet constant of the magneto-optical glass of Example 1, Example 2, Example 3, and Example 4 at 638 nm. Figure 2-Figure 5 The transmittance of the magneto-optical glass at 200-2000nm is respectively shown in Example 1, Example 2, Example 3 and Example 4. Figure 6-9 The morphology of the magneto-optical glass of Example 1-4 is shown in Table 1. The composition, Verdet constant and transmittance of the high Verdet constant oxygen-fluorine magneto-optical glass of Example 1-4 are shown in Table 1. 3+ Oxyfluoride-doped magneto-optical glass has high Verdet constant and high transmittance. At the same time, the glass is low-cost. Therefore, it is suitable for optical isolators, magnetic field or electric field sensing measurements, magneto-optical switches and laser systems.

[0059] Table 1 Composition of high Verdet constant oxygen-fluorine magneto-optical glass and Verdet constant and transmittance of Example 1-4

[0060]

[0061] Example 5

[0062] A Tb 3+ The oxygen-fluoride-doped magneto-optical glass is the same as that in Example 1, except that, during the preparation process, in step 3, after annealing, it is directly cooled to room temperature in the furnace, and thus also has a high Verdet constant and transmittance.

[0063] Comparative Example 1

[0064] A Tb 3+ The oxygen-fluoride-doped magneto-optical glass includes the main components and the molar percentage of each main component is: B2O3 is 60mol%, SiO2 is 10mol%, and Tb2O3 is 30mol%. Other components are the same as those in Example 1, and the Verdet constant is -71.2rad / (T·m) (see Fig.10), the transmittance is 82.97%. This shows that without adding TbF3, the Verdet constant is small, and its morphology is shown in Fig.12 .

[0065] Comparative Example 2

[0066] A Tb 3+ The oxygen-fluoride-doped magneto-optical glass includes the main components and the molar percentage of each main component is: B2O3 is 50mol%, SiO2 is 10mol%, and TbF3 is 40mol%. Other components are the same as those in Example 1, and the Verdet constant is -77.65rad / (T·m) (see Fig.11 ), the transmittance is 73.98%. This shows that without adding Tb2O3, the Verdet constant is small and the transmittance is reduced. Fig.13 .

[0067] Comparative Example 3

[0068] A Tb 3+ The oxygen-fluorine-doped magneto-optical glass includes the main components and the molar percentages of the main components are: B2O3 is 25mol%, SiO2 is 5mol%, Tb2O3 is 50mol%, and TbF3 is 20mol%. The other components are the same as those in Example 1. The glass is white and opaque, and has lost transparency (see Fig.14 ). This indicates that when Tb2O3 is excessive, the glass becomes devitrified.

[0069] Comparative Example 4

[0070] A Tb 3+ The oxygen-fluorine-doped magneto-optical glass includes the main components and the molar percentages of the main components are: B2O3 is 40mol%, SiO2 is 5mol%, Tb2O3 is 50mol%, and TbF3 is 5mol%; the other components are the same as those in Example 1, and the glass is white and opaque, and has lost transparency (see Fig.15 ). This indicates that when Tb2O3 is excessive and TbF3 is small, the glass becomes devitrified.

[0071] Comparative Example 5

[0072] A Tb 3+ The oxygen-fluoride-doped magneto-optical glass is the same as in Example 1, except that in the preparation process, in step 2, the glass is melted in a non-reducing atmosphere, and the glass is dark brown, which is Tb 4+ The color of the ions increases the absorption of the glass in the ultraviolet band, reduces the transmittance, and Tb 4+ Ions are diamagnetic, which will reduce the Verdet constant.

Claims

1. A Tb 3+ Oxyfluoride-doped magneto-optical glass, characterized by: The Tb 3+ The main components of the oxygen-fluoride-doped magneto-optical glass and the molar percentage of each main component are: B2O3 is 25-55mol%, SiO2 is 0-5mol%, Tb2O3 is 15-30mol%, TbF3 is 20-50mol%, and the sum of all main components is 100mol%.

2. Tb according to claim 1 3+ Oxyfluoride-doped magneto-optical glass, characterized by: The Tb 3+ The Verdet constant of the oxygen-fluoride magneto-optical glass doped at 638nm is -114.21rad / (T·m)~-146.91rad / (T·m), and the Tb 3+ The transmittance of the oxygen-fluoride-doped magneto-optical glass is 80-86% at a wavelength of 500nm-1550nm.

3. Tb according to claim 1 or 2 3+ The preparation method of oxygen-fluorine-doped magneto-optical glass is characterized by: The following steps are involved: A) According to the Tb 3+ The main components of the oxygen-fluorine-doped magneto-optical glass are weighed in a certain proportion, and the raw materials are fully ground and mixed to obtain glass raw materials; B) melting the uniformly mixed glass raw materials to obtain a uniform glass melt; C) pouring the glass melt into a preheated mold, cooling and forming, and then performing a constant temperature annealing treatment to eliminate internal stress to obtain Tb 3+ Oxyfluoride-doped magneto-optical glass.

4. Tb according to claim 3 3+ The preparation method of oxygen-fluorine-doped magneto-optical glass is characterized by: In step B), the melting is carried out using a corundum crucible, the melting temperature is 1300-1500° C., the melting time is 60-120 min, and the melting atmosphere is a reducing atmosphere.

5. Tb according to claim 3 3+ The preparation method of oxygen-fluorine-doped magneto-optical glass is characterized by: In step C), the preheating temperature of the mold is 400-600°C.

6. Tb according to claim 3 3+ The preparation method of oxygen-fluorine-doped magneto-optical glass is characterized by: In step C), the annealing temperature is 400-600° C. and the annealing time is 3-8 hours.

7. The preparation method according to claim 3, characterized in that: In step C), after the annealing, cooling is performed, and the cooling is selected from furnace cooling or temperature reduction cooling, and the temperature reduction cooling is: cooling to 200° C. at a cooling rate of 5-10° C. / min, and then cooling to room temperature with the furnace.

8. A Tb 3+ The application of oxygen-fluorine-doped magneto-optical glass is characterized by: Tb according to claim 1 or 2 3+ Oxyfluoride magneto-optical glass or Tb as described in any one of claims 3-7 3+ Tb prepared by the preparation method of oxygen-fluorine-doped magneto-optical glass 3+ Oxyfluoride-doped magneto-optical glass is used in optical isolators, magnetic field sensors, electric field sensors, magneto-optical switches, and laser systems.

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