Optical Tamm state and surface plasmon one-dimensional photonic crystal photoelectric sensor

Abstract

The invention discloses a one-dimensional photonic crystal photoelectric sensor of an optical Tamm state and surface plasmon. The one-dimensional photonic crystal photoelectric sensor comprises a substrate layer, a DBR structure layer and a silver film layer which are connected in sequence. The one-dimensional photonic crystal photoelectric sensor does not need a specific incident angle, the forming condition is relatively simple, the application of a strong coupling system in the fields of sensing, fluorescent light field regulation and the like is realized, the one-dimensional photonic crystal photoelectric sensor can be used for detecting trace samples such as macromolecular solutions and biological reagents, and the sensing performance is greatly improved.

Description

Technical Field

[0001] The present invention belongs to the field of sensors, and in particular relates to a one-dimensional photonic crystal photoelectric sensor of optical Tamm state and surface plasmon. Background Art

[0002] With the continuous development of micro-nanofabrication and laser technology, the interaction between light and matter at the micro-nanoscale has gradually become a new research hotspot. However, the coupling devices used in the past to couple materials and light fields within microcavities are often limited by the complex cavity structure preparation process and harsh device operating conditions, which has hindered the application and development of coupled optoelectronic devices at the micro-nanoscale.

[0003] Currently, Chinese patent publication number CN212180625U discloses an optical sensor based on Tamm-state plasmons. The patent includes a response layer and a distributed Bragg reflector (DBR). The DBR comprises a plurality of alternating first and second dielectric layers, each with a lower refractive index than the second. The response layer is positioned at the end of the DBR where the second dielectric layer is located, with a drainage layer positioned between the response layer and the DBR. This patent effectively improves the sensor's sensitivity by employing a novel response layer and placing a drainage layer between the DBR and the response layer.

[0004] Currently, Chinese patent application publication number CN115165794A discloses an ultrasensitive terahertz liquid sensor based on the optical Tamm-state photon spin Hall effect. The patent comprises an analyte layer, an indium antimonide layer, a near-zero refractive index material layer, and a Bragg reflection structure layer. The analyte layer is the liquid to be measured. An incident linearly polarized light beam (in the terahertz band) is irradiated onto the sensor structure. By measuring the spin shift of the reflected light from the spin Hall effect after the liquid is filled, the type and concentration of the liquid can be detected.

[0005] However, the above-mentioned existing patents have relatively high requirements on the incident angle and the formation conditions are relatively complex. Summary of the Invention

[0006] In order to solve the above technical problems, the technical solutions of the present invention are as follows:

[0007] The one-dimensional photonic crystal photoelectric sensor of optical Tamm state and surface plasmon includes a substrate layer, a DBR structure layer and a silver film layer connected in sequence.

[0008] In a preferred embodiment of the present invention, the thickness of the silver thin film layer is 30 nm.

[0009] In a preferred embodiment of the present invention, the DBR structure layer is a periodic structure composed of two materials with different refractive indices arranged in an alternating manner, and the optical thickness of each layer of material is 1 / 4 of the central reflection wavelength.

[0010] In a preferred embodiment of the present invention, the two materials with different refractive indices of the DBR structure layer include magnesium fluoride and zinc sulfide.

[0011] In a preferred embodiment of the present invention, the DBR structure layer includes a DBR structure of 7 magnesium fluoride layers periodically combined with a zinc sulfide layer.

[0012] In a preferred embodiment of the present invention, the substrate layer is a glass layer.

[0013] In a preferred embodiment of the present invention, the silver thin film layer is formed by electron beam evaporation and magnetron sputtering.

[0014] The beneficial effects of the present invention are:

[0015] 1. No specific incident angle is required, and the formation conditions are relatively simple;

[0016] 2. This structure realizes the application of strong coupling system in the fields of sensing and fluorescence light field control;

[0017] 3. It can detect trace samples such as polymer solutions and biological reagents;

[0018] 4. Greatly improved sensing performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 Schematic diagram of the structure of the one-dimensional photonic crystal photoelectric sensor of optical Tamm state and surface plasmon of the present invention.

[0020] Figure 2 This is the peak value of the silver thin film layer with a thickness of 30 nm simulated by COMSO (multi-physics field simulation software) of the present invention. DETAILED DESCRIPTION

[0021] Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0022] The inventors have discovered that surface plasmons in metal structures, as well as optical Tamm states at the interface between one-dimensional photonic crystals and metal films, exhibit the effects of light field intensity confinement, local field enhancement, and resonant wavelength tunability. By utilizing the properties of these metal optical surface states, they can replace microcavities (optical microcavities, which primarily include geometric morphologies such as microspheres, micropillars, and microrings, are a type of morphology-dependent optical resonant cavity. Light waves within a microcavity undergo total internal reflection at the microcavity interface, generating resonant modes known as whispering gallery modes (WGMs)). This allows the formation of a strongly coupled interaction system with matter in an open environment at the micro- and nanoscale. This strongly coupled system can then be used for applications in sensing and fluorescence light field control.

[0023] On this basis, the present invention discloses a one-dimensional photonic crystal photoelectric sensor of optical Tamm state and surface plasmon. Figure 1 This is a structural diagram of a one-dimensional photonic crystal photoelectric sensor for optical Tamm state and surface plasmon of the present invention, comprising a substrate layer 1, a DBR structure layer 2 and a silver thin film layer 3 connected in sequence.

[0024] In this embodiment, the substrate layer 1 is a glass layer, and the DBR structure layer 2 (i.e., a distributed Bragg reflector) is a periodic structure composed of two materials with different refractive indices arranged in an alternating manner, with the optical thickness of each layer of material being 1 / 4 of the central reflection wavelength. Preferably, the DBR structure layer 2 is a two-layer film with a high refractive index and a low refractive index. The two materials with different refractive indices of the DBR structure layer 2 include magnesium fluoride and zinc sulfide. The DBR structure layer 2 includes a DBR structure consisting of seven magnesium fluoride layers periodically combined with a layer of zinc sulfide.

[0025] In one embodiment, the thickness of the silver thin film layer 3 is 30 nm. The silver thin film layer is formed by electron beam evaporation and magnetron sputtering. Electron beam evaporation and magnetron sputtering are existing technologies and will not be described in detail here. The surface of the coupling device sample can be spin-coated with ethylene glycol solutions of different concentrations to achieve sensor characteristics according to the change in reflectivity. As shown in Table 1 below,

[0026] Table 1 is the data table of optical Tamm state of DBR structure and silver thin film layer structure

[0027] 400nm 500nm 600nm 700nm 800nm 900nm reflection 0.2 0.05 1 1 0.4 0.3 transmission 0.79 0.84 0 0 0.6 0.7 absorb 0.01 0.01 0 0 0 0

[0028] The data in Table 1 show that in the sensor formed by the present invention, when light hits the silver thin film layer 3 and is reflected, its reflectivity reaches 1. The drift of this reflection is the detected sensor signal, and the sensing performance is very good.

[0029] Figure 2This is the peak value of the silver thin film layer with a thickness of 30 nm simulated by comsol (multi-physics field simulation software) in the present invention. Figure 2 The horizontal axis represents the wavelength of light, and the vertical axis represents reflectivity, transmittance, and absorptivity. The blue curve represents a partial reflection curve, the green curve represents the first partial transmission curve, the red curve represents the overall reflection and transmission curve, and the blue-green curve represents the absorption curve. Comparing the peak values ​​for different silver film thicknesses (70nm, 60nm, 50nm, 40nm, 30nm, 20nm, 15nm, and 10nm), it is concluded that when the silver film thickness is 30nm, the peak values ​​of the reflection, transmission, and absorption curves overlap very well, resulting in a better peak value. The light field in the air layer is more sensitive to external changes, and the sensor sensitivity is higher. Therefore, the preferred silver film thickness in the present invention is 30nm.

[0030] Combined with the following Table 2,

[0031] Table 2 is the data table of the combined electric field distribution of the optical Tamm state of the silver thin film layer 30nm+DBR structure

[0032]

[0033] From Table 2, we can see that the electric field distribution in each cycle is very good, the reflection is excellent, and the sensor sensitivity is high.

[0034] The beneficial effects of the present invention are:

[0035] 1. No specific incident angle is required, and the formation conditions are relatively simple;

[0036] 2. This structure realizes the application of strong coupling system in the fields of sensing and fluorescence light field control;

[0037] 3. It can detect trace samples such as polymer solutions and biological reagents;

[0038] 4. Greatly improved sensing performance.

[0039] The above is a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. A one-dimensional photonic crystal photoelectric sensor based on optical Tamm state and surface plasmon, characterized in that: The invention comprises a base layer, a DBR structure layer and a silver thin film layer which are connected in sequence.

2. The one-dimensional photonic crystal photoelectric sensor of optical Tamm state and surface plasmon according to claim 1, characterized in that: The thickness of the silver thin film layer is 30 nm.

3. The one-dimensional photonic crystal photoelectric sensor of optical Tamm state and surface plasmon according to claim 1, characterized in that: The DBR structure layer is a periodic structure composed of two materials with different refractive indices arranged in an alternating manner, and the optical thickness of each layer of material is 1 / 4 of the central reflection wavelength.

4. The one-dimensional photonic crystal photoelectric sensor of optical Tamm state and surface plasmon according to claim 3, characterized in that: The two materials with different refractive indexes in the DBR structure layer include magnesium fluoride and zinc sulfide.

5. The one-dimensional photonic crystal photoelectric sensor of optical Tamm state and surface plasmon according to claim 4, characterized in that: The DBR structure layer includes a DBR structure of seven magnesium fluoride layers periodically combined with a zinc sulfide layer.

6. The one-dimensional photonic crystal photoelectric sensor of optical Tamm state and surface plasmon according to claim 1, characterized in that: The base layer is a glass layer.

7. The one-dimensional photonic crystal photoelectric sensor of optical Tamm state and surface plasmon according to claim 1, characterized in that: The silver thin film layer is formed by electron beam evaporation and magnetron sputtering.

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