WO2022045970A1 - Nanoantenne plasmonique, réseaux de capteurs à nanoantenne plasmonique, et méthode associée - Google Patents

Nanoantenne plasmonique, réseaux de capteurs à nanoantenne plasmonique, et méthode associée Download PDF

Info

Publication number
WO2022045970A1
WO2022045970A1 PCT/SG2021/050487 SG2021050487W WO2022045970A1 WO 2022045970 A1 WO2022045970 A1 WO 2022045970A1 SG 2021050487 W SG2021050487 W SG 2021050487W WO 2022045970 A1 WO2022045970 A1 WO 2022045970A1
Authority
WO
WIPO (PCT)
Prior art keywords
plasmonic
end portion
plasmonic nanoantenna
nanoantenna
sensor array
Prior art date
Application number
PCT/SG2021/050487
Other languages
English (en)
Inventor
Zhihao REN
Chengkuo Lee
Original Assignee
National University Of Singapore
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by National University Of Singapore filed Critical National University Of Singapore
Publication of WO2022045970A1 publication Critical patent/WO2022045970A1/fr

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
    • G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
    • G01N21/25—Colour; Spectral properties, i.e. comparison of effect of material on the light at two or more different wavelengths or wavelength bands
    • G01N21/31—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry
    • G01N21/35—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry using infrared light
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B1/00—Optical elements characterised by the material of which they are made; Optical coatings for optical elements
    • G02B1/002—Optical elements characterised by the material of which they are made; Optical coatings for optical elements made of materials engineered to provide properties not available in nature, e.g. metamaterials
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B82—NANOTECHNOLOGY
    • B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
    • B82Y15/00—Nanotechnology for interacting, sensing or actuating, e.g. quantum dots as markers in protein assays or molecular motors
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B82—NANOTECHNOLOGY
    • B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
    • B82Y20/00—Nanooptics, e.g. quantum optics or photonic crystals
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
    • G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
    • G01N21/55—Specular reflectivity
    • G01N21/552—Attenuated total reflection
    • G01N21/553—Attenuated total reflection and using surface plasmons
    • G01N21/554—Attenuated total reflection and using surface plasmons detecting the surface plasmon resonance of nanostructured metals, e.g. localised surface plasmon resonance

Definitions

  • the present application relates to plasmonic nanoantennas, and plasmonic nanoantenna sensor arrays. More specifically, the present application relates to plasmonic nanoantenna sensor arrays for sensing molecular vibrations.
  • Molecular identification of gas, liquid, and biomolecules is a fundamental requirement for various applications such as environmental monitoring, healthcare, clinical diagnosis, and biological screening.
  • An efficient approach to identify molecules is in-situ detection of the chemical structures of the molecules in a label-free and non-destructive manner with fast response time and high sensitivity.
  • Optical approaches are suitable for molecule screening in life science since it allows for remote, real-time, and sensitive detection with the development of microscopy technology.
  • MIR Mid-infrared
  • IR spectroscopy offers a solution for non-invasive, non-destructive, label-free, and real-time recognition and monitoring of molecules, especially in the mixture.
  • conventional IR spectroscopy technology is limited by the large optical path ( ⁇ mm to ⁇ cm) due to weak light-matter interaction in MIR, hindering the sensing performance compared with other optical probes technologies such as Raman, fluorescent, and refractometry.
  • Plasmonic nanoantennas enable enhanced electromagnetic nearfield to perform advanced sensing platforms called surface enhanced infrared absorption (SEIRA) spectroscopy by inducing plasmon-phonon interaction in the midinfrared (mid- IR) region, which holds most of the molecular (vibrations) fingerprints absorption peaks.
  • SEIRA surface enhanced infrared absorption
  • the mid-IR fingerprints provide specific identification information of different types of chemical stretches, bends, wags, rocks and twists in molecular structures.
  • plasmonic sensors Compared to traditional optical sensors leveraging the mid-IR fingerprints, plasmonic sensors have the advantages of compact size, fast response time, compatibility for nano integration, which bring the potential for the wearable Internet of Things (loT) sensor applications such as environmental monitoring, healthcare, and clinical diagnostics.
  • LoT wearable Internet of Things
  • PNA plasmonic nanoantennas
  • TCMT temporal coupled-mode theory
  • the physics behind the plasmonic molecule sensor is the plasmon-phonon interaction.
  • EIT electromagnetic induced transparent
  • EIA electromagnetic induced absorption
  • Fano-like resonance in the resonance spectrum.
  • PNA also serves as an ultra-sensitive refractometry sensor to capture the refractive index of analytes by wavelength shifts (e.g., colour change in visible light), which carries the information of physical properties of molecules.
  • PNA has a drawback of limited operation bandwidth because the coupling effect is significant only when the resonance of plasmon and phonon are closely matched.
  • a plasmonic nanoantenna including a main arm having a first finite length defined by a first main arm end portion and a second main arm end portion, and a secondary arm having a second finite length defined by a first secondary arm end portion and a second secondary arm end portion.
  • the plasmonic nanoantenna also includes an intermediate arm arranged to be connected to the second main arm end portion and the second secondary arm end portion.
  • the first main arm end portion and the first secondary arm end portion are arranged to extend in a same direction, and the first finite length is longer than the second finite length.
  • the plasmonic nanoantenna of the first aspect has very high sensitivity with improved detection limits of molecules at ultra-low concentrations. More specifically, a PMMA thin film having a thickness of 20 nm is detectable with a sensitivity of at least 0.6 at a detection wavelength of 5.7 pm.
  • first finite length and the second finite length may differ by between 200 nm to 2000 nm.
  • the first finite length may be between 400 nm to 2500 nm.
  • the second finite length may be between 200 nm to 1100 nm.
  • the intermediate arm may have a third finite length between 200 nm to 800 nm.
  • main arm, the secondary arm, and the intermediate arm may have respective widths between 100 nm and 400 nm.
  • the main arm, the secondary arm, and the intermediate arm may have respective heights between 10 nm and 150 nm.
  • the main arm, the secondary arm, and the intermediate arm may be formed from a material selected from gold, aluminium, molybdenum, graphene, and a composite made of a silicon nitride layer sandwiched between silver and gold.
  • the main arm, the secondary arm, and the intermediate arm may be disposed on an infrared light-permeable substrate.
  • the infrared light-permeable substrate may be selected from CaF2, BaF2, MgF2, ZnS, ZnSe, sapphire and quartz.
  • a PMMA thin film having a thickness of 20 nm may be detectable with a sensitivity of at least 0.6 at a detection wavelength of 5.7 pm.
  • the plasmonic nanoantenna may have a resonance wavelength within the range of 2 pm to 20 pm.
  • a plasmonic nanoantenna sensor array for sensing a molecular vibration.
  • the plasmonic nanoantenna sensor array includes an infrared light-permeable substrate having a surface, and a plurality of pixels arranged on the surface.
  • Each pixel includes an array of plasmonic nanoantennas.
  • Each plasmonic nanoantenna has a main arm having a first finite length defined by a first main arm end portion and a second main arm end portion, and a secondary arm having a second finite length defined by a first secondary arm end portion and a second secondary arm end portion.
  • the plasmonic nanoantenna further includes an intermediate arm arranged to be connected to the second main arm end portion and the second secondary arm end portion.
  • the first main arm end portion and the first secondary arm end portion are arranged to extend in a same direction, and the first finite length is longer than the second finite length.
  • the plasmonic nanoantenna sensor array may have a resonance bandwidth of at least 1 .5 pm in the mid-infrared region.
  • the first finite length of respective main arms of the plasmonic nanoantennas may be of the same length within the respective pixels, but differs in length between the respective pixels
  • the second finite length of respective secondary arms of the plasmonic nanoantennas may be of the same length within the respective pixels, but differs in length between the respective pixels.
  • the respective pixels may have different resonance wavelengths within a range of 2 pm to 20 pm.
  • the first finite length and the second finite length may vary within the respective pixels.
  • a PMMA thin film having a thickness of 20 nm may be detectable with a sensitivity of at least 0.6 at a detection wavelength of 5.7 pm.
  • a method of detecting a molecule includes (i) contacting a sample containing the molecule with a plasmonic nanoantenna sensor array including an infrared light-permeable substrate having a surface, and a plurality of pixels arranged on the surface. Each pixel includes an array of plasmonic nanoantennas.
  • Each plasmonic nanoantenna has a main arm having a first finite length defined by a first main arm end portion and a second main arm end portion, and a secondary arm having a second finite length defined by a first secondary arm end portion and a second secondary arm end portion.
  • the plasmonic nanoantenna also includes an intermediate arm arranged to be connected to the second main arm end portion and the second secondary arm end portion.
  • the first main arm end portion and the first secondary arm end portion are arranged to extend in a same direction, and the first finite length is longer than the second finite length.
  • the method also includes (ii) illuminating the plasmonic nanoantenna sensor array with infrared radiation, and (iii) detecting reflected and/or transmitted radiation from the plasmonic nanoantenna sensor array over a wavelength range of 2 pm to 20 pm.
  • the method may further include identifying a molecular vibration from the reflected and/or transmitted radiation.
  • the plasmonic nanoantenna sensor array may have a resonance bandwidth of at least 1.5 pm in the midinfrared region.
  • the method may also include producing a barcode format output based on the detected radiation.
  • a plasmonic nanoantenna sensor array for sensing a molecular vibration.
  • the plasmonic nanoantenna sensor array includes an infrared light-permeable substrate having a surface, and an array of plasmonic nanoantennas arranged on the surface.
  • Each plasmonic nanoantenna has a main arm having a first finite length defined by a first main arm end portion and a second main arm end portion, a secondary arm having a second finite length defined by a first secondary arm end portion and a second secondary arm end portion, and an intermediate arm arranged to be connected to the second main arm end portion and the second secondary arm end portion.
  • the first main arm end portion and the first secondary arm end portion are arranged to extend in a same direction, and the first finite length being longer than the second finite length.
  • the first finite length and the second finite length may vary among the plasmonic nanoantennas.
  • a plasmonic nanoantenna comprising: a first arm; and a second arm that is shorter than and arranged parallel to and spaced from the first arm; wherein a first end of the second arm is arranged intermediate opposed first and second ends of the first arm.
  • Figure 1A is a front view of a plasmonic nanoantenna according to a first embodiment.
  • Figure 1 B is an atomic force microscopy image of the plasmonic nanoantenna of Figure 1A.
  • Figure 2A is a microfluidic system for molecular identification using the plasmonic nanoantenna of Figure 1A.
  • Figure 2B is a perspective view of the plasmonic nanoantenna in the microfluidic system of Figure 2A transmitting and reflecting light as a result of plasmon-phonon coupling.
  • Figure 6B shows a transmission intensity of the plasmonic nanoantenna of Figure 2A for different folding degrees (AL) across different wavelengths.
  • Figure 6C shows a reflection intensity of the plasmonic nanoantenna of Figure 2A for different folding degrees (AL) across different wavelengths.
  • Figure 6D shows the sensitivity of the plasmonic nanoantenna of Figure 2A in transmission mode (AT) for different folding degrees (AL) across different wavelengths.
  • Figure 10D to 10G are enlarged views of four of the hyperspectral images of Figure 10C at four respective wavelengths of 4.67pm, 5.66pm, 6.88pm, and 7.46pm for the bare analyte.
  • Figure 11 H is a reconstructed fingerprint barcode image of the plasmonic nanoantenna sensor array of Figure 10A for the acetone analyte state.
  • Figure 13A is a schematic diagram of a third plasmonic nanoantenna sensor array according to an alternative embodiment to the second plasmonic nanoantenna sensor array of Figure 8F.
  • Figure 14B is the broadband responses for the third plasmonic nanoantennas of Figure 13A at positions A1 , A8 and A16, with coating of silk protein and PMMA.
  • Figure 16B is a reflection change spectrum of the third plasmonic nanoantenna sensor array of Figure 13A showing the fingerprint absorption peaks of the six different analytes of Figure 16A.
  • the first main arm end portion 1110, and the first secondary arm end portion 1210 extends in a same direction.
  • the first finite length, L1 is longer than the second finite length, L2.
  • the second finite length, L2 is 400 nm.
  • the plasmonic nanoantenna 1000 further includes an intermediate arm 1300 having a third finite length, L3.
  • the third finite length, L3 is 400 nm.
  • the main arm 1100, the secondary arm 1200, and the intermediate arm 1300 have respective widths, w of 200 nm, and respective heights (not shown in Figure 1 ) of 10 nm.
  • the intermediate arm 1300 is perpendicularly connected to the second main arm end portion 1120 and the second secondary main arm end portion 1220 to form a hook shape.
  • the plasmonic nanoantenna 1000 is also referred to as a hook nanoantenna 1000.
  • the main arm 1100, the secondary arm 1200, and the intermediate arm 1300 cooperate to form a generally C-shape or partial-square hook and are formed as a unitary component, and disposed on an infrared, light-permeable substrate 1400.
  • the substrate 1400 is made of CaF2.
  • the first arm 1100, the second arm 1200, and the intermediate arm 1300 are made of gold.
  • a clean CaF2 wafer is first coated with a 220 nm thick layer of poly(methyl methacrylate) (PMMA) ebeam lithography resist, followed by a thin conducting polymer film to form an intermediate product.
  • PMMA poly(methyl methacrylate)
  • the polymer film used is “ESpacer (Showa Denko Singapore)”.
  • the spin coating rates for PMMA and ESpacer are 4000 rpm and 2000 rpm for 1 minute.
  • the backing process at 180°C for 2 minutes is conducted after spin-coating to evaporate the remaining water molecules.
  • the first finite length, L1 , the second finite length, L2, and the third finite length, L3, are not limited to the values listed in the described embodiment.
  • the first finite length, L1 may be selected from a range between 400 nm to 2500 nm.
  • the second finite length, L2 may be selected from a range between 200 nm to 1100 nm.
  • the third finite length, L3 may be selected from a range between 200 nm to 800 nm.
  • the respective widths of the main arm, the secondary arm, and the intermediate arm may be selected from a range between 100 nm to 400 nm.
  • the respective heights of the main arm, the secondary arm, and the intermediate arm may be selected from a range between 10 nm to 150 nm.
  • FIG. 2A illustrates a microfluidic system 1500 for molecular identification using the plasmonic nanoantenna 1000.
  • the microfluidic system 1500 includes a microfluidic channel 1510 defined by the CaF2 substrate 1400, and a substrate 1520 made of polydimethylsiloxane (PDMS).
  • a first end 1512 of the microfluidic channel 1510 is attached to a liquid inlet 1530 for supplying an aqueous solution of molecules 102 to be identified.
  • a second end 1514 of the microfluidic channel 1510 is attached to a liquid outlet 1540 for draining the aqueous solution from the microfluidic channel 1510.
  • PDMS polydimethylsiloxane
  • the infrared radiation 100 is linearly polarized, and arranged to be perpendicularly incident on the plasmonic nanoantenna 1000 such that an electrical field of the infrared radiation 100 is substantially parallel to the main arm 1100 and the secondary arm 1200 (or in the same direction as the first main arm end portion 1110 and the first secondary arm end portion 1210).
  • the infrared radiation 100 excites a plasmonic resonance of the plasmonic nanoantenna 1000.
  • P and M represent the amplitude of resonance of the plasmonic nanoantenna 1000 and the molecular vibrations, respectively;
  • 0 a ndd represent the angular frequency of resonance for the plasmonic nanoantenna 1000 and molecular vibration, respectively;
  • EIT electromagnetic induced transparent
  • the substantial enhancement of the sensing signal is observed in the change of transmission or reflection intensity compared with intrinsic molecule absorption.
  • Equations (10), (11 ), and (12) are used to extract absorptive loss, y a and radiative loss, y r of the plasmonic nanoantenna 1000 by fitting the resonance spectrum in the frequency domain from simulation, as illustrated in Figure 4 which comprises Figures 4A to 4F.
  • the radiative loss, y r - of the plasmonic nanoantenna 1000 is tuned by adjusting the plasmonic nanoantenna's radiation capability by inducing inverse current in the secondary arm 1200 of the plasmonic nanoantenna 1000. This can be done by adjusting the second finite length, L2 relative to the first finite length, L1 .
  • the difference in length between the first finite length, L1 and the second finite length, L2 is referred to as a folding degree (AL) of the plasmonic nanoantenna 1000.
  • the radiative loss, y r and the absorptive loss, y a of the plasmonic nanoantenna 1000 is tuned continuously.
  • the angular frequency of resonance for the plasmonic nanoantenna, ⁇ 0 remains unchanged.
  • the coupling efficiency, ⁇ is assumed to be much smaller compared with the radiative loss, y r and absorptive loss, y a of the plasmonic nanoantenna 1000, and the absorptive loss, y m of the molecules 102.
  • Equation (13) is simplified to: where: fdenotes a ratio (y r /y a ) between radiative loss (y r ) and absorptive loss (y a ) of the plasmonic nanoantenna 1000.
  • ⁇ T represents the intensity change (or sensitivity) of the plasmonic nanoantenna 1000 in transmission mode.
  • ⁇ R which represents the intensity change (or sensitivity) of the plasmonic nanoantenna 1000 in reflection mode, and is defined by equation (15):
  • Figure 5 comprising Figures 5A to 5C, illustrates three infrared response spectrums for the transmitted light 110, the reflected light 120, and absorbed light respectively, for different folding degrees (AL) of the plasmonic nanoantenna 1000.
  • A folding degree
  • FIG. 6A illustrates two line graphs 510,512 for the radiative loss (y r ) and absorptive loss (y a ) of the plasmonic nanoantenna 1000 at different folding degrees (AL).
  • sensitivity in transmission mode (AT) of the plasmonic nanoantenna 1000 can be calculated by normalized transmittance (AT/T).
  • Figure 6D illustrates the sensitivity of the plasmonic nanoantenna 1000 in transmission mode (AT) for different folding degrees (AL) across different wavelengths.
  • Figure 6E illustrates the sensitivity of the plasmonic nanoantenna 1000 in reflection mode (AR) for different folding degrees (AL) across different wavelengths.
  • Figure 6F illustrates two point graphs 514,516 for a normalized sensitivity of the plasmonic nanoantenna 1000 in transmission mode (AT) and in reflectance mode (AR) respectively for different folding degrees (AL).
  • the resonance wavelength of the plasmonic nanoantenna 1000 increases with increasing antenna length, L.
  • a difference in length between the first finite length, L1 and third finite length, L3 affects the nearfield electric and magnetic field due to a decrease in the electrical length of dipole charge.
  • Figure 7B illustrates the sensitivity of the plasmonic nanoantenna 1000 in reflection mode (AR) for different antenna lengths (L) across different wavelengths.
  • a transition of line shape from Fano-like to E IT-like occurs when the resonance wavelength of the plasmonic nanoantenna 1000 matches with the molecular absorption wavelength of the molecule to be identified.
  • Figure 7C illustrates a point graph for the normalized sensitivity of the plasmonic nanoantenna 1000 in in reflectance mode (AR) for different antenna lengths (L). From Figure 7C, it can be seen that the highest sensitivity for the plasmonic nanoantenna 1000 is achieved when the resonance wavelength of the plasmonic nanoantenna 1000 is well-matched to the molecular vibrations of the molecule to be identified.
  • the first finite length, L1 is three times that of the second finite length, L2 to achieve the highest sensitivity for the plasmonic nanoantenna 1000 operating in reflectance mode (AR).
  • Figure 8A illustrates a first plasmonic nanoantenna sensor array 2000 for sensing molecular vibrations in the mid-infrared region.
  • the first plasmonic nanoantenna sensor array 2000 includes an infrared transparent substrate 2010 having a surface 2012.
  • the first plasmonic nanoantenna sensor array 2000 further includes sixteen pixels 2100 arranged on the surface 2012 in a 4x4 configuration.
  • Figure 8B illustrates a first pixel 2100a of the first plasmonic nanoantenna sensor array 2000.
  • the first pixel 2100a includes sixteen first plasmonic nanoantennas 1000a arranged in a 4x4 configuration.
  • Each of the first plasmonic nanoantennas 1000a includes respective main arms 1100a having respective first finite lengths, L1 that are of the same first length of 1200nm.
  • each of the first plasmonic nanoantennas 1000a include respective secondary arms 1200a having respective second finite lengths, L2 that are of the same second length of 400nm.
  • each of the first plasmonic nanoantennas 1000a include respective intermediate arms 1300a having respective third finite lengths, L3 that are of the same third length of 400nm.
  • Figure 8C illustrates a second pixel 2100b of the first plasmonic nanoantenna sensor array 2000
  • the second pixel 2100b includes sixteen second plasmonic nanoantennas 1000b.
  • Each of the second plasmonic nanoantennas 1000b includes respective main arms 1100b having respective first finite lengths, L1 that are of the same fourth length of 2100nm.
  • each of the second plasmonic nanoantennas 1000b include respective secondary arms 1200b having respective second finite lengths, L2 that are of the same fifth length of 700nm.
  • each of the second plasmonic nanoantennas 1000b include respective intermediate arms 1300b having respective third finite lengths, L3 that are of the same sixth length of 400nm.
  • the first length differs from the fourth length
  • the second length differs from the fifth length
  • the third length differs from the sixth length.
  • the first plasmonic nanoantennas 1000a and the second plasmonic nanoantennas 1000b have different dimensions.
  • Figure 8D shows a far-field response of the first plasmonic nanoantenna 1000a in reflectance mode.
  • the first plasmonic nanoantenna 1000a has a resonant wavelength of 4.5 pm.
  • Figure 8E shows a far-field response of the second plasmonic nanoantenna 1000b in reflectance mode.
  • the plasmonic nanoantenna 1000b has a resonant wavelength of 6.2 pm.
  • Figure 9A shows a far-field response of each pixel 2100 of the first plasmonic nanoantenna sensor array 2000 in reflectance mode.
  • Figure 9B shows a far-field response of the first plasmonic nanoantenna sensor array 2000 in reflectance mode.
  • the far-field response of the first plasmonic nanoantenna sensor array 2000 follows an envelop of the far-field response created by each pixel 2100 of the first plasmonic nanoantenna sensor array 2000.
  • Hyperspectral imaging is applied to the first plasmonic nanoantenna sensor array 2000 to retrieve an enhanced fingerprint absorption with one-time data acquisition.
  • Figure 10A is a schematic diagram of the first plasmonic nanoantenna sensor array 2000 having the sixteen pixels 2100 (first pixel, P1 to sixteenth pixel, P16) for hyperspectral imaging.
  • Figure 10B shows the hyperspectral response of the sixteen pixels 2100 of the first plasmonic nanoantenna array 2000.
  • the first plasmonic nanoantenna sensor array 2000 is used to capture the hyperspectral image from a wavelength of 4 pm (2500 cm -1 ) to 9 pm (1111 cm -1 ) by FPA under four analyte states: bare, acetone, IPA and a 1 :1 mixture of IPA and acetone.
  • Figure 10C illustrates the hyperspectral images captured by the first plasmonic nanoantenna sensor array 2000 at different wavelengths for the four analyte states.
  • the fingerprint absorption of acetone and IPA is reflected on the hyperspectral image of HNA array at absorption wavelengths. For the 1 :1 mixture of IPA and acetone, the combination of image change is observed at all absorption wavelengths.
  • Figure 10D to Figure 10G illustrate enlarged views of four of the hyperspectral images 2110,2120,2130,2140 captured by the first plasmonic nanoantenna sensor array 2000 at four respective wavelengths of 4.67 pm, 5.66 pm, 6.88 pm, and 7.46 pm for the bare analyte state.
  • the pixels 2100 that have peak resonant wavelengths around 4.67 pm, 5.66 pm, 6.88 pm, and 7.46 pm are the first pixel, P1 , the sixth pixel, P6, the twelfth pixel, P12, and the sixteenth pixel, P16.
  • a first area 2112 of the hyperspectral image 2110 matching a location of the first pixel, P1 in Figure 10A is illuminated.
  • a second area 2122 of the hyperspectral image 2120 matching a location of the sixth pixel, P6 in Figure 10A is illuminated.
  • a third area 2132 of the hyperspectral image 2130 matching a location of the twelfth pixel, P12 in Figure 10A is illuminated.
  • a fourth area 2142 of the hyperspectral image 2140 matching a location of the sixteenth pixel, P16 in Figure 10A is illuminated.
  • the normalized spectral response of each pixel 2100 of the first plasmonic nanoantenna sensor array 2000 in reflectance mode is extracted and a difference of the reflected signal induced by molecular absorption is calculated.
  • Figure 11A illustrates an extracted normalized reflection spectrum of each pixel 2100 of the first plasmonic nanoantenna sensor array 2000 for the IPA analyte state.
  • Figure 11 B illustrates an extracted normalized reflection spectrum of each pixel 2100 of the first plasmonic nanoantenna sensor array 2000 for the acetone analyte state.
  • Figure 11 C illustrates an extracted normalized reflection spectrum of each pixel 2100 of the first plasmonic nanoantenna sensor array 2000 for the 1 :1 acetone-IPA analyte state.
  • Figure 11 G illustrates a reconstructed fingerprint barcode image of the plasmonic nanoantenna sensor array 2000 for the IPA analyte state.
  • Figure 11 H illustrates a reconstructed fingerprint barcode image of the plasmonic nanoantenna sensor array 2000 for the acetone analyte state.
  • Figure 111 illustrates a reconstructed fingerprint barcode image of the plasmonic nanoantenna sensor array 2000 for the 1 :1 acetone-IPA analyte state.
  • the absorption peaks of IPA at 7.0 pm to 8.0 pm are captured by the ninth pixel, P9 to the thirteenth pixel, P13 (refer to Figure 10A), while the absorption peak of IPA at 8.5 pm is captured by the sixteenth pixel, P16.
  • the absorption peaks of acetone at 5.74 pm is captured by the first pixel, P1 to the third pixel, P3.
  • the absorption peak of acetone at 7.0 pm to 7.5 pm is captured by the ninth pixel, P9 to the eleventh pixel, P11 .
  • the absorption peak of acetone at 8.0 pm is captured by the fourteenth pixel, P14.
  • the absorptive peaks of both IPA and acetone are captured resulting in a combination of the fingerprint barcode image of Figure 11 G and 11 H.
  • the first plasmonic nanoantenna sensor array 2000 is able to capture and produce fingerprint barcode images that have a small footprint and are spatially tunable so that the entire spectra of an analyte can be captured in one testing. This dramatically reduces the time for broadband fingerprint retrieval, allowing for ultrasensitive and ultrafast molecular screening in ultra-broadband wavelength range with ultra-small volume.
  • each pixel 2100 of the first plasmonic nanoantenna sensor array 2000 may have more than sixteen plasmonic nanoantennas 1000.
  • each pixel 2100 may include twenty five plasmonic nanoantennas 1000 arranged in a 5x5 configuration.
  • the first plasmonic nanoantenna sensor array 2000 may include more than sixteen pixels 2100.
  • the first plasmonic nanoantenna sensor array 2000 may include twenty five pixels 2100 arranged in a 5x5 configuration.
  • Figure 8F illustrates a second plasmonic nanoantenna sensor array 3000 for sensing molecular vibrations in the mid-infrared region. Similar to the first plasmonic nanoantenna sensor array 2000, the second plasmonic nanoantenna sensor array 3000 includes an infrared transparent substrate 3010 having a surface 3012. The second plasmonic nanoantenna sensor array 3000 further includes sixteen third pixels 3100a arranged on the surface 3012 in a 4x4 configuration.
  • Figure 8G illustrates the third pixel 3100a of the second plasmonic nanoantenna sensor array 3000. The third pixel 3100a includes sixteen third plasmonic nanoantennas 1000c arranged in a 4x4 configuration.
  • Each of the third plasmonic nanoantennas 1000c includes respective main arms 1100c, secondary arms 1200c, and intermediate arms 1300c.
  • the first finite lengths, L1 of respective main arms 1100c gradually increases in length from a bottom left corner to a top right corner of the 4x4 configuration.
  • the second finite lengths, L2 of respective secondary arms 1200c also gradually increase in length from a bottom left corner to a top right corner of the 4x4 configuration.
  • the third finite lengths, L3 of respective intermediate arms 1300c also gradually increase in length from a bottom left corner to a top right corner of the 4x4 configuration.
  • the antenna length, L of respective third plasmonic nanoantennas 1000c increases from the bottom left corner to the top right corner of the 4x4 configuration.
  • the smallest third plasmonic nanoantenna 1000c (bottom left corner of 4x4 configuration) has the same dimension and far-field response (refer to Figure 8D) as the first plasmonic nanoantenna 1000a, while the largest third plasmonic nanoantenna 1000c (top right corner of 4x4 configuration) has the same dimensions and far-field response (refer to Figure 8E) as the second plasmonic nanoantenna 1000b.
  • Figure 12A illustrates a far-field response of the second plasmonic nanoantenna sensor array 3000 in reflectance mode. Like the first plasmonic nanoantenna sensor array 2000, the second plasmonic nanoantenna sensor array 3000 has a resonance bandwidth of 1 .5 pm.
  • the first plasmonic nanoantenna sensor array 2000 and the second plasmonic nanoantenna sensor array 3000 are able to monitor molecular behaviour dynamically due to their fast response time.
  • the first plasmonic nanoantenna sensor array 2000 and the second plasmonic nanoantenna sensor array 3000 are independently integrated in the microfluidic system 1500 of Figure 2A for molecular detection in an 1 aqueous environment.
  • a liquid analyte is injected into the microfluidic system 1500, the first plasmonic nanoantenna sensor array 2000 and the second plasmonic nanoantenna sensor array 3000 are exposed to the liquid analyte.
  • the infrared radiation 100 Upon exposure to the infrared radiation 100, plasmon-phonon coupling occurs, and the reflected light 120 is collected and analysed. To compare sensing performance, the infrared radiation 100 is shone on the CaF2 substrate 1400 without the first plasmonic nanoantenna sensor array 2000 or the second plasmonic nanoantenna sensor array 3000 to get intrinsic infrared absorption caused by water.
  • Figure 12B illustrates the broadband response of water resulting from the intrinsic infrared absorption. A small change of 0.4% in the reflectance of water is observed.
  • Figure 12C illustrates three line graphs 1230,1240, 1250 for the broadband response of: (i) the first plasmonic nanoantenna sensor array 2000, (ii) the first plasmonic nanoantenna sensor array 2000 in water, and (iii) water respectively.
  • Figure 12D illustrates three line graphs 1260,1270, 1280 for the broadband response of: (i) the second plasmonic nanoantenna sensor array 3000, (ii) the second plasmonic nanoantenna sensor array 3000 in water, and (iii) water, respectively.
  • An absorption peak i.e.
  • EIT-like resonance lineshape, near 6 pm is observed for line graph 1240 and line graph 1270 which indicates that sensitivity is enhanced in the first plasmonic nanoantenna sensor array 2000 and the second plasmonic nanoantenna sensor array 3000.
  • the sensitivity of the first plasmonic nanoantenna sensor array 2000 and the second plasmonic nanoantenna sensor array 3000 is calculated as 0.67 and 0.72, respectively, which is close to the sensitivity of 0.73 achieved by the plasmonic nanoantenna 1000.
  • the first plasmonic nanoantenna sensor array 2000 and the second plasmonic nanoantenna sensor array 3000 achieves dynamic broadband monitoring of multiple infrared molecular absorption.
  • FIG. 12E illustrates a dynamic broadband response of the second plasmonic nanoantenna sensor array 3000 as acetone is slowly injected into the water over time.
  • Figure 12F illustrates an integrated absorbance of each fingerprint absorption by the second plasmonic nanoantenna sensor array 3000 as acetone is slowly injected into water over time.
  • the absorption peak of water at 6.0 pm decreases while the absorption peaks of acetone at 5.81 pm, 7.0 pm, and 7.3 pm increase.
  • the diffusion process becomes saturated 50 seconds after acetone injection.
  • a third plasmonic nanoantenna sensor array 4000 is disclosed, and reference to the third plasmonic nanoantenna sensor array 4000 refers to the specific embodiment of the second plasmonic nanoantenna sensor array 3000 having the single third pixel.
  • Figure 13A illustrates the third plasmonic nanoantenna sensor array 4000 having sixteen third plasmonic nanoantennas 1000c as described in the previous embodiment i.e., having incremental antenna lengths, L from position A1 to position A16.
  • a performance of the third plasmonic nanoantenna sensor array 4000 is described next.
  • a redshift of the third plasmonic nanoantenna sensor array 4000 is caused by an effect induced by the refractive index of the analytes indicating the refractometry function of the third plasmonic nanoantenna sensor array 4000.
  • the third plasmonic nanoantenna sensor array 4000 has a better enhancement effect of multiple absorption peaks with broad wavelength ranges compared to the third plasmonic nanoantennas 1000c at positions A1 , A8 and A16 which only reaches peak enhancement at narrow wavelength ranges near the resonance wavelengths.
  • both the third plasmonic nanoantenna sensor array 4000 and the third plasmonic nanoantennas 1000c at positions A1 , A8, and A16 show significant enhancements (in 3 orders of magnitude) of absorption spectrum with respect to the direct measurements of the silk protein and the PMMA.
  • the third plasmonic nanoantenna sensor array 4000 is integrated in the microfluidic system 1500 of Figure 2A for molecular detection in an aqueous environment.
  • Figure 15A illustrates three line graphs 1510,1520,1530 for the broadband response of: (i) the third plasmonic nanoantenna sensor array 4000, (ii) the third plasmonic nanoantenna sensor array 4000 in water, and (iii) water, respectively. From line graph 1520, an enhancement of the O-H bond of water at 6.0 pm is observed.
  • FIG. 15B illustrates a dynamic broadband response of the third plasmonic nanoantenna sensor array 4000 as acetone is slowly injected into the water over time. Multiple fingerprint absorption peaks are captured to obtain a rich information of chemical bond changes, reflecting in-situ concentration information of acetone and water changing dynamically over time.
  • Figure 15D illustrate an integrated absorbance of each fingerprint absorption by the third plasmonic nanoantenna sensor array 4000 as acetone is slowly injected into water over time.
  • the recognition capabilities of the third plasmonic nanoantenna sensor array 4000 is compared to that of the plasmonic nanoantenna 1000 using six different analytes: (i) ethanol, (ii) methanol, (iii) a mixture of ethanol and methanol, (iv) IPA, (v) a mixture of IPA and methanol, and (vi) a mixture of IPA and ethanol.
  • Each analyte is injected into the microfluidic system 1500, and the resulting broadband response of the plasmonic nanoantenna 1000 and the third plasmonic nanoantenna sensor array 4000 is captured.
  • Figure 16A illustrates the broadband response of the plasmonic nanoantenna 1000 and the third plasmonic nanoantenna sensor array 4000 for the six different analytes: (i) 1 % ethanol, (ii) 1 % methanol, (iii) a mixture of 1 % ethanol and 1 % methanol, (iv) 1 % IPA, (v) a mixture of 1 % IPA and 1 % methanol, and (vi) a mixture of 1 % IPA and 1 % ethanol.
  • the plasmonic nanoantenna 1000 has a narrow bandwidth response near the resonance wavelength of 6.5 pm.
  • the third plasmonic nanoantenna sensor array 4000 has a wide bandwidth response from 6 pm to 9 pm.
  • the dip at 6.0 pm represents the 0-H bond of water, which is the common solvent in both the plasmonic nanoantenna 1000 and the third plasmonic nanoantenna sensor array 4000.
  • Figure 16B illustrates a reflection change spectrum of the third plasmonic nanoantenna sensor array 4000 showing the fingerprint absorption peaks of the six different analytes: (i) 1 % ethanol, (ii) 1 % methanol, (iii) a mixture of 1 % ethanol and 1 % methanol, (iv) 1 % IPA, (v) a mixture of 1 % IPA and 1 % methanol, and (vi) a mixture of 1 % IPA and 1 % ethanol. Since the concentration of the six analytes are low, the change of reflection at absorption is small. To process the small signal, a second derivative is applied to extract characteristics of each spectrum from the third plasmonic nanoantenna sensor array 4000.
  • Figure 16C illustrates a second derivative of the reflection change spectrum of the third plasmonic nanoantenna sensor array 4000 for the six different analytes.
  • PCA principal component analysis
  • PCA is further applied to process the small signal for extracting multi-dimensional information including absorption peaks induced by vibration of chemical bonds, wavelength shift of resonance induced by refractive index of molecules, and intensity change of water absorption induced by loading effect of wavelength detuning.
  • PCA is performed in MATLAB_R2020a.
  • a covariance matrix is computed using a factorization of singular value decomposition (SVD) for the normalized set of features from which the eigenvectors and eigenvalues are extracted.
  • SVD singular value decomposition
  • Each principal component is constructed as a linear combination of the initial features. The first three principal components are then used to display 3D scatter plots of the features.
  • Figure 16D illustrates the PCA-processed spectra of the plasmonic nanoantenna 1000 and the third plasmonic nanoantenna sensor array 4000 after dimension reduction to three principal components, PC1 , PC2 and PC3.
  • the 1 st principal component (PC1 ) represents the modulation effect of water absorption peaks by loading effect of wavelength shift at 6.0 pm.
  • the 2nd principal component (PC2) represents the wavelength shift of resonance induced by the refractive index of the analyte.
  • the 1 st principal component (PC1 ) and the 2nd principal component (PC2) are flipped in terms data feature from the spectrum for the third plasmonic nanoantenna sensor array 4000 indicating the different responses for refractometry function and spectroscopy function.
  • the 3rd principal component (PC3) represents the fingerprint absorption of molecules in the plasmonic nanoantenna 1000 and the third plasmonic nanoantenna sensor array 4000.
  • Figure 16E illustrates a 3D principal component space for the spectrum data of the six different analytes collected from the plasmonic nanoantenna 1000.
  • Figure 16F illustrates a 3D principal component space for the spectrum data of the six different analytes collected from the third plasmonic nanoantenna sensor array 4000.
  • the order of principal component represents a degree of difference between each spectrum.
  • each point represents the spectrum data from the plasmonic nanoantenna 1000 or the third plasmonic nanoantenna sensor array 4000, and each cluster represents one type of molecule combination.
  • the various embodiments described herein should not be construed as being limitative.
  • the plasmonic nanoantenna 1000, as well as the first plasmonic nanoantenna 1000a, second plasmonic nanoantenna 1000b, and the third plasmonic nanoantenna 1000c may not be made of gold.
  • Other materials such as aluminium, molybdenum, graphene, or a composite made of a silicon nitride layer sandwiched between silver and gold, or other materials that are suitable for the specific application are understood to be within the scope of the disclosure.
  • the infrared light-permeable substrate 1400 may not be made from CaF2.
  • suitable materials include, but are not limited to, BaF2, MgF2, ZnS, ZnSe, sapphire and quartz.
  • applications of the first plasmonic nanoantenna sensor array 2000, the second plasmonic nanoantenna sensor array 3000, the third plasmonic nanoantenna sensor array 4000 are not limited to molecular identification in an aqueous environment, but may also be applied to gas sensing of CO2, NOx, and SOx, which is useful for environmental monitoring of air pollution as well as volatile organic compound (VOC) like acetone, ethanol, and isoprene for healthcare monitoring and disease diagnosis.
  • VOC volatile organic compound

Landscapes

  • Physics & Mathematics (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • General Physics & Mathematics (AREA)
  • Chemical & Material Sciences (AREA)
  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Optics & Photonics (AREA)
  • Analytical Chemistry (AREA)
  • Biochemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • Immunology (AREA)
  • Pathology (AREA)
  • Investigating Or Analysing Materials By Optical Means (AREA)

Abstract

L'invention concerne une nanoantenne plasmonique (1000). Dans un mode de réalisation spécifique, la nanoantenne plasmonique (1000) comprend un bras principal (1100) ayant une première longueur limitée définie par une première partie d'extrémité de bras principal (1110) et une seconde partie d'extrémité de bras principal (1120), un bras secondaire (1200) ayant une seconde longueur limitée définie par une première partie d'extrémité de bras secondaire (1210) et une seconde partie d'extrémité de bras secondaire (1220), et un bras intermédiaire (1300) agencé pour être connecté à la seconde partie d'extrémité de bras principal (1120) et à la seconde partie d'extrémité de bras secondaire (1220). Dans ce mode de réalisation, la première partie d'extrémité de bras principal (1110) et la première partie d'extrémité de bras secondaire (1210) sont agencées pour s'étendre dans une même direction, et la première longueur limitée est plus longue que la seconde longueur limitée. L'invention concerne également des réseaux de capteurs à nanoantenne plasmonique (2000, 3000, 4000) qui comprennent la nanoantenne plasmonique (1000) pour détecter une vibration moléculaire. L'invention concerne en outre une méthode de détection d'une molécule.
PCT/SG2021/050487 2020-08-24 2021-08-19 Nanoantenne plasmonique, réseaux de capteurs à nanoantenne plasmonique, et méthode associée WO2022045970A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
SG10202008096X 2020-08-24
SG10202008096X 2020-08-24

Publications (1)

Publication Number Publication Date
WO2022045970A1 true WO2022045970A1 (fr) 2022-03-03

Family

ID=80352948

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/SG2021/050487 WO2022045970A1 (fr) 2020-08-24 2021-08-19 Nanoantenne plasmonique, réseaux de capteurs à nanoantenne plasmonique, et méthode associée

Country Status (1)

Country Link
WO (1) WO2022045970A1 (fr)

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20130162375A1 (en) * 2011-12-26 2013-06-27 Asahi Glass Company, Limited Method for producing metamaterial and metamaterial
CN109799625A (zh) * 2019-01-18 2019-05-24 西安电子科技大学 基于钙钛矿的超材料太赫兹调制器件及制备方法
WO2019206430A1 (fr) * 2018-04-27 2019-10-31 Ecole Polytechnique Federale De Lausanne (Epfl) Procédé et appareil de spectrométrie pour examiner une absorption infrarouge d'un échantillon

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20130162375A1 (en) * 2011-12-26 2013-06-27 Asahi Glass Company, Limited Method for producing metamaterial and metamaterial
WO2019206430A1 (fr) * 2018-04-27 2019-10-31 Ecole Polytechnique Federale De Lausanne (Epfl) Procédé et appareil de spectrométrie pour examiner une absorption infrarouge d'un échantillon
CN109799625A (zh) * 2019-01-18 2019-05-24 西安电子科技大学 基于钙钛矿的超材料太赫兹调制器件及制备方法

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
CHANG YUN-TZU, LAI YUEH-CHUN, LI CHUNG-TIEN, CHEN CHENG-KUANG, YEN TA-JEN: "A multi-functional plasmonic biosensor", OPTICS EXPRESS, vol. 18, no. 9, 26 April 2010 (2010-04-26), pages 9561, XP055911208, DOI: 10.1364/OE.18.009561 *
REN ZHIHAO, CHANG YUHUA, MA YIMING, SHIH KAILING, DONG BOWEI, LEE CHENGKUO: "Leveraging of MEMS Technologies for Optical Metamaterials Applications", ADVANCED OPTICAL MATERIALS, WILEY, DE, vol. 8, no. 3, 1 February 2020 (2020-02-01), DE , pages 1900653, XP055911211, ISSN: 2195-1071, DOI: 10.1002/adom.201900653 *
REN ZHIHAO; WEI JINGXUAN; HASAN DIHAN; DONG BOWEI; ZHOU GUANGYA; LEE CHENGKUO: "Nanoplasmonics Enhanced Broadband Ultra-Sensitive Mid-Ir Sensor Array Integrated with Microfluidics", 2019 20TH INTERNATIONAL CONFERENCE ON SOLID-STATE SENSORS, ACTUATORS AND MICROSYSTEMS & EUROSENSORS XXXIII (TRANSDUCERS & EUROSENSORS XXXIII), IEEE, 23 June 2019 (2019-06-23), pages 645 - 648, XP033600128, DOI: 10.1109/TRANSDUCERS.2019.8808524 *

Similar Documents

Publication Publication Date Title
Adato et al. Engineering mid-infrared nanoantennas for surface enhanced infrared absorption spectroscopy
Patel et al. Encoding and tuning of THz metasurface-based refractive index sensor with behavior prediction using XGBoost Regressor
Wen et al. Multiband and ultrahigh figure-of-merit nanoplasmonic sensing with direct electrical readout in Au-Si nanojunctions
Potyrailo et al. Optical waveguide sensors in analytical chemistry: today’s instrumentation, applications and trends for future development
Niggemann et al. Remote sensing of tetrachloroethene with a micro-fibre optical gas sensor based on surface plasmon resonance spectroscopy
US20180003706A1 (en) System, method, and module for biomarker detection
WO2009031838A1 (fr) Analyseur spectral pour mesurer l'épaisseur de couches minces organiques et en identifier les constituants chimiques à l'aide de la microscopie cars
EP3907490B1 (fr) Détection d'un échantillon chimique en utilisant une microcavité optique
Gu et al. Waveguide-enhanced surface plasmons for ultrasensitive SERS detection
CN103649718A (zh) 生成超材料的方法及由此生成的超材料
Shakoor et al. Plasmonic sensor monolithically integrated with a CMOS photodiode
Kazemi‐Zanjani et al. Multiwavelength Surface‐Enhanced Raman Spectroscopy Using Rainbow Trapping in Width‐Graded Plasmonic Gratings
CN108732138A (zh) 一种光子超颖表面生物传感器
Chen et al. Enhanced vibrational spectroscopy, intracellular refractive indexing for label-free biosensing and bioimaging by multiband plasmonic-antenna array
Tu et al. A novel micromachined Fabry-Perot interferometer integrating nano-holes and dielectrophoresis for enhanced biochemical sensing
Hong et al. Integration of Faradaic electrochemical impedance spectroscopy into a scalable surface plasmon biosensor for in tandem detection
Lee et al. Frontiers in terahertz imaging applications beyond absorption cross-section and diffraction limits
Levi et al. Sensitivity analysis of a photonic crystal structure for index-of-refraction sensing
Malek et al. High performance biosensor composed of 1D defective photonic crystal for sensing and detection of distinguished blood components
US6661520B1 (en) Sensor system of surface plasmon resonance (SPR) and measuring method thereof
US8164755B2 (en) Method for determining an analyte in a sample
Tai et al. Escherichia coli fiber sensors using concentrated dielectrophoretic force with optical defocusing method
WO2022045970A1 (fr) Nanoantenne plasmonique, réseaux de capteurs à nanoantenne plasmonique, et méthode associée
Saad et al. Theoretical evaluation of a fiber-optic SPR biosensor based on a gold layer treated with thiol acid
Visser et al. Refractive index sensing in the visible/NIR spectrum using silicon nanopillar arrays

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 21862209

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 21862209

Country of ref document: EP

Kind code of ref document: A1