Accurate single alkali metal atom filling method for alkali metal gas chamber

Abstract

The invention belongs to the technical field of alkali metal atom gas chambers, and particularly relates to an alkali metal gas chamber-oriented single alkali metal atom accurate filling method, which specifically comprises a single alkali metal atom accurate filling theoretical method. A temperature gradient construction method; a technical method for accurately acquiring single alkali metal atoms; the invention discloses a quantitative filling technical method for single alkali metal atoms based on temperature gradient. The problems that in the prior art, when the alkali metal gas chamber is filled with single alkali metal atoms through cooperation of a traditional artificial flame repelling method and an online density detection method, the accuracy is low, quantitative control cannot be achieved, and the production efficiency is low are solved; by means of the method, automatic accurate filling of quantitative single alkali metal atoms can be achieved, the whole process is easy to operate, the filling time is greatly shortened, and the filling precision is high.

Description

Technical Field

[0001] The invention belongs to the technical field of alkali metal atom gas chambers, and in particular relates to a method for accurately filling a single alkali metal atom into an alkali metal gas chamber. Background Art

[0002] The Spin Exchange Relaxation Free (SERF) atomic gyroscope is based on quantum physics and can greatly improve the accuracy of inertial navigation and guidance. It is one of the representatives of the third generation of ultra-high precision atomic inertial measurement instruments. Compared with the second generation of inertial measurement instruments based on optics, its theoretical accuracy can be improved by orders of magnitude.

[0003] The alkali metal atomic gas chamber is the core sensitive component of the SERF atomic gyroscope, which mainly includes alkali metal atomic vapor, buffer gas and quenching gas. As one of the important working media in the gas chamber, alkali metal atomic vapor contains all the information of the SERF atomic gyroscope during operation. Therefore, accurately controlling the amount of alkali metal atoms filled in the gas chamber is of great significance for verification experimental research, improving gas chamber performance, and greatly improving the performance indicators of the SERF atomic gyroscope.

[0004] In the current technology, the alkali metal atom filling method has the traditional manual method, which has the disadvantage of relying on the experience of workers and visually observing the size of the alkali metal atom condensation droplets to determine the filling amount; Patent document: CN201611037423, a method for precise filling of double alkali metal atoms, also proposed a method for online measurement of alkali metal atom density based on spectral analysis to control the filling amount, but there are problems such as low measurement accuracy and poor consistency. Therefore, it is urgent to provide a single alkali metal atom precise filling method for alkali metal gas chambers, which mainly involves the quantitative preparation and complete filling of single alkali metal atoms. Summary of the invention

[0005] In view of the problems that the existing alkali metal atom filling technology in gas chambers has low precision and poor consistency of filling amount, which leads to a significant decrease in gas chamber performance, the present invention proposes a single alkali metal atom precise filling method for alkali metal gas chambers. This method can achieve precise quantitative control of alkali metal atom filling and greatly shorten the time required for complete filling.

[0006] The technical solution of the present invention is as follows:

[0007] A method for accurately filling a single alkali metal atom into an alkali metal gas chamber, characterized by comprising the following steps:

[0008] Step 1, using a single alkali metal atom precise filling theoretical method to establish an alkali metal gas chamber filling platform model, wherein the alkali metal gas chamber filling platform model includes establishing a temperature gradient based on molecular diffusion mass transfer theory to drive the movement of alkali metal vapor, so that alkali metal atoms are unidirectionally deposited into the alkali metal gas chamber;

[0009] Step 2, constructing a temperature gradient to ensure that a certain amount of alkali metal atoms are completely unidirectionally deposited into the alkali metal gas chamber, including placing the glass main pipe in a high temperature area by using an oven heating system, placing the alkali metal gas chamber in a low temperature area by using a water cooling system, and connecting the alkali metal gas chamber to the glass main pipe through a connecting pipe to form a temperature gradient;

[0010] Step 3, accurately obtaining the amount of single alkali metal atoms required for the alkali metal gas chamber, including calculating the amount of reactants using the chloride reduction method, the chemical reaction formula is as follows:

[0011]

[0012] Wherein X is a single alkali metal, X is potassium, rubidium or cesium, and after the reaction is completed, a mixture containing X and BaCl is prepared. 2 A solid powder, wherein the X content in the solid powder is the amount required for a single alkali metal atom;

[0013] Step 4, vacuum heating the solid powder in a tube furnace until the single alkali metal atoms in the solid powder are vaporized and enter the main glass channel, and the temperature gradient in step 2 is used to make the single alkali metal atoms unidirectionally deposit into the alkali metal gas chamber to complete the filling of the alkali metal gas chamber.

[0014] Step 1 includes the following expression for the particle deposition process using the diffusion equation in mass transfer:

[0015]

[0016] Where ρ represents the gas concentration, t represents the time, represents the velocity field, represents the gradient operator, D represents the diffusion coefficient, and R represents the source term, which is a term that describes the influence of the concentration of a substance in space and time. represents the mean free path of gas molecules, k is the Boltzmann constant, T is the Kelvin temperature, d is the effective molecular diameter, and p is the gas pressure. is the Maxwell-Boltzmann distribution function, m is the gas molecular mass, and e is a natural constant.

[0017] Step 2 includes the oven heating system heating the temperature in the heating chamber to 230°C to 300°C, the main glass pipeline in the glass pipeline is placed in the heating chamber, and the water cooling system keeps the ambient temperature of the alkali metal gas chamber constant at 20°C.

[0018] Step 2 includes connecting the glass main pipeline to a plurality of alkali metal gas chambers via connecting pipelines.

[0019] Step 4 includes heating the tube furnace to 300° C. to vaporize all the single alkali metal atoms in the solid powder, so as to accurately obtain the required amount of single alkali metal atoms for the alkali metal gas chamber.

[0020] Step 4 includes a vacuum system connected to the tube furnace, and the working vacuum degree reaches 5×10 -6 Pa, vacuum leakage rate up to 1×10 -8 PaL / S.

[0021] The technical effects of the present invention are as follows: The present invention provides a method for accurately filling a single alkali metal atom into an alkali metal gas chamber, which solves the problems of low accuracy, inability to quantitatively control, and low production efficiency in the prior art of filling a single alkali metal atom into an alkali metal gas chamber by combining a traditional artificial flame driving method with an online density detection method. The present invention can realize automatic and accurate filling of quantitative single alkali metal atoms, the entire process is simple to operate, the filling time is greatly reduced, and the filling accuracy is high.

[0022] Compared with the prior art, the present invention has the following characteristics:

[0023] 1. The present invention is a method for accurately filling a single alkali metal atom into an alkali metal gas chamber. The whole method involves a simple process flow, and the automated filling can greatly shorten the filling time and improve the filling efficiency.

[0024] 2. The quantitative alkali metal atomic single substance is prepared in advance by using the chloride reduction method combined with the temperature gradient theory. Compared with the traditional manual visual method and the density detection method based on spectral absorption, the filling accuracy is higher;

[0025] 3. This method can achieve precise filling of single alkali metal atoms, improve the performance of the entire gas chamber, and thus improve the overall performance of the SERF atomic inertial gyroscope. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 The present invention is a schematic diagram of the structure of a filling device involved in a method for accurately filling a single alkali metal atom facing an alkali metal gas chamber according to the present invention.

[0027] Figure 2 The present invention is a schematic flow chart of a method for accurately filling a single alkali metal atom into an alkali metal gas chamber according to the present invention. Figure 2The method comprises the steps of: 1, establishing an alkali metal gas chamber filling platform model by using a single alkali metal atom accurate filling theoretical method, wherein the alkali metal gas chamber filling platform model comprises establishing a temperature gradient based on the molecular diffusion mass transfer theory to drive the alkali metal vapor to move, so that the alkali metal atoms are deposited unidirectionally into the alkali metal gas chamber; 2, constructing a temperature gradient to ensure that a quantitative amount of alkali metal atoms are completely deposited unidirectionally into the alkali metal gas chamber, comprising heating the glass main line to 300° C. by using an oven heating system, keeping the ambient temperature of the alkali metal gas chamber constant to 20° C. by using a water cooling system, and connecting the alkali metal gas chamber to the glass main line through a connecting pipe to form a temperature gradient; and 3, accurately obtaining the required amount of single alkali metal atoms for the alkali metal gas chamber, comprising calculating the amount of reactants by using a chloride reduction method ( wherein X is a monoalkali metal), preparing a reactant solid powder; step 4, heating the solid powder in a tube furnace under vacuum until the monoalkali metal atoms in the solid powder are vaporized and enter the glass main line, and the filling is completed using the temperature gradient in step 2.

[0028] The reference numerals are as follows: 1-glass pipeline; 2-alkali metal gas chamber; 3-vacuum extraction system; 4-tube furnace; 5-water cooling system; 6-oven heating system. DETAILED DESCRIPTION

[0029] Below is the attached figure ( Figure 1-Figure 2 ) and Examples illustrate the present invention.

[0030] Figure 1 The present invention is a schematic diagram of the structure of a filling device involved in a method for accurately filling a single alkali metal atom facing an alkali metal gas chamber according to the present invention. Figure 2 This is a schematic diagram of the process of implementing a method for accurately filling a single alkali metal atom into an alkali metal gas chamber according to the present invention. Figure 1 to Figure 2 As shown, a method for accurately filling a single alkali metal atom into an alkali metal gas chamber comprises the following steps: step 1, establishing an alkali metal gas chamber filling platform model using a theoretical method for accurately filling a single alkali metal atom, wherein the alkali metal gas chamber filling platform model comprises establishing a temperature gradient based on molecular diffusion mass transfer theory to drive the movement of alkali metal vapor, so that alkali metal atoms are deposited unidirectionally into the alkali metal gas chamber 2; step 2, constructing a temperature gradient to ensure that a certain amount of alkali metal atoms are completely deposited unidirectionally into the alkali metal gas chamber 2, comprising placing a glass main line (one of the components in the glass line 1) in a high temperature region using an oven heating system 6, placing the alkali metal gas chamber 2 in a low temperature region using a water cooling system 5, and connecting the alkali metal gas chamber 2 to the glass main line via a connecting line (one of the components in the glass line 1) to form a temperature gradient; step 3, accurately obtaining the required amount of single alkali metal atoms for the alkali metal gas chamber 2, comprising calculating the amount of reactants using a chloride reduction method, and the chemical reaction formula is as follows:

[0031]

[0032] Wherein X is a single alkali metal, X is potassium, rubidium or cesium, and after the reaction is completed, a mixture containing X and BaCl is prepared. 2 A solid powder, wherein the X content in the solid powder is the amount required for a single alkali metal atom;

[0033] In step 4, the solid powder is vacuum-heated in a tube furnace 4 (the vacuum environment is achieved by a vacuum pumping system 3) until the monoalkali metal atoms in the solid powder are vaporized and enter the main glass line, and the temperature gradient in step 2 is used to cause the monoalkali metal atoms to unidirectionally deposit into the alkali metal gas chamber, thereby completing the filling of the alkali metal gas chamber.

[0034] Step 1 includes the following expression for the particle deposition process using the diffusion equation in mass transfer:

[0035]

[0036] Where ρ represents the gas concentration, t represents the time, represents the velocity field, represents the gradient operator, D represents the diffusion coefficient, and R represents the source term, which is a term that describes the influence of the concentration of a substance in space and time. represents the mean free path of gas molecules, k is the Boltzmann constant, T is the Kelvin temperature, d is the effective molecular diameter, and p is the gas pressure. is the Maxwell-Boltzmann distribution function, m is the gas molecular mass, and e is a natural constant.

[0037] Step 2 includes the oven heating system 6 heating the temperature in the heating chamber to 230° C. to 300° C., the main glass pipe in the glass pipe 1 is placed in the heating chamber, and the water cooling system 5 keeps the ambient temperature of the alkali metal gas chamber 2 constant to 20° C. Step 2 includes the main glass pipe being connected to a plurality of alkali metal gas chambers via connecting pipes.

[0038] Step 4 includes heating the tube furnace 4 to 300°C to vaporize all the single alkali metal atoms in the solid powder, so as to accurately obtain the required amount of single alkali metal atoms for the alkali metal gas chamber. Step 4 includes connecting the tube furnace 4 to a vacuum system 3, with a working vacuum degree of 5×10 -6 Pa, vacuum leakage rate up to 1×10 -8 PaL / S.

[0039] The present invention belongs to the technical field of alkali metal atom gas chambers, and specifically relates to a method for accurately filling single alkali metal atoms into alkali metal gas chambers. Specifically, the following steps are included: a theoretical method for accurately filling single alkali metal atoms; a method for constructing a temperature gradient; a technical method for accurately obtaining single alkali metal atoms; and a technical method for quantitatively filling single alkali metal atoms based on a temperature gradient. The present invention solves the problems in the prior art of low accuracy, inability to quantitatively control, and low production efficiency in filling single alkali metal atoms into alkali metal gas chambers by combining the traditional artificial flame driving method with the online density detection method; the method can realize automated and accurate filling of quantitative single alkali metal atoms, the entire process is simple to operate, the filling time is greatly reduced, and the filling accuracy is high.

[0040] A method for accurately filling a single alkali metal atom into an alkali metal gas chamber comprises the following steps:

[0041] Step 1, single alkali metal atom precise filling theoretical method;

[0042] Step 2, temperature gradient construction method;

[0043] Step 3, technical method for accurately obtaining single alkali metal atoms;

[0044] Step 4: quantitative filling technology of single alkali metal atoms based on temperature gradient.

[0045] like Figure 1 As shown, the single alkali metal atom precise filling equipment facing the alkali metal gas chamber includes a glass pipeline 1, an alkali metal gas chamber 2, a vacuum system 3, a tubular furnace 4 for mixing powders to react, a liftable water cooling system 5, and a liftable oven heating system 6.

[0046] like Figure 2 As shown, a method process for accurately filling a single alkali metal atom with alkali metal gas chamber includes a theoretical method for accurately filling a single alkali metal atom with alkali metal gas chamber, a temperature gradient construction method, a technical method for accurately acquiring a single alkali metal atom, and a technical method for quantitatively filling a single alkali metal atom with alkali metal gas chamber based on temperature gradient.

[0047] Step 1: Single alkali metal atom precise filling theoretical method.

[0048] According to the molecular diffusion mass transfer theory, alkali metal vapor will move due to the existence of temperature gradient and cause unidirectional deposition.

[0049] In mass transfer, the particle deposition process is described using the diffusion equation:

[0050]

[0051] Where ρ represents gas concentration; t represents time; represents the velocity field; represents the gradient operator; D represents the diffusion coefficient; R represents the source term, which is a term that describes the influence of the concentration of a substance in space and time.

[0052] The theoretical formula for gas diffusion coefficient is:

[0053]

[0054] in The expression for the mean free path of gas molecules is:

[0055]

[0056] Where k is the Boltzmann constant; T is the Kelvin temperature; d is the effective molecular diameter; and p is the gas pressure.

[0057] Velocity Field It can be described using the Maxwell-Boltzmann distribution, where m is the molecular mass of the gas:

[0058]

[0059] It is deduced that the diffusion coefficient follows the relationship between temperature and pressure:

[0060]

[0061] Therefore, the diffusion coefficient of the molecules can be affected by changing the temperature and pressure during the filling process of the alkali metal atoms, thereby controlling the molecular diffusion rate. At the same time, the precise control of the alkali metal filling amount can be achieved by controlling the time of the entire filling process.

[0062] According to the above theory, we first physically model the automatic alkali metal gas chamber filling platform. Secondly, we comprehensively consider theoretical factors such as thermodynamics, kinetics, and fluid mechanics of the entire alkali metal atomic evaporation and deposition process to construct a comprehensive and accurate theoretical framework. Finally, we set the corresponding temperature field and vacuum conditions, and simulate the precise filling process of single alkali metal atoms in the entire gas chamber in the simulation software, which can cover multiple stages such as atomic evaporation, migration, deposition, and possible surface reconstruction, thereby achieving a comprehensive and detailed simulation of the entire filling process to ensure the rationality of the entire process and to verify it with subsequent experimental results.

[0063] Step 2, temperature gradient construction method.

[0064] An oven heating system 6 and a water cooling system 5 are provided in the single alkali metal atom automatic filling platform. The glass pipeline 1 includes a glass main pipeline, a connecting pipeline, and an alkali metal gas chamber. The temperature of the oven heating system is controllable and can be heated to about 300°C; the temperature of the water cooling system is controllable and can maintain a constant temperature of 20°C; the glass main pipeline is placed in the oven heating system, and the alkali metal gas chamber is placed in the water cooling system, and the alkali metal gas chamber is connected to the glass main pipeline through a connecting pipe; the oven heating system provides a high temperature area, and the water cooling system provides a low temperature area, and the two construct a temperature gradient. Through this temperature gradient construction method, after a certain period of time, it can be guaranteed that a certain amount of alkali metal atoms are completely unidirectionally deposited into the alkali metal gas chamber.

[0065] Step 3: Technical method for accurately obtaining single alkali metal atoms.

[0066] In this embodiment, the chloride reduction method is used to accurately obtain quantitative single alkali metal atoms. The alkali metal atom source type is selected as rubidium (Rb), and the mass of alkali metal rubidium required in each gas chamber is set to 200 μg. There are 10 gas chambers 2 connected in the glass pipe 1, so the mass of alkali metal rubidium required is 2 mg.

[0067] According to the following reaction equation:

[0068]

[0069] Therefore, the required mass of each of the two reactants can be calculated:

[0070]

[0071]

[0072] After weighing, the corresponding solutions are prepared and poured into the reaction boat together, and the mixed solution of the reactants is evaporated and dried into a mixed powder in a vacuum drying oven. The solid powder of the reactants is heated at high temperature in a tubular furnace to accurately obtain the required amount of single alkali metal atoms.

[0073] The step 4 includes a vacuum system 3, a tube furnace 4, an oven heating system 6, a water cooling system 5, and the glass pipeline 1 includes a glass main pipeline, a connecting pipeline, and an alkali metal gas chamber. The specific method is:

[0074] Step 401: Start the vacuum system, and the working vacuum degree can reach 5×10 -6 Pa, vacuum leakage rate can reach 1×10 -8 PaL / S;

[0075] Step 402: Turn on the oven heating system to perform high-temperature impurity removal;

[0076] Step 403: The tube furnace is heated to 300°C to vaporize the single alkali metal atoms, the oven heating system temperature is raised to 230°C to provide a high temperature area, and the water cooling system temperature is kept constant at 20°C to provide a low temperature area. The two construct a temperature gradient, and all systems operate stably within a preset theoretical time period. Alkali metal atoms are unidirectionally deposited into the alkali metal gas chamber to complete the filling;

[0077] Step 404: Remove the alkali metal gas cell.

[0078] The contents not described in detail in the specification of the present invention belong to the prior art known to the professional and technical personnel in the field. It is pointed out here that the above description helps those skilled in the art to understand the invention, but does not limit the protection scope of the invention. Any equivalent replacement, modification and / or simplification of the above description without departing from the essence of the invention falls within the protection scope of the invention.

Claims

1. A method for accurately filling a single alkali metal atom into an alkali metal gas chamber, characterized in that: The following steps are involved: Step 1, using a single alkali metal atom precise filling theoretical method to establish an alkali metal gas chamber filling platform model, wherein the alkali metal gas chamber filling platform model includes establishing a temperature gradient based on molecular diffusion mass transfer theory to drive the movement of alkali metal vapor, so that alkali metal atoms are unidirectionally deposited into the alkali metal gas chamber; Step 2, constructing a temperature gradient to ensure that a certain amount of alkali metal atoms are completely unidirectionally deposited into the alkali metal gas chamber, including placing the glass main pipe in a high temperature area by using an oven heating system, placing the alkali metal gas chamber in a low temperature area by using a water cooling system, and connecting the alkali metal gas chamber to the glass main pipe through a connecting pipe to form a temperature gradient; Step 3, accurately obtaining the amount of single alkali metal atoms required for the alkali metal gas chamber, including calculating the amount of reactants using the chloride reduction method, the chemical reaction formula is as follows: Wherein X is a single alkali metal, X is potassium or rubidium or cesium, and after the reaction is completed, a solid powder containing X and BaCl2 is prepared, and the content of X in the solid powder is the amount required for the single alkali metal atom; Step 4, vacuum heating the solid powder in a tube furnace until the single alkali metal atoms in the solid powder are vaporized and enter the main glass channel, and the temperature gradient in step 2 is used to make the single alkali metal atoms unidirectionally deposit into the alkali metal gas chamber to complete the filling of the alkali metal gas chamber.

2. The method for accurately filling a single alkali metal atom into an alkali metal gas chamber according to claim 1, characterized in that: Step 1 includes the following expression for the particle deposition process using the diffusion equation in mass transfer: Where ρ represents the gas concentration, t represents the time, represents the velocity field, represents the gradient operator, D represents the diffusion coefficient, and R represents the source term, which is a term that describes the influence of the concentration of a substance in space and time. represents the mean free path of gas molecules, k is the Boltzmann constant, T is the Kelvin temperature, d is the effective molecular diameter, and p is the gas pressure. is the Maxwell-Boltzmann distribution function, m is the gas molecular mass, and e is a natural constant.

3. The method for accurately filling a single alkali metal atom into an alkali metal gas chamber according to claim 1, characterized in that: Step 2 includes the oven heating system heating the temperature in the heating chamber to 230°C to 300°C, the main glass pipeline in the glass pipeline is placed in the heating chamber, and the water cooling system keeps the ambient temperature of the alkali metal gas chamber constant at 20°C.

4. The method for accurately filling a single alkali metal atom into an alkali metal gas chamber according to claim 1, characterized in that: Step 2 includes connecting the glass main pipeline to a plurality of alkali metal gas chambers via connecting pipelines.

5. The method for accurately filling a single alkali metal atom into an alkali metal gas chamber according to claim 1, characterized in that: Step 4 includes heating the tube furnace to 300° C. to vaporize all the single alkali metal atoms in the solid powder, so as to accurately obtain the required amount of single alkali metal atoms for the alkali metal gas chamber.

6. The method for accurately filling a single alkali metal atom into an alkali metal gas chamber according to claim 1, characterized in that: Step 4 includes a vacuum system connected to the tube furnace, and the working vacuum degree reaches 5×10 -6 Pa, vacuum leakage rate up to 1×10 - 8 PaL / S.

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