阅读说明：本技术 一种基于Tamm态诱导的超宽截止窄带通滤波器 (Ultra-wide cut-off narrow band-pass filter based on Tamm state induction ) 是由 王少伟 刘清权 赵新潮 周兴雷 陆卫 于 2020-05-22 设计创作，主要内容包括：本发明公开一种基于Tamm态诱导的超宽截止窄带通滤波器,器件结构自下而上由衬底、底层一维光子晶体、第一介质层、负介电常数材料层、第二介质层、顶层一维光子晶体组成。当特定波长的光照射在此窄带通滤波器上时,会在负介电常数材料层与光子晶体的交界处激发Tamm等离激元,诱导该波长的光能透过该器件,形成窄带透射,定义窄带透射中心波长为该器件的中心波长,通过调整光子晶体的禁带和反射相位能够灵活地改变中心波长的透射峰位。该器件截止范围可从深紫外到远红外,中心波长从可见到红外可调,并且结构简单、层数少,易与探测器集成。(The invention discloses a super-wide cut-off narrow band-pass filter based on Tamm state induction. When light with a specific wavelength is irradiated on the narrow band-pass filter, Tamm plasmon can be excited at the junction of the negative dielectric constant material layer and the photonic crystal, light energy with the wavelength is induced to penetrate through the device to form narrow-band transmission, the central wavelength of the narrow-band transmission is defined as the central wavelength of the device, and the transmission peak position of the central wavelength can be flexibly changed by adjusting the forbidden band and the reflection phase of the photonic crystal. The device has the advantages of adjustable cut-off range from deep ultraviolet to far infrared, adjustable central wavelength from visible to infrared, simple structure, few layers and easy integration with a detector.)

1. The utility model provides an ultra wide cut-off narrow band-pass filter based on Tamm attitude is induced which characterized in that:

the structure of the ultra-wide cut-off narrow bandpass filter is as follows from bottom to top in sequence: the photonic crystal structure comprises a substrate (1), a bottom one-dimensional photonic crystal (2), a first dielectric layer (3), a negative dielectric constant material layer (4), a second dielectric layer (5) and a top one-dimensional photonic crystal (6);

the bottom layer one-dimensional photonic crystal (2) is a periodic alternating dielectric film with the growth direction vertical to the surface of the substrate, and consists of two or more dielectric materials with different refractive indexes, and the photonic band gap of the bottom layer one-dimensional photonic crystal comprises a narrow band wavelength which is required to be transmitted by the ultra-wide cut-off narrow band-pass filter;

the top layer one-dimensional photonic crystal (6) is a periodic alternating dielectric film with the growth direction vertical to the surface of the substrate, and consists of two or more dielectric materials with different refractive indexes, and the photonic band gap of the top layer one-dimensional photonic crystal comprises a narrow band wavelength which is required to be transmitted by the ultra-wide cut-off narrow band-pass filter;

the thickness of the first medium layer (3) requires the reflection phase of the incident light with the central wavelength on the upper surface of the first medium layer (3)Excitation conditions of Tamm plasmon are satisfied:wherein k is an integer in the formula (I),is the reflection phase of the lower surface of the negative dielectric constant material layer (4);

the thickness of the second dielectric layer (5) requires the reflection phase of the incident light with the central wavelength on the lower surface of the second dielectric layer (5)Excitation conditions of Tamm plasmon are satisfied:wherein k is an integer in the formula (I),is the reflection phase of the upper surface of the negative dielectric constant material layer (4).

2. A ultra-wide cut-off narrow bandpass filter based on Tamm state induction according to claim 1, characterized in that:

the material of the negative dielectric constant material layer (4) adopts metal, alloy, metamaterial or superconducting material, and the thickness interval is [0.01 μm,1 μm ].

3. A ultra-wide cut-off narrow bandpass filter based on Tamm state induction according to claim 1, characterized in that:

the substrate (1) is made of silicon, silicon dioxide, germanium, zinc sulfide, gallium arsenide, indium gallium arsenide, mercury cadmium telluride or colored glass.

4. A ultra-wide cut-off narrow bandpass filter based on Tamm state induction as claimed in claim 1, characterized in that an anti-reflection film for increasing the transmittance of narrow bandpass can be added on the back of the substrate (1).

5. The Tamm state induction-based ultra-wide cut-off narrow bandpass filter according to claim 1, wherein if the upper surface of the bottom one-dimensional photonic crystal (2) reflects the phaseAnd negativeLower surface reflection phase of the dielectric constant material layer (4)Satisfying excitation conditions of Tamm plasmon at center wavelengthWherein k is an integer, the first dielectric layer (3) may be removed.

6. The Tamm state induction-based ultra-wide cut-off narrow bandpass filter according to claim 1, wherein if the lower surface of the top one-dimensional photonic crystal (6) reflects the phaseAnd the upper surface reflection phase of the negative dielectric constant material layer (4)Satisfying excitation conditions of Tamm plasmon at center wavelengthWherein k is an integer, the second dielectric layer (5) may be removed.

Technical Field

The invention relates to the field of optical filters, in particular to an optical narrow bandpass filter.

Background

The optical narrow band-pass filter is a device which can allow light with a single and specified wavelength to pass through, and can cut off light with other wavelengths, and is widely applied to the fields of optical communication, spectrum detection, radiation temperature measurement and the like. For example, space quantum communication needs to detect a laser signal with extremely narrow bandwidth under strong background radiation such as the sun, but because the response range of the detector is wide, noise caused by sunlight in the day is 5 orders of magnitude higher than that at night. When quantum communication is carried out in the daytime, sunlight enters the detector to form great noise interference, and single photons carrying effective information are completely submerged in background noise of the sunlight, so that the conventional air-ground quantum key distribution satellite and the ground can only work in a ground shadow area and are severely limited by weather and astronomical phenomena, and the application of space quantum communication can only be carried out at night under weak moonlight, and is greatly limited. Therefore, a narrow band-pass filter with an ultra-wide cut-off range and a good cut-off effect is urgently needed.

At present, the mainstream filtering devices include a thin film filter, an arrayed waveguide grating filter and a fiber bragg grating filter. The thin film filter has the advantages of simple structure, mature process, good environmental stability, extremely low insertion loss, low polarization loss, flexible configuration, easiness in integration with a detector and the like, so that the thin film filter is the earliest in commercial use and the widest in application range and is the device with the highest occupancy rate in the current market.

The traditional narrow-band thin-film filter is mainly divided into: metal-dielectric fabry-perot filters and all-dielectric fabry-perot filters.

For a metal-dielectric Fabry-Perot filter, the metal-dielectric Fabry-Perot filter has the advantages of extremely wide cut-off band, but due to absorption of metal, the filter has low transmittance and narrow bandwidth (generally, the bandwidth is dozens of nanometers in a near infrared band), and secondary interference peaks appear at integral multiple wave numbers.

Different from a metal-dielectric Fabry-Perot filter, the all-dielectric Fabry-Perot filter adopting the one-dimensional photonic crystal structure to manufacture the reflector has very high transmittance and very narrow bandwidth (less than 1nm in a near infrared band). However, the all-dielectric fabry-perot filter can only have a cut-off effect for a certain wavelength band, and light rays outside the certain wavelength band are transmitted, which is called a bypass band. In most cases, in order to eliminate the side band, a short-wave pass filter and a long-wave pass filter need to be attached on the basis of the film system to respectively eliminate the long-wave side band and the short-wave pass filter, however, the long (short) pass filter needs dozens or even hundreds of film layers to complete, the manufacture is complicated, and the influence of interference peaks is difficult to completely eliminate.

The Tamm plasmon is a photonic surface state presented by professor m.kaliteevski of duren university at the beginning of this century that exists at the interface of a negative dielectric constant material and a photonic crystal. Unlike traditional plasmons, which exist in the forbidden band of photonic crystals, do not need to satisfy the conditions of total internal reflection, and can be excited directly by incident light. By utilizing the characteristics of Tamm plasmons, the ultra-wide cut-off narrow band-pass filter based on Tamm state induction can be manufactured.

Disclosure of Invention

In view of the above, the present invention provides a Tamm state-induced ultra-wide cut-off narrow band-pass filter, which excites Tamm plasmons at an interface between a photonic crystal and a negative dielectric constant material by using incident light with a specific wavelength, so as to induce light transmission of the wavelength, and further, by using a double cut-off effect of a substrate material and the negative dielectric constant material, light except for a central wavelength is cut off, and a cut-off range can be from deep ultraviolet to far infrared.

The structure of the ultra-wide cut-off narrow band-pass filter based on Tamm state induction is sequentially from bottom to top: the photonic crystal structure comprises a substrate 1, a bottom one-dimensional photonic crystal 2, a first dielectric layer 3, a negative dielectric constant material layer 4, a second dielectric layer 5 and a top one-dimensional photonic crystal 6.

The bottom layer one-dimensional photonic crystal 2 is a periodic alternating dielectric film with the growth direction vertical to the surface of the substrate, the composition material of the bottom layer one-dimensional photonic crystal is two or more than two dielectric materials, and the photonic band gap of the bottom layer one-dimensional photonic crystal comprises a narrow-band transmission wavelength which is required to be transmitted by the ultra-wide cut-off narrow-band-pass filter. The structure of the underlying one-dimensional photonic crystal 2 includes, but is not limited to: (HL)ⁿ、(0.5H 1.5L)ⁿ、(3H3L)ⁿ、(HKL)ⁿ、(LKH)ⁿWherein H is a high refractive index material, K is a medium refractive index material, L is a low refractive index material, n is the number of films and n is a positive integer, the optical thickness of the material is one quarter of the center wavelength, and the number in front of the letter represents the change of the material thickness. The materials of the bottom one-dimensional photonic crystal 2 include, but are not limited to: si, Ge, Ta₂O₅、TiO₂、Nb₂O₅、Bi₂O₃、CdS、CdTe、CeO₂、CdSe、Gr₂O₃Diamond, Dy₂O₃、Fe₂O₃、GaAs、HfO₂、Ho₂O₃、InAs、InSb、In₂O₃、PbTe、PbCl₂、PbF₂、Se、Sb₂O₃、Sb₂S₃、SnO₂、Si₃N₄、Te、ZnO、ZnSe、SiO、ZnS、SiO₂、Al₂O₃、AlO_xN_y、AlF₃、BiF₃、BaF₂、CaF₂、CeF₃、CsBr、CsI、Eu₂O₃、Gd₂O₃、LiF、LaF₃、La₂O₃、MgF₂、MgO、NaF、Na₃Al₃F₆、Nd₂O₃、NdF₃、Pr₆O₁₁、Sc₂O₃、SrF₂、SmF₃、Sm₂O₃、ThF₄、YbF₃、Y₂O₃、ZrO₂。

The top layer one-dimensional photonic crystal 6 is a periodic alternating dielectric film with the growth direction vertical to the surface of the substrate, the composition material of the top layer one-dimensional photonic crystal is two or more than two dielectric materials, and the photonic band gap of the top layer one-dimensional photonic crystal comprises a narrow-band transmission wavelength which is required to be transmitted by the ultra-wide cut-off narrow-band-pass filter. The structure of the top one-dimensional photonic crystal 6 includes, but is not limited to: (HL)ⁿ、(0.5H 1.5L)ⁿ、(3H3L)ⁿ、(HKL)ⁿ、(LKH)ⁿWherein H is a high refractive index material, K is a medium refractive index material, and L is a low refractive indexThe material is prepared by the following steps of (1) preparing a material, wherein n is the number of film layers and a positive integer, the optical thickness of the material is one quarter of the central wavelength, and the number in front of the letter represents the change of the thickness of the material. The materials of the top one-dimensional photonic crystal 6 include, but are not limited to: si, Ge, Ta₂O₅、TiO₂、Nb₂O₅、Bi₂O₃、CdS、CdTe、CeO₂、CdSe、Gr₂O₃Diamond, Dy₂O₃、Fe₂O₃、GaAs、HfO₂、Ho₂O₃、InAs、InSb、In₂O₃、PbTe、PbCl₂、PbF₂、Se、Sb₂O₃、Sb₂S₃、SnO₂、Si₃N₄、Te、ZnO、ZnSe、SiO、ZnS、SiO₂、Al₂O₃、AlO_xN_y、AlF₃、BiF₃、BaF₂、CaF₂、CeF₃、CsBr、CsI、Eu₂O₃、Gd₂O₃、LiF、LaF₃、La₂O₃、MgF₂、MgO、NaF、Na₃Al₃F₆、Nd₂O₃、NdF₃、Pr₆O₁₁、Sc₂O₃、SrF₂、SmF₃、Sm₂O₃、ThF₄、YbF₃、Y₂O₃、ZrO₂。

The first dielectric layer 3 is made of a dielectric material and is used for adjusting the reflection phase of the upper surface of the bottom one-dimensional photonic crystal 2 so as to meet the condition that incident light with central wavelength excites Tamm plasmon at the interface of the first dielectric layer 3 and the negative dielectric constant material layer 4, namelyWhereinIs the phase of the reflection of the upper surface of the first dielectric layer 3,is the reflection phase of the lower surface of the negative dielectric constant material layer 4, and k is an integer. The materials of the first dielectric layer 3 include but are not limited to: si, Ge, Ta₂O₅、TiO₂、Nb₂O₅、Bi₂O₃、CdS、CdTe、CeO₂、CdSe、Gr₂O₃Diamond, Dy₂O₃、Fe₂O₃、GaAs、HfO₂、Ho₂O₃、InAs、InSb、In₂O₃、PbTe、PbCl₂、PbF₂、Se、Sb₂O₃、Sb₂S₃、SnO₂、Si₃N₄、Te、ZnO、ZnSe、SiO、ZnS、SiO₂、Al₂O₃、AlO_xN_y、AlF₃、BiF₃、BaF₂、CaF₂、CeF₃、CsBr、CsI、Eu₂O₃、Gd₂O₃、LiF、LaF₃、La₂O₃、MgF₂、MgO、NaF、Na₃Al₃F₆、Nd₂O₃、NdF₃、Pr₆O₁₁、Sc₂O₃、SrF₂、SmF₃、Sm₂O₃、ThF₄、YbF₃、Y₂O₃、ZrO₂。

The second dielectric layer 5 is made of a dielectric material and is used for adjusting the reflection phase of the lower surface of the top one-dimensional photonic crystal 6 so as to meet the condition that incident light with central wavelength excites Tamm plasmon at the interface of the second dielectric layer 5 and the negative dielectric constant material layer 4, namelyWhereinIs the phase of the reflection of the upper surface of the second dielectric layer 5,is a negative dielectric constantThe material layer 4 has a reflection phase on its upper surface, k being an integer. The materials of the second dielectric layer 5 include but are not limited to: si, Ge, Ta₂O₅、TiO₂、Nb₂O₅、Bi₂O₃、CdS、CdTe、CeO₂、CdSe、Gr₂O₃Diamond, Dy₂O₃、Fe₂O₃、GaAs、HfO₂、Ho₂O₃、InAs、InSb、In₂O₃、PbTe、PbCl₂、PbF₂、Se、Sb₂O₃、Sb₂S₃、SnO₂、Si₃N₄、Te、ZnO、ZnSe、SiO、ZnS、SiO₂、Al₂O₃、AlO_xN_y、AlF₃、BiF₃、BaF₂、CaF₂、CeF₃、CsBr、CsI、Eu₂O₃、Gd₂O₃、LiF、LaF₃、La₂O₃、MgF₂、MgO、NaF、Na₃Al₃F₆、Nd₂O₃、NdF₃、Pr₆O₁₁、Sc₂O₃、SrF₂、SmF₃、Sm₂O₃、ThF₄、YbF₃、Y₂O₃、ZrO₂。

The layer of negative dielectric constant material 4 is configured to block the passage of low energy photons, including the center wavelength, and is selected from the group consisting of: metals, alloys, metamaterials, superconducting materials. The thickness interval is [0.01 μm,1 μm ].

The substrate 1 is used to block the high-energy photons that the negative dielectric constant material layer 4 cannot cut off from passing through, and the selected materials include but are not limited to: silicon, silicon dioxide, germanium, zinc sulfide, gallium arsenide, indium gallium arsenic, mercury cadmium telluride and colored glass.

Optionally, an antireflection film is added on the back surface of the substrate 1 to improve the narrow-band transmittance.

Alternatively, if the upper surface of the bottom one-dimensional photonic crystal 2 reflects the phaseAnd the lower surface reflection phase of the negative dielectric constant material layer 4Satisfying Tamm plasmon forming conditions at a center wavelengthWhere n is an integer, the first dielectric layer 3 may be removed.

Optionally, if the lower surface of the top one-dimensional photonic crystal 6 reflects the phaseAnd the upper surface reflection phase of the negative dielectric constant material layer 4Satisfying Tamm plasmon forming conditions at a center wavelengthWhere n is an integer, the second dielectric layer 5 may be eliminated.

The invention has the following advantages:

1. the ultra-wide cut-off band is provided, and the cut-off band width can be from deep ultraviolet to far infrared.

2. The application range is wide, and the infrared band is applicable to short, medium and long wave bands.

3. Has narrow transmission bandwidth of pass band and bandwidth within 10nm in near infrared band.

4. Compared with a Fabry-Perot filter, the peak shape of the filter is closer to a rectangular wave, and the energy utilization rate in a passband is higher.

5. Simple structure, few layers, thin total thickness and easy integration with the detector.

The following further description is made in conjunction with the accompanying drawings and the detailed description.

Drawings

Fig. 1 is a schematic structural diagram of a Tamm state induced ultra-wide cut-off narrow bandpass filter of the invention.

Fig. 2 is a schematic structural diagram of a Tamm state induced ultra-wide cut-off narrow bandpass filter in embodiment 1 of the present invention.

Fig. 3 is the transmission spectrum of the ultra-wide cut-off narrow bandpass filter of embodiment 1 of the invention.

Fig. 4 is a schematic structural diagram of a Tamm state induced ultra-wide cut-off narrow bandpass filter in embodiment 2 of the present invention.

Fig. 5 is the transmission spectrum of the ultra-wide cut-off narrow bandpass filter of embodiment 2 of the invention.

Fig. 6 is a schematic structural diagram of a Tamm state induced ultra-wide cut-off narrow bandpass filter in embodiment 3 of the present invention.

Fig. 7 is the transmission spectrum of the ultra-wide cut-off narrow bandpass filter of embodiment 3 of the invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some embodiments, but not all embodiments, of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.