阅读说明：本技术 一种磁光晶体、磁光器件及制备方法 (Magneto-optical crystal, magneto-optical device and preparation method ) 是由 李兴旺 梁杰通 杨宇 芦佳 王永国 郑东阳 于 2020-05-25 设计创作，主要内容包括：本发明涉及一种磁光晶体、磁光器件及制备方法,属于光学晶体领域。该磁光晶体的化学式为KTb<Sub>(3-x-y-z-r-w)</Sub>Y<Sub>x</Sub>Gd<Sub>y</Sub>Ho<Sub>z</Sub>Ce<Sub>r</Sub>Pr<Sub>w</Sub>F<Sub>10</Sub>；其中,0.01≤x≤1,0≤y≤1,0≤z≤0.3,0≤r≤0.15,0≤w≤0.15。该磁光晶体不仅具有与KTF晶体相当物化性能,例如晶体热性能和光学性能,还具有更高的维尔德常数,获得显著改善的磁旋光特性。另外,由于Y、Gd、Ho、Ce、Pr的氟化物成本均显著低于TbF<Sub>3</Sub>,利于降低本发明实施例提供的磁光晶体的成本。(The invention relates to a magneto-optical crystal, a magneto-optical device and a preparation method, and belongs to the field of optical crystals. The magneto-optical crystal has a chemical formula of KTb (3‑x‑y‑z‑r‑w) Y x Gd y Ho z Ce r Pr w F 10 (ii) a Wherein x is more than or equal to 0.01 and less than or equal to 1, y is more than or equal to 0 and less than or equal to 1, z is more than or equal to 0 and less than or equal to 0.3, r is more than or equal to 0 and less than or equal to 0.15, and w is more than or equal to 0 and less than or equal to 0.15. The magneto-optical crystal not only has physical and chemical properties equivalent to those of a KTF crystal, such as crystal thermal property and optical property, but also has higher Verdet constant, and obtains significantly improved magneto-optical rotation property. In addition, the fluoride cost of Y, Gd, Ho, Ce and Pr is obviously lower than that of TbF 3 The cost of the magneto-optical crystal provided by the embodiment of the invention is favorably reduced.)

1. A magneto-optical crystal, wherein said magneto-optical crystal has a chemical formula of KTb_{(3-x-y-z-r-w)}Y_xGd_yHo_zCe_rPr_wF₁₀；

Wherein x is more than or equal to 0.01 and less than or equal to 1, y is more than or equal to 0 and less than or equal to 1, z is more than or equal to 0 and less than or equal to 0.3, r is more than or equal to 0 and less than or equal to 0.15, and w is more than or equal to 0 and less than or equal to 0.15.

2. A method of producing a magneto-optical crystal according to claim 1, wherein the method comprises:

providing a feedstock for the production of the magneto-optical crystal according to the formula of the magneto-optical crystal, and placing the feedstock in a crucible, wherein the feedstock comprises: KF. TbF₃、YF₃And optionally GdF₃、HoF₃、CeF₃、PrF₃；

Placing the crucible in a main chamber of a pulling single crystal furnace with the main chamber and a sub-chamber, and carrying out first crystal growth by using a first seed crystal in the main chamber until all floating objects on the surface of melt in the crucible are adhered to the surface of a grown crystal;

taking out the crystal adhered with the floater, replacing a second seed crystal, and then performing second crystal growth in the main chamber by using the second seed crystal to obtain the magneto-optical crystal;

wherein, during the first crystal growth and the second crystal growth, the pulling single crystal furnace is filled with inert gas and CF₄A mixture of gases.

3. A method of producing a magneto-optical crystal according to claim 2, wherein said pulling single crystal furnace is heated by induction heating in performing said first crystal growth and said second crystal growth.

4. A method of manufacturing a magneto-optical crystal according to claim 2, wherein the inert gas and the CF are mixed₄The molar ratio of the gas is 4:1-10: 1.

5. A method of manufacturing a magneto-optical crystal as claimed in claim 4, wherein the inert gas is argon and/or nitrogen.

6. A method of producing a magneto-optical crystal according to claim 2, wherein in said first crystal growth, pulling is performed at a pulling rate of 0.5mm/h to 3.0mm/h, and simultaneously cooling is performed at a cooling rate of 1 ℃/h to 10 ℃/h.

7. A method of producing a magneto-optical crystal as claimed in claim 2, wherein the second seed crystal is caused to enter the melt at a set depth before the second crystal growth is carried out;

and soaking the second seed crystal in the melt at constant temperature for at least 1 hour in a constant diameter state under the conditions of set rotating speed and set heating power.

8. A method of producing a magneto-optical crystal according to claim 2, wherein, when the second crystal growth is performed after the completion of the constant temperature soaking, the pulling is performed at a pulling rate of 0.3mm/h to 2.0mm/h while the temperature is decreased at a cooling rate of 5 ℃/h to 20 ℃/h.

9. A method of manufacturing a magneto-optical crystal according to any one of claims 2 to 8, wherein the seed crystal is a potassium terbium fluoride seed crystal, a potassium yttrium fluoride seed crystal, or a seed crystal manufactured using a magneto-optical crystal according to claim 1.

10. A magneto-optical device, comprising the magneto-optical crystal of claim 1.

Technical Field

The invention relates to the field of optical crystals, in particular to a magneto-optical crystal, a magneto-optical device and a preparation method.

Background

The magneto-optical crystal refers to a kind of optical information functional material which can rotate through the polarization plane of linearly polarized light of the crystal under the action of an external magnetic field, and is widely applied to the fields of optical fiber communication, optical fiber lasers, solid lasers, optical fiber current sensors and the like, so that the magneto-optical crystal is necessary to be provided.

Disclosure of Invention

In view of the above, the present invention provides a magneto-optical crystal, a magneto-optical device and a manufacturing method thereof, which can solve the above technical problems.

Specifically, the method comprises the following technical scheme:

in one aspect, a magneto-optical crystal is provided, the magneto-optical crystal having a chemical formula of KTb₍₃-x-y-z-r-w)Y_xGd_yHo_zCe_rPr_wF₁₀；

Wherein x is more than or equal to 0.01 and less than or equal to 1, y is more than or equal to 0 and less than or equal to 1, z is more than or equal to 0 and less than or equal to 0.3, r is more than or equal to 0 and less than or equal to 0.15, and w is more than or equal to 0 and less than or equal to 0.15.

In another aspect, there is provided a method for producing the magneto-optical crystal, wherein the method comprises:

providing a feedstock for the production of the magneto-optical crystal according to the formula of the magneto-optical crystal, and placing the feedstock in a crucible, wherein the feedstock comprises: KF. TbF₃、YF₃And optionally GdF₃、HoF₃、CeF₃、PrF₃；

Placing the crucible in a main chamber of a pulling single crystal furnace with the main chamber and a sub-chamber, and carrying out first crystal growth by using a first seed crystal in the main chamber until all floating objects on the surface of melt in the crucible are adhered to the surface of a grown crystal;

taking out the crystal adhered with the floater, replacing a second seed crystal, and then performing second crystal growth in the main chamber by using the second seed crystal to obtain the magneto-optical crystal;

wherein, during the first crystal growth and the second crystal growth, the pulling single crystal furnace is filled with inert gas and CF₄A mixture of gases.

In a possible implementation manner, the heating manner of the pulling single crystal furnace is induction heating when the first crystal growth and the second crystal growth are carried out.

In one possible implementation, the inert gas and the CF₄The molar ratio of the gas is 4:1-10: 1.

In one possible implementation, the inert gas is argon and/or nitrogen.

In one possible implementation, in the first crystal growth, pulling is carried out at a pulling rate of 0.5mm/h to 3.0mm/h, and simultaneously, cooling is carried out at a cooling rate of 1 ℃/h to 10 ℃/h.

In one possible implementation, the second seed crystal is allowed to enter the melt at a set depth before the second crystal growth is performed;

and soaking the second seed crystal in the melt at constant temperature for at least 1 hour in a constant diameter state under the conditions of set rotating speed and set heating power.

In a possible implementation manner, after the constant-temperature soaking is finished, the second crystal growth is carried out, pulling is carried out at a pulling speed of 0.3-2.0 mm/h, and meanwhile, the temperature is reduced at a cooling rate of 5-20 ℃/h.

In a possible implementation manner, the seed crystal is a potassium terbium fluoride seed crystal, a potassium yttrium fluoride seed crystal or a seed crystal prepared by using the magneto-optical crystal.

In a further aspect, there is provided a magneto-optical device, comprising any one of the magneto-optical crystals described above.

The technical scheme provided by the embodiment of the invention has the beneficial effects that at least:

the magneto-optical crystal provided by the embodiment of the invention can be called as KTRF crystal for short, wherein R is at least one of Y, Gd, Ho, Ce and Pr. In a potassium terbium fluoride magneto-optical crystal (chemical formula KTb)₃F₁₀Abbreviated as KTF crystal), other trivalent rare earth elements R equivalent to Tb, such as Y and optionally Gd, Ho, Ce, Pr, are doped therein, and since these rare earth elements are equivalent to Tb, the KTRF compound formed by them with K and F has the same crystal structure as the KTF compound. Thus, when all of these trivalent rare earth elements are fused with K element and F element, KTb can be formed as a chemical formula_{(3-x-y-z-r-w)}Y_xGd_yHo_zCe_rPr_wF₁₀The magneto-optical crystal not only has physical and chemical properties equivalent to those of a KTF crystal, such as crystal thermal property and optical property, but also has higher Verdet constant, and obtains obviously improved magneto-optical rotation property. In addition, the cost of the fluoride of Y, Gd, Ho, Ce and Pr is obviously lower than that of TbF₃The cost of the magneto-optical crystal provided by the embodiment of the invention is favorably reduced.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

Fig. 1 is a schematic view of a growth thermal field structure of an exemplary magneto-optical crystal according to an embodiment of the present invention.

The reference numerals denote:

1-copper induction coil, 2-crucible, 3-graphite crucible support, 4-graphite cylinder,

5-graphite transition ring, 6-upper heat preservation graphite felt cylinder and 7-lower heat preservation graphite felt.

Detailed Description

In order to make the technical solutions and advantages of the present invention clearer, the following will describe embodiments of the present invention in further detail with reference to the accompanying drawings.

In one aspect, embodiments of the present invention provide a magneto-optical crystal having a chemical formula of KTb_{(3-x-y-z-r-w)}Y_xGd_yHo_zCe_rPr_wF₁₀；

Wherein x is more than or equal to 0.01 and less than or equal to 1, y is more than or equal to 0 and less than or equal to 1, z is more than or equal to 0 and less than or equal to 0.3, r is more than or equal to 0 and less than or equal to 0.15, and w is more than or equal to 0 and less than or equal to 0.15.

The magneto-optical crystal provided by the embodiment of the invention can be called as KTRF crystal for short, wherein R is at least one of Y, Gd, Ho, Ce and Pr. In a potassium terbium fluoride magneto-optical crystal (chemical formula KTb)₃F₁₀Abbreviated as KTF crystal), other trivalent rare earth elements R equivalent to Tb, such as Y and optionally Gd, Ho, Ce, Pr, are doped therein, and since these rare earth elements are equivalent to Tb, the KTRF compound formed by them with K and F has the same crystal structure as the KTF compound. Thus, when all of these trivalent rare earth elements are fused with K element and F element, KTb can be formed as a chemical formula_{(3-x-y-z-r-w)}Y_xGd_yHo_zCe_rPr_wF₁₀The magneto-optical crystal not only has physical and chemical properties equivalent to those of a KTF crystal, such as crystal thermal property and optical property, but also has higher Verdet constant, and obtains obviously improved magneto-optical rotation property. In addition, the cost of the fluorides of Y, Gd, Ho, Ce and Pr is significantIs significantly lower than TbF₃The cost of the magneto-optical crystal provided by the embodiment of the invention is favorably reduced.

The composition of R is determined according to the trivalent rare earth element specifically contained therein, and R is replaced with the initial letter of the rare earth element symbol. For example, when a Y element is used, the KTRF compound may be abbreviated as KTYF; when the Y element and Gd element are used, the KTRF compound may be abbreviated as KTYGF; when Y element, Gd element, Pr element are used, the KTRF compound can be abbreviated as KTYGPF; by analogy, the embodiments of the present invention are not illustrated herein.

Compared with the KTF crystal, the magneto-optical crystal KTRF provided by the embodiment of the invention has the advantage that Y is introduced into the magneto-optical crystal KTRF³⁺Ions, and optionally Gd³⁺Ion, Ho³⁺Ion, Ce³⁺Ion, Pr³⁺The presence of the ions of the trivalent rare earth elements can not only remarkably improve the Verdet constant of the magneto-optical crystal, but also enable the magneto-optical crystal to have remarkable magnetic gyromagnetic effect. Experiments prove that the Verdet constant of the magneto-optical crystal provided by the embodiment of the invention is remarkably improved compared with that of a KTF crystal, the Verdet constant of the magneto-optical crystal provided by the embodiment of the invention at the 1064nm wavelength can reach 53 at most, and is improved by 47% compared with that of the KTF crystal, but the self-absorption loss at the 1064nm wavelength is basically consistent with that of the KTF crystal, and the experimental data can be shown in Table 1.

Meanwhile, other basic physical properties and chemical properties of the crystal cannot be changed due to the existence of the doped trivalent rare earth elements, so that the basic physical properties and the chemical properties of the magneto-optical crystal are basically unchanged compared with those of a KTF crystal and have equivalent basic properties. The magneto-optical crystal provided by the embodiment of the invention also belongs to a fluoride crystal of a cubic crystal system, has no natural birefringence effect and is an ideal high-power magneto-optical crystal.

On the other hand, the embodiment of the invention also provides a preparation method of the magneto-optical crystal, and specifically, the preparation method comprises the following steps:

providing a starting material for the preparation of the magneto-optical crystal according to the chemical formula of the magneto-optical crystal, andplacing a feedstock in a crucible, wherein the feedstock comprises: KF. TbF₃、YF₃And optionally GdF₃、HoF₃、CeF₃、PrF₃。

The crucible is placed in a main chamber of a single crystal pulling furnace having the main chamber and a sub-chamber, and a first crystal growth is performed in the main chamber using a first seed crystal until all floating materials on the surface of a melt inside the crucible adhere to the surface of the grown crystal.

And taking out the crystal adhered with the floater, replacing the second seed crystal, and then performing secondary crystal growth in the main chamber by using the second seed crystal to obtain the magneto-optical crystal.

Wherein, during the first crystal growth and the second crystal growth, inert gas and CF are filled in the pulling single crystal furnace₄A mixture of gases.

The magneto-optical crystal has a chemical formula of KTb_{(3-x-y-z-r-w)}Y_xGd_yHo_zCe_rPr_wF₁₀(ii) a Wherein x is more than or equal to 0.01 and less than or equal to 1, y is more than or equal to 0 and less than or equal to 1, z is more than or equal to 0 and less than or equal to 0.3, r is more than or equal to 0 and less than or equal to 0.15, and w is more than or equal to 0 and less than or equal to 0.15.

The preparation method of the magneto-optical crystal provided by the embodiment of the invention is suitable for preparing the magneto-optical crystal provided by the embodiment of the invention by improving the current general preparation method of the KTF crystal. Specifically, the method comprises the following steps:

(1) in the growth process of the KTF crystal, the adopted growth atmosphere is HF atmosphere, the HF atmosphere has high corrosion resistance requirement on equipment, tail gas treatment is troublesome, and the growth process is difficult to stabilize. Based on the above, in the embodiment of the invention, when the magneto-optical crystal is grown, the growth atmosphere adopted is inert gas and CF₄Mixture of gases due to CF₄The gas is nontoxic and has significantly lower corrosivity than CF₄The gas can effectively solve the technical problems of high corrosion resistance requirement on equipment, troublesome tail gas treatment and difficult stabilization of the growth process, reduces the corrosion on the equipment, ensures that the preparation process is safe and nontoxic, and has stable and reliable preparation process, simplicity, convenience and easy operation.

Wherein, CF₄The gas can generate decomposition reaction with the residual water in the system at high temperature to generate HF gas,the HF component can undergo a fluorination reaction with the oxyfluoride formed in the melt, thereby converting the oxyfluoride to fluoride, which facilitates the elimination of floaters. In addition, the mixed gas also contains inert gas, and the inert gas can be argon and/or nitrogen by way of example.

Wherein the inert gas and CF₄The gas molar ratio is 4:1-10:1, such as 4:1, 5:1, 6:1, 7:1, 8:1, 9:1, 10:1, etc., and the effect of protecting the crystal growth process and inhibiting the generation of floaters is achieved by the above ratio.

(2) Due to CF₄The reactivity of the gas is weaker than that of HF gas, and it is difficult to sufficiently suppress moisture adsorbed in a highly hygroscopic raw material such as KF, which causes a problem that floating materials such as TbOF are generated at the initial stage of crystal growth. Based on the above, the method provided by the embodiment of the invention utilizes the first seed crystal to perform the first crystal growth in the main chamber, and utilizes the grown crystal to adhere to the floating objects on the surface of the melt in the crucible, so as to overcome the influence of the floating objects, and improve the stability of the subsequent crystal growth and the controllability of the process quality. And subsequently, the crystal adhered with the floater is taken out, and a new second seed crystal is utilized to carry out second crystal growth in the main chamber, so that the high-quality magneto-optical crystal can be obtained.

Wherein, in the preparation of the magneto-optical crystal, the magneto-optical crystal is prepared according to the chemical formula KTb_{(3-x-y-z-r-w)}Y_xGd_yHo_zCe_rPr_wF₁₀The preset x, y, z, r and w values can determine KF and TbF₃、YF₃、GdF₃、HoF₃、CeF₃、PrF₃The mass ratio of (a). Further, the specific mass of each raw material is further determined according to the volume of the crucible and the density of a melt in which the raw materials are dissolved in the subsequent crucible.

In the embodiment of the present invention, the purity of each raw material is more than 99.99% to ensure the crystal quality, and the crucible used may be a Pt crucible (platinum crucible) or an Ir crucible.

YF₃And optionally GdF₃、HoF₃、CeF₃、PrF₃The cost of the raw materials is low, so that the invention is practicalThe example provides a reduction in the cost of growing magneto-optical crystals of up to 20%, and the experimental data can be found in table 1.

Due to KF and TbF₃、YF₃、GdF₃And optionally a HoF₃、CeF₃、PrF₃The melt formed after the raw materials are melted has higher viscosity, and is heated by adopting a resistance heating mode, so that a larger temperature gradient is not easy to construct in the melt, the heat and mass transport capacity in the melt is poor, and high-quality large-size single crystals are difficult to grow. Based on the technical problem, when the first crystal growth and the second crystal growth are carried out, the heating mode of the pulling single crystal furnace is induction heating, and the induction heating mode is used for replacing a resistance heating mode, so that the convection of a melt in the crucible can be enhanced, the solute transport capacity is improved, and the high-quality large-size magneto-optical crystal can be obtained.

The first seed crystal and the second seed crystal are potassium terbium fluoride seed crystals (KTF seed crystals), potassium yttrium fluoride seed crystals (KYF seed crystals) or seed crystals prepared by utilizing the magneto-optical crystal provided by the embodiment of the invention, so that smooth growth of single crystals is ensured.

The crystal growing furnace used in the embodiment of the invention is a pulling single crystal furnace (also called a straight pulling single crystal furnace) with a main chamber and an auxiliary chamber, in particular to an upper weighing automatic diameter control pulling single crystal furnace. As shown in figure 1, a copper induction coil 1 is arranged in a hearth of the pulling single crystal furnace to ensure that the induction heating can be realized. When the crucible 2 is placed in a single crystal pulling furnace, the axis of the crucible 2 is concentric with the axis of the copper induction coil 1, the pot mouth of the crucible 2 is flush with the copper induction coil 1, and the pot bottom of the crucible 2 is supported by a graphite pot holder 3. The lateral part of crucible 2 utilizes graphite section of thick bamboo 4 to encircle to, graphite transition ring 5 is still installed to the top of graphite section of thick bamboo 4, and heat preservation graphite felt section of thick bamboo 6 is installed to the top of graphite transition ring 5, and the bottom of crucible 2 utilizes heat preservation graphite felt 7 to support down.

The main chamber of the single crystal pulling furnace is arranged at the lower part, the auxiliary chamber is arranged at the upper part, a baffle valve is arranged between the main chamber and the auxiliary chamber, when the baffle valve is opened, the main chamber is communicated with the auxiliary chamber, otherwise, when the baffle valve is closed, the main chamber is isolated from the auxiliary chamber and is not communicated. The main chamber and the sub-chamber have respective separate doors to facilitate respective operations, and the evacuation and the inflation operations of the main chamber and the sub-chamber are also performed separately from each other.

The specific operation steps involved in the preparation method of the magneto-optical crystal are explained by combining the crystal pulling single crystal furnace with the structure as follows:

installing the first seed crystal on the seed crystal rod, starting the crystal rotating to make the axle center of the first seed crystal consistent with that of the crucible, closing the furnace door to communicate the main chamber with the auxiliary chamber, starting the vacuum system of the single crystal furnace to vacuumize the hearth, and when the vacuum degree in the hearth is lower than 5 × 10^-3After Pa, filling mixed gas with purity higher than 4N to between 0.11 and 0.14 MPa.

Starting an induction heating power supply, carrying out induction heating by using a copper induction coil, heating to 750-800 ℃ at a heating rate of 50-100 ℃/h, and then heating to melt the raw materials in the crucible at a heating rate of 5-20 ℃/h.

And after the raw materials in the crucible are completely melted into a melt, moving the first seed crystal downwards, observing through an observation window arranged at the top of the auxiliary chamber, and allowing the first seed crystal to be in contact with the liquid level of the melt and enter 1-3 mm below the liquid level of the melt.

And starting crystal rotation, controlling the rotation speed to be 8-20 rpm, and keeping the first seed crystal in the same diameter (not thickening nor thinning) by adjusting the heating power. Then pulling at a pulling speed of 0.5-3.0 mm/h, and simultaneously cooling at a cooling speed of 1-10 ℃/h to ensure that the first seed crystal gradually enlarges and grows crystals, so that the floating materials on the surface of the melt are gradually adhered to the surfaces of the grown crystals. And when all the floating objects on the surface of the melt are clean, quickly moving the seed rod upwards, separating the crystal adhered with the floating objects from the melt, and continuously moving the seed rod upwards until all the crystal adhered with the floating objects enter the auxiliary chamber.

Closing a baffle valve between the main chamber and the auxiliary chamber to isolate the main chamber and the auxiliary chamber from each other, vacuumizing the auxiliary chamber, stopping vacuumizing after the vacuum degree is as low as 10Pa, deflating the auxiliary chamber until the air pressure in the auxiliary chamber is balanced with the air pressure outside the hearth, opening a furnace door of the auxiliary chamber, taking down the first seed crystals and the crystals adhered with the floaters from the seed crystal rod, installing new second seed crystals on the seed crystal rod, and closing the furnace door of the auxiliary chamber after adjusting the axle center of the first seed crystals to be consistent with the axle center of the crucible.

The sub-chamber is vacuumized again when the vacuum degree is as low as 5 × 10^-3And after Pa, filling high-purity mixed gas into the hearth until the gas pressure in the auxiliary chamber is balanced with the gas pressure in the main chamber, wherein the composition of the mixed gas in the auxiliary chamber is consistent with that of the mixed gas in the main chamber.

And opening the baffle valve again to communicate the main chamber with the auxiliary chamber, moving down the second seed crystal, and observing through an observation window arranged at the top of the auxiliary chamber to ensure that the depth of the second seed crystal entering the melt is 1-3 mm. And starting crystal rotation, enabling the rotation speed to be 4-15 rpm, adjusting the heating power, and soaking the seed crystals for at least 1h after the second seed crystals are not thickened or thinned.

Then, pulling at a pulling speed of 0.3mm/h-2.0mm/h (ensuring that high-quality single crystal grows while taking efficiency into consideration), adjusting heating power to perform shouldering growth of the magneto-optical crystal, and adjusting the heating power to enable the magneto-optical crystal to grow in an equal diameter after the diameter of the magneto-optical crystal reaches a preset value. When the constant diameter length of the magneto-optical crystal reaches a preset length, namely after the constant diameter growth process is finished, quickly pulling off the magneto-optical crystal from the surface of the melt until the distance between the tail end of the magneto-optical crystal and the liquid level of the melt is 10-30 mm, stopping pulling, and then keeping the state unchanged for 0.5-2.0 h.

Controlling the cooling rate to be 5-20 ℃/h (ensuring that the crystal is prevented from cracking while the efficiency is considered), cooling until the temperature in the hearth is reduced to room temperature, then discharging the gas in the hearth, opening the furnace door, and taking out the grown magneto-optical crystal.

And processing the magneto-optical crystal element with required specification and size from the grown magneto-optical crystal by adopting a crystal cutting and processing method commonly used in the field.

In another aspect, embodiments of the present invention provide a magneto-optical device including the magneto-optical crystal as described above.

Wherein the magneto-optical crystal has a chemical formula of KTb_{(3-x-y-z-r-w)}Y_xGd_yHo_zCe_rPr_wF₁₀；0.01≤x≤1，0≤y≤1，0≤z≤0.3，0≤r≤0.15，0≤w≤0.15。

The magneto-optical crystal provided by the embodiment of the invention has the advantages of low self-absorption loss, large Verdet constant, small thermo-optic coefficient and nonlinear coefficient and the like, and is suitable for preparing high-power magneto-optical devices, such as power above hectowatt or even kilowatt. Illustratively, the magneto-optical device includes, but is not limited to: faraday rotator, optical isolator, etc.

The invention will be further described by the following specific examples: