Alkali long-wave laser with photovoltaic energy recovery

Abstract

The application relates to an alkali metal long-wave laser with a photovoltaic energy recovery device, which comprises a pumping source, an alkali metal pool and a photovoltaic energy recovery device; the pumping source emits pumping light which enters the alkali metal pool and acts on alkali metal vapor in the alkali metal pool to cause the alkali metal vapor to generate long-wave laser and short-wave fluorescence; the long-wave laser and the short-wave fluorescence are output from the alkali metal pool, the long-wave laser is used by a user, the short-wave fluorescence irradiates the photovoltaic energy recovery device, the photovoltaic energy recovery device converts light energy of the short-wave fluorescence into electric energy for recycling, and part of driving power is provided for the pumping source. Compared with other alkali metal long-wave lasers, the alkali metal long-wave laser with the photovoltaic energy recovery device can reduce energy dissipation and waste of short-wave fluorescence emitted by alkali metal vapor, and improve the overall energy conversion efficiency of the alkali metal long-wave laser.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of lasers, and particularly relates to an alkali metal long-wave laser with photovoltaic energy recovery. BACKGROUND

[0002] Alkali metal atoms have abundant energy level transitions, among which there are a large number of energy level transitions with resonance wavelengths in the long-wave light band, such as mid-infrared light, far-infrared light, terahertz light, and even microwave band. Therefore, the particle number inversion effect, stimulated electronic Raman scattering, and stimulated super Raman scattering of the above energy level transitions can be used to make long-wave lasers. Of course, the laser here is a practical concept, which means that it can output a collimated monochromatic light beam similar to a laser. There are some literature reports and patent disclosures of optically pumped alkali metal long-wave lasers based on the above principles, such as a system described in the literature (“Stimulated electronic Raman scattering in Cs vapour: a simple tunable laser system for the 2.7 to 3.5μm region”, Optical and Quantum Electronics 9 (1977) 509-518.). Blue laser is used to irradiate cesium vapor to obtain a 2.67-3.47 μm mid-infrared collimated light beam, and the photon conversion efficiency can reach 50%. Recently, a patent (ZL201810344885.5, “A cesium terahertz collimated light source device and system”) discloses an alkali metal-based terahertz laser source. A big disadvantage of the above long-wave laser system is that the light-light energy conversion rate is very low. Although the light-light conversion quantum efficiency can be high, when a short-wave photon is converted into a long-wave photon, most of the energy of the short-wave photon is ultimately diffused in all directions in the form of short-wave spontaneous emission fluorescence. Therefore, the energy utilization efficiency of the above alkali metal long-wave laser is very low. SUMMARY

[0003] To solve the above technical problems, the application provides an alkali metal long-wave laser with photovoltaic energy recovery. By providing a photovoltaic energy recovery device, such as a solar panel, for the alkali metal long-wave laser, the short-wave spontaneous emission fluorescence diffused in the alkali metal vapor of the alkali metal long-wave laser can be absorbed, so as to convert the energy of the short-wave spontaneous emission fluorescence into electrical energy. These electrical energy can be stored or reused, thereby realizing an energy recovery and utilization cycle and improving the energy efficiency of the alkali metal long-wave laser.

[0004] In order to achieve the above purpose, the technical scheme of the application is as follows:

[0005] The alkali metal long-wave laser with the photovoltaic energy recovery device comprises a pump source, an alkali metal pool and a photovoltaic energy recovery device.

[0006] The alkali metal long-wave laser with the photovoltaic energy recovery device comprises a pump source, an alkali metal pool and a photovoltaic energy recovery device.

[0007] The alkali metal long-wave laser with the photovoltaic energy recovery device comprises a pump source, an alkali metal pool and a photovoltaic energy recovery device.

[0008] The alkali metal long-wave laser with the photovoltaic energy recovery device comprises a pump source, an alkali metal pool and a photovoltaic energy recovery device.

[0009] The alkali metal long-wave laser with the photovoltaic energy recovery device comprises a pump source, an alkali metal pool and a photovoltaic energy recovery device.

[0010] The alkali metal long-wave laser with the photovoltaic energy recovery device comprises a pump source, an alkali metal pool and a photovoltaic energy recovery device.

[0011] The alkali metal long-wave laser with the photovoltaic energy recovery device comprises a pump source, an alkali metal pool and a photovoltaic energy recovery device.

[0012] The alkali metal long-wave laser with the photovoltaic energy recovery device comprises a pump source, an alkali metal pool and a photovoltaic energy recovery device.

[0013] In summary, the alkali metal long-wave laser with photovoltaic energy recovery has the following advantages: the pump source emits pump light under the driving of electric energy; the pump light acts on the alkali metal vapor to generate long-wave laser and short-wave fluorescent light; the long-wave laser output is used by the user; the short-wave fluorescent light illuminates the photovoltaic energy recovery device; the photovoltaic energy recovery device converts the light energy of the short-wave fluorescent light into electric energy, thereby realizing energy recovery; the recovered electric energy can be used to drive the pump source, thereby greatly improving the energy conversion efficiency of electric energy to long-wave laser; the alkali metal long-wave laser with the photovoltaic energy recovery device can be developed into a laser with high output power and high electro-optical efficiency; the efficiency of a silicon solar cell panel can reach 10%, and in a laboratory, the efficiency can reach 20-30%, and there is a large space for further improvement; the absorption and utilization wavelength of the silicon solar cell panel is about 300-1000 nanometers, and the long-wave laser of the alkali metal element vapor can be matched with the long-wave laser of the alkali metal element vapor to realize short-wave fluorescent energy recovery; in addition, there are many other types of solar cell panels in development, which will provide more flexible component matching freedom for the alkali metal long-wave laser with photovoltaic energy recovery.

[0014] The alkali metal long-wave laser with photovoltaic energy recovery has the following advantages:

[0015] Compared with other alkali metal long-wave lasers, the alkali metal long-wave laser with photovoltaic energy recovery can reduce the energy dissipation and waste of short-wave fluorescent light emitted by the alkali metal vapor, and improve the overall energy conversion efficiency of the alkali metal long-wave laser. BRIEF DESCRIPTION OF DRAWINGS

[0016] In order to more clearly illustrate the embodiments of the present application or the technical solutions of the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0017] Figure 1 The device diagram of embodiment 1 of the present application;

[0018] Figure 2 The device diagram of embodiment 3 of the present application.

[0019] In the figure: 1: pump source; 2: pump light; 3: alkali metal pool; 4: long-wave laser; 5: short-wave fluorescent light; 6: photovoltaic energy recovery device; 7-1: rear cavity mirror; 7-2: front cavity mirror. DETAILED DESCRIPTION

[0020] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings:

[0021] Example 1

[0022] A cesium mid-infrared laser with a photovoltaic energy recovery device, such as Figure 1 As shown, during operation, the alkali metal pool 3 is filled with metallic cesium and heated to maintain an overall temperature between 100-300℃, thereby generating uniform saturated cesium vapor within the pool. No other gases are contained in the alkali metal pool 3. The pump source 1 is a pulsed or continuous laser, such as a nanosecond pulsed dye laser, a pulsed optical parametric oscillator, or a continuous-wave semiconductor laser configured with a frequency-doubled crystal as the light source. The overall driving energy for the pump source 1 is electrical energy. The wavelength (vacuum wavelength) of the pump light 2 satisfies the following condition: its photon energy is equivalent to the transition from the ground state to a virtual energy level of a resonant cesium atom, with the virtual energy level located at 7P. 3 / 2 Or 7P 1 / 2 Near the energy level, i.e., near-resonance cesium atom 6S in the pump light. 1 / 2 →7P 3 / 2 Transition (approximately 455 nm), or near-resonance cesium atom 6S 1 / 2 →7P 1 / 2 The specific deviation from resonance at the transition (approximately 459 nm) depends on the instantaneous power density of pump light 2. For nanosecond pulsed pump source 1, the instantaneous power of pump light 2 is relatively high, so its wavenumber deviation from resonance can reach 200 cm⁻¹. -1 The above describes the process where pump light 2 irradiates cesium vapor in an alkali metal cell 3, causing stimulated electron Raman scattering and generating a long-wavelength laser 4 in the mid-infrared band. The long-wavelength laser 4 is characterized by its photon energy approximately resonating with 7P. 3 / 2 →7S 1 / 2 Or 7P 1 / 2 →7S 1 / 2 The transition, with a wavelength of approximately 2.9 μm or 3.1 μm, originates from the alkali metal cell 3 and is available to the user. Simultaneously, a large number of cesium atoms arrive at the 7S phase. 1 / 2 Energy level; further, 7S 1 / 2 Cesium atoms in the energy level undergo a lower energy level transition, emitting spontaneous emission. Since a lower energy level transition necessarily involves the 6P atom... 3 / 2 Or 6P 1 / 2 The energy level then radiatively transitions back to the ground state 6S from this second energy level. 1 / 2 Therefore, the cesium vapor in the alkali metal cell 3, illuminated by pump light 2, will give short-wavelength fluorescence 5, characterized by its photon energy resonating with cesium 6P. 3 / 2 →6S 1 / 2 Energy level transition (approximately 852nm), or 6P 1 / 2→6S 1 / 2 The energy level transition (about 895nm); the short-wave fluorescent light 5 irradiation photovoltaic energy recovery device 6 with about 852nm or 895nm, the photovoltaic energy recovery device 6 is a silicon solar panel, which converts the light energy of the short-wave fluorescent light 5 into electrical energy, and the electrical energy is regulated by the voltage and current control circuit to charge a storage battery for later use of the electrical energy; the electrical energy can also be regulated by the voltage and current control circuit to meet part of the power supply of the pump source 1.

[0023] By converting the short-wave fluorescent light 5 into electrical energy, the light energy carried by the short-wave fluorescent light 5 is prevented from being dissipated and wasted, thereby greatly improving the energy utilization efficiency of the cesium mid-infrared laser, such as the electro-optical conversion efficiency.

[0024] Example 2

[0025] A cesium terahertz laser with a photovoltaic energy recovery device, the structure still refers to Figure 1 , the difference is that it refers to the setting of the patent (ZL 201810344885.5), the pump source is a combined laser source, which can emit a double-color coaxial pump light 2 of near-resonant cesium 6S 1 / 2 →6P 3 / 2 and near-resonant 6P 3 / 2 →11D 5 / 2 transition; the alkali metal cell 3 contains cesium vapor; the pump light 2 acts on the cesium vapor in the alkali metal cell 3, inducing stimulated Raman scattering or stimulated super Raman scattering phenomenon, producing a terahertz frequency long-wave laser 4 of near-resonant cesium 11D 5 / 2 →12P 3 / 2 transition, the terahertz frequency is about 1THz, and when the wavelength of the pump light 2 is fine-tuned, it shows a certain tunability of the terahertz frequency, at the same time, a large number of cesium atoms reach the 12P 3 / 2 energy level; the long-wave laser 4 is output from the alkali metal cell 3 for user use; when the cesium atoms in the 12P 3 / 2 energy level transition to the ground state, the following transition steps are included to give the corresponding wavelength of the short-wave fluorescent light 5: 12P 3 / 2 →6S 1 / 2 (about 335nm), 12S 1 / 2 →6P 3 / 2 (about 558nm), 12S 1 / 2 →6P 1 / 2 (about 541nm), 6P 3 / 2 →6S 1 / 2 (about 852nm), 6P 1 / 2 →6S 1 / 2(Approximately 895nm) Short-wave fluorescence 5 containing these wavelengths reaches photovoltaic energy recovery device 6, which is a silicon solar panel that converts the light energy of short-wave fluorescence 5 into electrical energy. The electrical energy is regulated by voltage and current control circuits to charge a battery for future use. The electrical energy can also be regulated by voltage and current control circuits to meet part of the power supply of pump source 1.

[0026] By converting short-wavelength fluorescence 5 into electrical energy, the light energy carried by short-wavelength fluorescence 5 is prevented from being dissipated and wasted, thereby greatly improving the energy utilization efficiency of cesium mid-infrared lasers, such as electro-optical conversion efficiency.

[0027] Example 3

[0028] A cesium terahertz laser with a photovoltaic energy recovery device and a terahertz resonant cavity, the structure of which is as follows: Figure 2 As shown, its working physical principle is similar to that of Example 2; detailed description follows: The pump source is a combined laser source that can emit precise resonant cesium 6S. 1 / 2 →6P 3 / 2 and precise resonance 6P 3 / 2 →11D 5 / 2 The two-color coaxial pump light 2 causes the transition; the alkali metal cell 3 contains cesium vapor; the rear cavity mirror 7-1 and the front cavity mirror 7-2 form a terahertz laser resonator; the pump light 2 acts on the cesium vapor in the alkali metal cell 3, inducing the ground-state cesium atoms to transition to 6P. 3 / 2 Then it jumped to 11D 5 / 2 Energy level, due to the 12P below 3 / 2 Since the energy level is empty, a population inversion state is formed. Under the resonance of the cavity mode of the terahertz laser resonator composed of the rear cavity mirror 7-1 and the front cavity mirror 7-2, 11D is generated. 5 / 2 →12P 3 / 2 Terahertz laser emission at the resonant frequency, i.e., long-wavelength laser 4, has a frequency of approximately 1.06 THz. Simultaneously, a large number of cesium atoms reach 12P. 3 / 2 Energy level; long-wavelength laser 4 is output from the front cavity mirror 7-2 for user use; at 12P 3 / 2 When a cesium atom transitions from an energy level to the ground state, the following transition steps are involved, giving the corresponding wavelength of short-wavelength fluorescence 5: 12P 3 / 2 →6S 1 / 2 (Approximately 335nm), 12S 1 / 2 →6P 3 / 2 (Approximately 558nm), 12S 1 / 2 →6P 1 / 2 (Approximately 541nm), 6P 3 / 2 →6S 1 / 2 (Approximately 852nm), 6P 1 / 2 →6S 1 / 2(Approximately 895nm) Short-wave fluorescence 5 containing these wavelengths reaches photovoltaic energy recovery device 6, which is a silicon solar panel that converts the light energy of short-wave fluorescence 5 into electrical energy. The electrical energy is regulated by voltage and current control circuits to charge a battery for future use. The electrical energy can also be regulated by voltage and current control circuits to meet part of the power supply of pump source 1.

[0029] By converting short-wavelength fluorescence 5 into electrical energy, the light energy carried by short-wavelength fluorescence 5 is prevented from being dissipated and wasted, thereby greatly improving the energy utilization efficiency of cesium mid-infrared lasers, such as electro-optical conversion efficiency.

[0030] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. An alkali metal long-wavelength laser with a photovoltaic energy recovery device, characterized in that, The laser includes a pump source, an alkali metal cell, and a photovoltaic energy recovery device. The alkali metal cell contains alkali metal vapor, which is composed of alkali metal atoms. The pump source emits pump light, which enters the alkali metal cell and acts on the alkali metal vapor, causing the alkali metal vapor to generate long-wavelength laser and short-wavelength fluorescence. The long-wavelength laser and short-wavelength fluorescence are output from the alkali metal cell. The short-wavelength fluorescence irradiates the photovoltaic energy recovery device, which converts the light energy of the short-wavelength fluorescence into electrical energy, thereby realizing the recovery of the energy of the short-wavelength fluorescence.

2. The alkali metal long-wavelength laser with photovoltaic energy recovery according to claim 1, characterized in that, Long-wavelength lasers generated by alkali metal vapors are produced by stimulated emission based on population inversion of alkali metal atoms, stimulated electron Raman scattering, or stimulated super Raman scattering.

3. The alkali metal long-wavelength laser with photovoltaic energy recovery according to claim 1, characterized in that, Short-wave fluorescence is generated by spontaneous energy level transitions of alkali metal atoms in alkali metal vapor.

4. The alkali metal long-wavelength laser with photovoltaic energy recovery according to claim 1, characterized in that, The photovoltaic energy recovery device is a solar panel.

5. An alkali metal long-wavelength laser with photovoltaic energy recovery according to claim 1, characterized in that, Long-wavelength lasers are collimated beams in the terahertz, far-infrared, mid-infrared, and near-infrared bands; short-wavelength fluorescence is fluorescence in the near-infrared, visible, and near-ultraviolet bands.

6. An alkali metal long-wavelength laser with photovoltaic energy recovery according to claim 1, characterized in that, The laser also includes a front cavity mirror and a rear cavity mirror, which are arranged opposite each other to form a laser resonant cavity, and an alkali metal pool is located between the front cavity mirror and the rear cavity mirror.

7. An alkali metal long-wavelength laser with photovoltaic energy recovery according to claim 1, characterized in that, Alkali metals in alkali metal vapor include lithium, sodium, potassium, rubidium, and cesium.

8. An application of the alkali metal long-wavelength laser with photovoltaic energy recovery as described in any one of claims 1-7.

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