CN102508375A - Terahertz tunable filter of metal photonic crystal - Google Patents
Terahertz tunable filter of metal photonic crystal Download PDFInfo
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- CN102508375A CN102508375A CN2011103507086A CN201110350708A CN102508375A CN 102508375 A CN102508375 A CN 102508375A CN 2011103507086 A CN2011103507086 A CN 2011103507086A CN 201110350708 A CN201110350708 A CN 201110350708A CN 102508375 A CN102508375 A CN 102508375A
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Abstract
The invention discloses a Terahertz tunable filter device of a metal photonic crystal and a control method thereof. A photonic crystal metal column array is encapsulated in a high-density polyethylene box which is filled with liquid crystals. The pointed angles of the liquid crystal molecules filled around the metal column are changed by controlling voltage, so that the energy band and band clearance position of the metal photonic crystal is changed to control the movement of a filter passband position and realize the function of tunable filtering. As a metal material is adopted to manufacture the photonic crystal, the shortcomings that the passband width is narrowed and the transmission rate is reduced in the tuning process of a medium photonic crystal are conquered; and the turning range of the photonic crystal is greatly extended. As the metal column serves as a special structure of an electrode, so that the distance between the anode and cathode is reduced; the consistency of liquid crystal distribution is improved; the working voltage is reduced and the response time is enhanced. The Terahertz tunable filter of the metal photonic crystal disclosed by the invention has the advantages of wide transmission band width and tunable range, stable passband width and transmission rate in the tuning process, less power consumption and high extinction ratio and is convenient for minimization and integration.
Description
Technical field
The invention belongs to the Terahertz applied technical field, be specifically related to a kind of THz wave tunable optic filter and control method thereof.
Background technology
Terahertz (THz, 1THz=10
12THz) ripple is meant the electromagnetic wave of frequency in 0.1-10THz (corresponding wavelength is 3mm～30 μ m) scope, and this wave band is the crossing domain of electronics and photonics between microwave and light wave.Because its residing specific position in electromagnetic wave spectrum, THz wave has many advantageous characteristic such as perspectivity, security, high s/n ratio, has very important science and using value in spectrum, imaging and field such as communicate by letter.Terahertz function element such as wave filter, switch, beam splitter, the polarizer, phase delay device etc. are important component parts in the Terahertz application system, and wherein terahertz filter is the key core device of Terahertz application system.Wave filter can extract the frequency of operation of needs from the terahertz signal of broadband, and tunable optic filter is controlled the passband position of wave filter, further realizes the controlled transmission to THz wave.
At present, common terahertz filter mainly contains: (1) is based on the terahertz filter of ultra material (metamaterial).Though this type wave filter flexible design is easy to realize that be mostly bandreject filtering, the filtering spectral line is undesirable, chromatic dispersion is bigger, and extinction ratio is low.(2) based on the terahertz filter of one-dimensional medium photonic crystal, this type filter bandwidht is very narrow, is inappropriate for existing broadband Terahertz system.(3) based on the terahertz filter of two-dimensional medium photonic crystal, it is that base material is processed post or hole array with silicon or polymkeric substance, can realize broadband bandpass filtering function.Changeable refractive index material such as filling liquid crystal in this type of wave filter can be realized tuning to wave filter through the refractive index that changes packing material.Yet after the traditional sucrose photonic crystal filled,, cause tuning range very limited because the difference of packing material and the dielectric constant of the base material that constitutes photonic crystal reduces; And cause the passband spectral bandwidth of wave filter to reduce; Transmitance decline [H.Zhang, S.J.Chang et.al, J.Opt.Soc.AmB; 26 (1): 101-106,2009].
In current material, have only High Resistivity Si, high density polyethylene, high conductivity metal (copper, aluminium, silver etc.) can ignore to the absorption loss of Terahertz.Therefore, how to utilize these limited materials, it is big to design tuning range, and the high-performance Terahertz tunable optic filter that pass band width and transmitance are stable is a key technical problem of being badly in need of solution in the Terahertz application system.
Summary of the invention
To the deficiency of above terahertz filter, the object of the present invention is to provide a kind of metal photonic crystal Terahertz tunable optic filter and control method thereof of filling liquid crystal.
The metal photonic crystal tunable optic filter comprises: photonic crystal metal column array, high density polyethylene box, electrode, Terahertz source, liquid crystal.Photonic crystal metal column array package in the high density polyethylene box, filling liquid crystal in the box.The material that photonic crystal metal column array uses is high conductivity metal materials such as copper, aluminium, silver, gold.Its method for making is for forming the metal column array by utilizing coating process to plate one deck on the surface after silicon chip or the moulding of polymkeric substance use MEMS degree of depth photoetching process greater than the thick metal film of 100nm; High 100～500 μ m of metal column; Diameter 40～100 μ m, the adjacent pillars spacing is 100～200 μ m.Above every row photonic crystal metal column, arrange the lead-in wire of polyphone, listing in odd number parallelly connected respectively with even column is positive and negative electrode, and WV is adjustable continuously between 0～5V.The metal column array itself is again the electrode of tuned filter both as photonic crystal.Liquid crystal selects 5CB, E7 etc. to have high birefringence low-loss nematic liquid crystal at terahertz wave band, and double refractive inde is greater than 0.15.Employed Terahertz source is the Terahertz source, broadband that Terahertz photoelectricity lead antenna produces, spectrum composition 0.1-3THz.
The method of work of metal photonic crystal Terahertz tunable optic filter is: through the electrode voltage on the control photonic crystal metal column array; Change the orientation angle that is filled in metal column liquid crystal on every side; Thereby change metal photonic crystal can be with and the mobile of control filters passband position come in the band gap position, the function of realization tuning filtering.When voltage is zero, liquid crystal along axis of a cylinder to distribution; When voltage increases gradually, the liquid crystal orientation angle turns to perpendicular to axis of a cylinder to distribution gradually.Liquid crystal reduces in the refractive index of terahertz wave band gradually in this process, metal photonic crystal can be with and the band gap position is moved to high frequency by low frequency, thereby the passband of wave filter is moved to high frequency, realize tuning filtering.
The invention has the beneficial effects as follows: (1) has adopted metal material to make photonic crystal.Because common metal is very big at the dielectric constant of terahertz wave band; Can be considered the desired electrical conductor; The filling of liquid crystal and the change of its refractive index, what only change metal photonic crystal can be with the position, and does not change bandwidth and spectral transmittance; Overcome the shortcoming that pass band width narrows down, transmitance descends behind the photon dielectric crystal filling liquid crystals such as silicon, high density polyethylene, and improved about one times than the tuning range of the photon dielectric crystal of equivalent constructions parameter.(2) arranged alternate electrode above metal photonic crystal post array, making liquid crystal point to distribution angle can rotate with voltage continuously, thereby realizes the adjustable continuously of wave filter.Than the liquid crystal tuning device of past layout positive and negative electrode in both sides, use photonic crystal metal column itself as electrode, reduce electrode distance, thereby improved the liquid crystal Uniformity of Distribution, reduced WV, improved the response time.
Advantage of the present invention is: this metal photonic crystal tunable optic filter transport tape is roomy, the continuously adjustable wide ranges, and pass band width and transmitance are stable in the tuning process; Loss is little; Extinction ratio is high, is convenient to miniaturization and integrated, satisfies the requirement of Terahertz communication system, spectrum and imaging system.
Description of drawings
Fig. 1 (a) is the schematic three dimensional views of metal photonic crystal tunable optic filter;
Fig. 1 (b) is the electrode and the liquid crystal distribution schematic diagram of metal photonic crystal tunable optic filter;
Fig. 2 is the change curve of electrode liquid crystal orientation angle when applying different voltage;
Fig. 3 (a) is the band structure figure of metal photonic crystal when not applying voltage;
Fig. 3 (b) is the band structure figure of metal photonic crystal when applying 5V voltage;
Fig. 4 is when applying 0V and 5V voltage, the transmission spectral line of metal photonic crystal tunable optic filter;
Fig. 5 (a) is when applying 0V voltage, and frequency is the stable state transmission synoptic diagram of THz wave in the metal photonic crystal tunable optic filter of 1.05THz;
Fig. 5 (b) is when applying 5V voltage, and frequency is the stable state transmission synoptic diagram of THz wave in the metal photonic crystal tunable optic filter of 1.05THz.
Among the figure: metal photonic crystal post 1, high density polyethylene box 2, positive and negative electrode 3, Terahertz wave source 4, liquid crystal 5.
Embodiment
The course of work of the present invention is by near the metal photonic crystal tunable optic filter instance explanation that is operated in the 1THz:
This metal photonic crystal column diameter 80 μ m, intercolumniation 180 μ m, filling liquid crystal E7, device overall dimensions 5mm * 3mm, high 1mm.The broadband terahertz signal of the 0.1～3THz that is sent by photoconductive antenna incides in the metal photonic crystal tunable optic filter, shown in Fig. 1 (a).When electrode voltage was 0, liquid crystal pointed to along the metal column axis and arranges in the device, and angle theta is 0 degree.At this moment, liquid crystal is 1.75 in the refractive index of terahertz wave band, and the band structure of metal photonic crystal is shown in Fig. 3 (a), and the transmission spectrum of wave filter is as shown in Figure 4, and near its passband 1THz is 0.89～1.03THz.When electrode application voltage, the liquid crystal molecule directed in orthogonal in the device as shown in Figure 2 is rotated in the metal column axis direction.The refractive index of liquid crystal can be drawn by following formula:
N wherein
e=1.75, n
0=1.57, n
zBe actual refractive index.Therefore, along with voltage increases, liquid-crystal refractive-index reduces, and being with of metal photonic crystal moved to high frequency, and the passband of wave filter also moves to the high frequency position.When voltage reached 5V, liquid crystal pointed to the metal column axis angle and reaches 90 degree, and like Fig. 3 (b) and shown in Figure 4, the passband position of wave filter finally moves to 0.99-1.14THz to high frequency.It should be noted that in this change procedure, the bandwidth of metal photonic crystal remains unchanged, the spectral line shape of the transmission spectrum of wave filter remains unchanged basically.As shown in Figure 5, to the 1.05THz ripple, THz wave can not pass through wave filter during 0V voltage, and THz wave can well pass through wave filter during 5V, has shown filter function and High Extinction Ratio that device is good.Therefore, this Terahertz tunable optic filter can be realized the continuous tuning of centre frequency from 0.96 to 1.07THz, and its tuning range 110GHz is much larger than the tuning range that is operated near the 60GHz of the silicon photonic crystal terahertz filter 1THz of past bibliographical information.In addition, its 3dB pass band width keeps 150GHz constant, and the passband transmitance remains at more than 95%, and extinction ratio can effectively be controlled the transmission of THz wave greater than 30dB.
Claims (5)
1. metal photonic crystal Terahertz tunable optic filter; It is characterized in that comprising photonic crystal metal column array (1), high density polyethylene box (2), electrode (3), Terahertz source (4), liquid crystal (5); Wherein, Photonic crystal metal column array (1) is packaged in the high density polyethylene box (2), and filling liquid crystal in the box (5) is alternately arranged positive and negative electrode (3) on the photonic crystal metal column array (1).
2. metal photonic crystal Terahertz tunable optic filter according to claim 1; It is characterized in that the material that photonic crystal metal column array (1) uses is high conductivity metal materials such as copper, aluminium, silver, gold; Its method for making is for forming the metal column array by utilizing coating process to plate one deck on the surface after silicon chip or the moulding of polymkeric substance use MEMS degree of depth photoetching process greater than the thick metal film of 100nm; High 100～500 μ m of metal column; Diameter 40～100 μ m, the adjacent pillars spacing is 100～200 μ m.
3. metal photonic crystal Terahertz tunable optic filter according to claim 1; It is characterized in that arranging the lead-in wire of polyphone in every row photonic crystal metal column (1) top; Listing in odd number parallelly connected respectively with even column is positive and negative electrode (3), and WV is adjustable continuously between 0～5V, and the metal column array is both as photonic crystal; Itself is again the electrode of tuned filter, makes positive and negative electrode (3) spacing be not more than 200 μ m.
4. metal photonic crystal Terahertz tunable optic filter according to claim 1, what it is characterized in that in high density polyethylene box (2) filling is to have high birefringence, low-loss nematic liquid crystal (5) at terahertz wave band, double refractive inde is greater than 0.15.
5. tuning methods that uses right 1 described metal photonic crystal Terahertz tunable optic filter; Its characteristic is at the electrode voltage that passes through on the control photonic crystal metal column array; Change the orientation angle that is filled in metal column liquid crystal molecule on every side; Thereby change metal photonic crystal can be with and the mobile of control filters passband position come in the band gap position, the function of realization tuning filtering; When voltage is zero, liquid crystal along axis of a cylinder to distribution; When voltage increases gradually; The liquid crystal orientation angle turns to perpendicular to axis of a cylinder to distribution gradually; Liquid crystal reduces in the refractive index of terahertz wave band gradually in this process; Metal photonic crystal can be with and the band gap position is moved to high frequency by low frequency, thereby the passband of wave filter moves to high frequency, realizes the tuning filtering function.
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Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102866554A (en) * | 2012-10-10 | 2013-01-09 | 南京大学 | Broadband-adjustable terahertz wave plate |
| CN104570205A (en) * | 2014-12-31 | 2015-04-29 | 重庆工商职业学院 | Auto-collimation photonic crystal optical switch based on liquid crystal modulation |
| CN105717675A (en) * | 2016-04-21 | 2016-06-29 | 哈尔滨工业大学 | Preparation method for terahertz waveband electric control liquid crystalline phase shifter based on polymer transparent electrode |
| CN106019648A (en) * | 2016-05-27 | 2016-10-12 | 哈尔滨理工大学 | Filter of tunable terahertz metamaterial and preparation method thereof based on low-voltage-driven liquid crystal material |
| CN106772740A (en) * | 2016-12-02 | 2017-05-31 | 兰州大学 | A kind of photonic crystal filters and its application for thermo-optical cell |
| CN108089251A (en) * | 2018-01-24 | 2018-05-29 | 厦门大学嘉庚学院 | Terahertz wave band quadruple photonic crystal bandstop filter |
| CN108333803A (en) * | 2018-01-23 | 2018-07-27 | 中国计量大学 | A kind of adjustable Terahertz meta-material absorber |
| CN113281929A (en) * | 2021-03-04 | 2021-08-20 | 桂林电子科技大学 | Electrotunable liquid crystal gap plasma structure color filter |
| CN114137658A (en) * | 2021-12-03 | 2022-03-04 | 电子科技大学长三角研究院(湖州) | Low-loss terahertz waveguide of elliptical metal column lattice photonic crystal |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101414029A (en) * | 2007-11-14 | 2009-04-22 | 集美大学 | Two-dimensional hetero-junction photon crystal tunable filter |
| US20100091224A1 (en) * | 2008-10-10 | 2010-04-15 | Samsung Electronics Co., Ltd. | Photonic crystal optical filter, reflective color filter, display apparatus using the reflective color filter, and method of manufacturing the reflective color filter |
| CN201666992U (en) * | 2010-03-12 | 2010-12-08 | 无锡市奥达光电子有限责任公司 | Liquid crystal tunable filter |
-
2011
- 2011-11-09 CN CN2011103507086A patent/CN102508375A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101414029A (en) * | 2007-11-14 | 2009-04-22 | 集美大学 | Two-dimensional hetero-junction photon crystal tunable filter |
| US20100091224A1 (en) * | 2008-10-10 | 2010-04-15 | Samsung Electronics Co., Ltd. | Photonic crystal optical filter, reflective color filter, display apparatus using the reflective color filter, and method of manufacturing the reflective color filter |
| CN201666992U (en) * | 2010-03-12 | 2010-12-08 | 无锡市奥达光电子有限责任公司 | Liquid crystal tunable filter |
Non-Patent Citations (4)
| Title |
|---|
| ZHANG HUI等: "Liquid-crystal-filled photonic crystal for terahertz switch and filter", 《J.OPT.SOC.AM.B》 * |
| 刘启能: "光子晶体多通道可调谐滤波器的理论研究", 《应用光学》 * |
| 刘启能: "可调谐双通道光子晶体滤波器的设计", 《半导体光电》 * |
| 黄婉文等: "太赫兹波导器件研究进展", 《激光与光电子学进展》 * |
Cited By (16)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102866554B (en) * | 2012-10-10 | 2016-04-13 | 南京大学 | The Terahertz wave plate that a kind of wideband is adjustable |
| CN102866554A (en) * | 2012-10-10 | 2013-01-09 | 南京大学 | Broadband-adjustable terahertz wave plate |
| CN104570205A (en) * | 2014-12-31 | 2015-04-29 | 重庆工商职业学院 | Auto-collimation photonic crystal optical switch based on liquid crystal modulation |
| CN105717675B (en) * | 2016-04-21 | 2018-09-11 | 哈尔滨工业大学 | The preparation method of terahertz wave band electrically-controlled liquid crystal phase-shifter based on polymeric transparent electrode |
| CN105717675A (en) * | 2016-04-21 | 2016-06-29 | 哈尔滨工业大学 | Preparation method for terahertz waveband electric control liquid crystalline phase shifter based on polymer transparent electrode |
| CN106019648A (en) * | 2016-05-27 | 2016-10-12 | 哈尔滨理工大学 | Filter of tunable terahertz metamaterial and preparation method thereof based on low-voltage-driven liquid crystal material |
| CN106019648B (en) * | 2016-05-27 | 2019-02-12 | 哈尔滨理工大学 | A kind of tunable Terahertz Meta Materials filter and preparation method thereof based on low voltage drive liquid crystal material |
| CN106772740A (en) * | 2016-12-02 | 2017-05-31 | 兰州大学 | A kind of photonic crystal filters and its application for thermo-optical cell |
| CN108333803A (en) * | 2018-01-23 | 2018-07-27 | 中国计量大学 | A kind of adjustable Terahertz meta-material absorber |
| CN108333803B (en) * | 2018-01-23 | 2020-10-20 | 中国计量大学 | Adjustable terahertz metamaterial absorber |
| CN108089251A (en) * | 2018-01-24 | 2018-05-29 | 厦门大学嘉庚学院 | Terahertz wave band quadruple photonic crystal bandstop filter |
| CN108089251B (en) * | 2018-01-24 | 2023-05-12 | 厦门大学嘉庚学院 | Terahertz wave band quadruple photonic crystal band-stop filter |
| CN113281929A (en) * | 2021-03-04 | 2021-08-20 | 桂林电子科技大学 | Electrotunable liquid crystal gap plasma structure color filter |
| CN113281929B (en) * | 2021-03-04 | 2022-07-12 | 桂林电子科技大学 | Electrotunable liquid crystal gap plasma structure color filter |
| CN114137658A (en) * | 2021-12-03 | 2022-03-04 | 电子科技大学长三角研究院(湖州) | Low-loss terahertz waveguide of elliptical metal column lattice photonic crystal |
| CN114137658B (en) * | 2021-12-03 | 2023-09-12 | 电子科技大学长三角研究院(湖州) | Low-loss terahertz waveguide of elliptic metal column lattice photonic crystal |
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Application publication date: 20120620 |