A device for realizing non-reciprocal optical fluidic control and its application
The asymmetric heat transfer path is constructed through the stacking of multi-layer asymmetric plasmon nanodisks, which solves the problem that existing optical flow control devices cannot achieve non-reciprocal liquid manipulation, and simplified non-reciprocal fluid control, expands applications in the fields of biosensing and drug detection.
Patent Information
- Application Number
- CN202310542856.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2023-05-11
- Publication Date
- 2025-08-12
- Estimated Expiration
- 2043-05-11
AI Technical Summary
Existing optical flow control devices cannot achieve non-reciprocal liquid manipulation, which limits its application expansion in the fields of biosensing, drug detection, etc.
By constructing a stack of multi-layer asymmetric plasmon nanodiscs, a heterodimer structure is formed, and photoexcitation and heat transfer are carried out along different paths under forward and backward irradiation, resulting in opposite temperature gradients, thereby achieving non-reciprocal fluid control.
The construction process of non-reciprocal devices is simplified, external magnetic fields or material modulation is avoided, non-reciprocal fluid control is realized, and application potential in fields such as biosensing and drug detection is expanded.
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Figure CN116553473B_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of optofluidics, and in particular to a device for implementing non-reciprocal optofluidics and applications thereof. Background Art
[0002] Optofluidics refers to the manipulation of light and fluids at the micro- and nanoscale, studying unique phenomena in these two areas through their interactions. Currently, optofluidics research has two main branches: one is the manipulation of light through fluids, such as research on droplet lenses; the other is the manipulation of fluids or micro- and nanoparticles through light, such as research on optical tweezers and optical trapping. In recent years, optofluidic devices and systems based on the light-based manipulation of fluids have been widely applied in research fields such as biosensing, drug detection, drug identification, and chemical analysis.
[0003] However, existing optofluidic devices are unable to achieve non-reciprocal liquid manipulation. Constructing devices that can achieve non-reciprocal optofluidic control is of great value to the expansion of optofluidic devices in the application market. Summary of the Invention
[0004] The present invention aims to address the inability of existing optofluidic devices to achieve nonreciprocal fluid manipulation. By stacking multiple layers of asymmetric plasmonic nanodisks, asymmetric heat transfer paths are constructed. When light is irradiated from the forward and backward directions, photoexcitation and heat transfer occur along different heat transfer paths, generating opposite temperature gradients. This results in different fluid convection induced by the device under forward and backward illumination, achieving nonreciprocal fluid control.
[0005] In order to achieve the above-mentioned purpose, the present invention specifically adopts the following technical solutions:
[0006] A non-reciprocal optofluidic device comprises: a base layer and a first disk tower and a second disk tower arranged above the base layer, wherein the first disk tower and the second disk tower are both multi-layer structures with the same number of layers and each layer being arranged in a corresponding manner, and the same layer of the first disk tower and the second disk tower forms a heterodimer structure. When the diameter of a layer on the first disk tower is larger, the diameter of the corresponding layer on the second disk tower is smaller; when the diameter of a layer on the first disk tower is smaller, the diameter of the corresponding layer on the second disk tower is larger.
[0007] Furthermore, the base layer is glass, and the heterodimer structures located on the same layer of the first disc tower and the second disc tower are made of the same material, which is plasmon noble metal or dielectric material.
[0008] Furthermore, the plasmon noble metal material is either Au or Ag, and the dielectric material is either SiO2 or Al2O3.
[0009] Furthermore, the first disc tower and the second disc tower include a three-layer structure, which includes a first metal layer, a first spacer layer and a second metal layer from bottom to top.
[0010] Furthermore, the first disc tower and the second disc tower include a seven-layer structure, which includes, from bottom to top, a first metal layer, a first spacer layer, a second metal layer, a second spacer layer, a third metal layer, a third spacer layer, and a fourth metal layer.
[0011] Furthermore, the heterodimer structure located in the same layer is composed of a first nanodisc and a second nanodisc with different diameters.
[0012] Furthermore, the diameter of the first nanodisc is 120 to 200 nanometers, and the diameter of the second nanodisc is 200 to 280 nanometers.
[0013] Furthermore, the thickness of all metal layers is 20 to 40 nanometers, and the thickness of all spacer layers is 10 to 20 nanometers.
[0014] Furthermore, the first metal layer, the first spacer layer, the third metal layer, and the third spacer layer have the same structure; the second metal layer, the second spacer layer, and the fourth metal layer have the same structure.
[0015] Also provided is an application of an optofluidic device for realizing non-reciprocal particle manipulation.
[0016] Compared with the prior art, the advantages of the present invention are:
[0017] 1. The present invention provides a device for achieving non-reciprocal optofluidics. By stacking multiple layers of asymmetric plasmon nanodisks to construct an asymmetric heat transfer path, when light is irradiated from the forward and backward directions, light excitation and heat transfer occur on different heat transfer paths, generating opposite temperature gradients. As a result, the device induces different fluid convection under forward and backward illumination, achieving non-reciprocal fluid control. The device is simple and convenient, avoiding the complex technical means required by traditional non-reciprocal devices, such as the need for an external magnetic field, nonlinearity, or spatiotemporal modulation of the dielectric constant of the material. Non-reciprocity is achieved by simply stacking multiple layers of asymmetric disks to construct an asymmetric heat transfer path.
[0018] The optofluidic device of the present invention is composed of a multi-layer plasmon nanostructure, has a simple structure, can be directly prepared by combining electron beam etching, electron beam evaporation coating, and stripping processes, and is easy to prepare.
[0019] 2. The optofluidic device of the present invention can be used to achieve non-reciprocal particle manipulation, such as particle transport and particle separation, and has very broad application prospects in biosensing, drug detection, and other fields. BRIEF DESCRIPTION OF THE DRAWINGS
[0020] Figure 1 A schematic diagram of a device for implementing non-reciprocal optofluidics provided in this application;
[0021] Figure 2 A schematic side view (yz cross section or xz cross section) of a device for implementing non-reciprocal optofluidics provided in the present application;
[0022] Figure 3 A schematic diagram of the working principle of a device for implementing non-reciprocal optofluidics provided in this application;
[0023] Figure 4 A schematic diagram of non-reciprocal fluid control in a 50% glycerol-water solution of a device for realizing non-reciprocal optofluidics provided in this application;
[0024] Figure 5 Schematic diagram of non-reciprocal fluid control in water and magnetic fluid for a device that implements non-reciprocal optofluidics provided in this application;
[0025] Figure 6 A schematic diagram of an application of a device for implementing non-reciprocal optofluidics in particle separation provided by the present application;
[0026] Figure annotation:
[0027] Figure 1 :1-base layer; 2-first disc tower; 3-second disc tower;
[0028] Figure 2 :4-first metal layer; 5-second metal layer; 6-third metal layer; 7-fourth metal layer; 8-first spacer layer; 9-second spacer layer; 10-third spacer layer.
[0029] In order to make the purpose, 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 and completely described below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments.
[0030] Therefore, the detailed description of the embodiments of the present invention provided below is not intended to limit the scope of the claimed invention, but rather merely represents selected embodiments of the present invention. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without creative effort are intended to fall within the scope of protection of the present invention. DETAILED DESCRIPTION
[0031] The present invention provides a device for realizing non-reciprocal optical flow control. Figure 1 and Figure 2 , including: a base layer and a first disc tower and a second disc tower arranged above the base layer, the first disc tower and the second disc tower are both multi-layer structures with the same number of layers and each layer is arranged correspondingly, the same layer of the first disc tower and the second disc tower forms a heterodimer structure, when the diameter of a certain layer on the first disc tower is larger, the diameter of the corresponding layer on the second disc tower is smaller; when the diameter of a certain layer on the first disc tower is smaller, the diameter of the corresponding layer on the second disc tower is larger.
[0032] It can be understood that the first disc tower and the second disc tower are arranged on the base layer, and the first disc tower and the second disc tower are arranged to be a structure formed by stacking multiple layers of heterodimer structures. When the diameter of a layer on the first disc tower is larger, the diameter of the corresponding layer on the second disc tower is smaller; when the diameter of a layer on the first disc tower is smaller, the diameter of the corresponding layer on the second disc tower is larger; this structure can construct an asymmetric heat transfer path. When light is irradiated from the forward direction and the backward direction, light excitation and heat transfer occur on different heat transfer paths, generating opposite temperature gradients, so that the fluid convection induced by the device under forward irradiation and backward irradiation is different, thereby realizing non-reciprocal fluid control.
[0033] This device is simple and convenient, avoiding the complex technical methods required by traditional non-reciprocal devices, such as external magnetic fields, nonlinearity, or spatiotemporal modulation of the dielectric constant of the material. Non-reciprocity is achieved simply by stacking multiple layers of asymmetric disks to create an asymmetric heat transfer path.
[0034] The non-reciprocal optofluidic device of the present invention is composed of a multi-layer plasmon nanostructure, has a simple structure, can be directly prepared by combining electron beam etching, electron beam evaporation coating, and lift-off processes, and is easy to prepare.
[0035] In certain embodiments of the present invention, the base layer is made of glass, and the heterodimer structures located on the same layer of the first and second disk towers are made of the same material, namely, plasmonic noble metals or dielectric materials. It should be noted that the materials of the adjacent upper and lower heterodimer structures are different.
[0036] In some embodiments of the present invention, the plasmon noble metal material is either Au or Ag, and the dielectric material is either SiO 2 or Al 2 O 3 .
[0037] Specifically, the plasmon noble metal material is preferably Au, and the dielectric material is preferably SiO 2 .
[0038] In certain embodiments of the present invention, see Figure 2 The first disc tower and the second disc tower include a seven-layer structure, which includes, from bottom to top, a first metal layer 4, a first spacer layer 8, a second metal layer 5, a second spacer layer 9, a third metal layer 6, a third spacer layer 10, and a fourth metal layer 7.
[0039] In certain embodiments of the present invention, the heterodimer structures located in the same layer are composed of a first nanodisc and a second nanodisc with different diameters.
[0040] In some embodiments of the present invention, the diameter of the first nanodisc is 120-200 nanometers, and the diameter of the second nanodisc is 200-280 nanometers.
[0041] Specifically, the diameter of the first nanodisc is preferably 160 nanometers, and the diameter of the second nanodisc is 240 meters.
[0042] It can be understood that by providing first and second nanodisks of different diameters, two asymmetric heat sources are constructed, and by stacking multiple heterodimer structure layers, two different heat transfer paths are constructed.
[0043] Furthermore, the two adjacent metal layers (the two metal layers closest to each other) that make up the first and second disc towers are rotationally symmetrical. This arrangement allows us to construct two asymmetric heat transfer paths: path A (i.e., the path formed by the first disc tower) and path B (i.e., the path formed by the second disc tower). The top layer of heat transfer path A (i.e., the path formed by the first disc tower) is the first nanodisk, while the bottom layer of heat transfer path B (i.e., the path formed by the second disc tower) is the first nanodisk.
[0044] Specifically, see, for example, Figure 2 In the first metal layer 4, the second nanodisc is located on the left (i.e., on the first disk tower), and the first nanodisc is located on the right (i.e., on the second disk tower). The opposite is true for the second metal layer 5 adjacent to the first metal layer 4: the second nanodisc is located on the left (i.e., on the first disk tower), and the first nanodisc is located on the right (i.e., on the second disk tower). This means that the two adjacent metal layers are rotationally symmetrical.
[0045] When we use the resonant frequency of the first nanodisk as the frequency of the excitation light, the light is irradiated from the front (i.e., the light is irradiated from above the solution), and the optical excitation mainly occurs on the first nanodisk in the top metal layer (i.e., the fourth metal layer 7). Subsequently, the heat transfer mainly occurs on the heat transfer path A on the top side of the first nanodisk (i.e., the path formed by the first nanodisk tower). On the contrary, when the light is irradiated from the back (i.e., the light is irradiated from below the substrate), the optical excitation mainly occurs in the bottom metal layer (i.e., the first metal layer 4). On the first nanodisk, heat transfer then mainly occurs on the heat transfer path B on the bottom layer of the first nanodisk side (i.e., the path formed by the second disk tower); therefore, when light irradiates the device from the front (i.e., light irradiates the device from above the solution) and from the back (i.e., light irradiates the device from below the substrate layer), light excitation and heat transfer occur on different heat transfer paths, resulting in different temperature gradients in the device under the two excitation conditions, thereby inducing different fluid convection, and ultimately enabling the device to achieve non-reciprocal fluid control.
[0046] In certain embodiments of the present invention, the first and second circular disk towers comprise a three-layer structure, comprising, from bottom to top, a first metal layer, a first spacer layer, and a second metal layer. It should be noted that this three-layer optofluidic device can achieve the same performance as a seven-layer optofluidic device, but with superior performance.
[0047] In some embodiments of the present invention, the thickness of all metal layers is 20-40 nanometers, and the thickness of all spacer layers is 10-20 nanometers.
[0048] Specifically, the thickness of all metal layers is preferably 30 nanometers, and the thickness of all spacer layers is preferably 15 nanometers.
[0049] Understandably, please combine Figure 2 The thickness of the first metal layer 4, the second metal layer 5, the third metal layer 6 and the fourth metal layer 7 is 20 to 40 nanometers, and the thickness of the first spacer layer 8, the second spacer layer 9 and the third spacer layer 10 is 10 to 20 nanometers. This arrangement further enables the obtained stacking structure to construct an asymmetric heat transfer path, thereby achieving non-reciprocity.
[0050] In some embodiments of the present invention, the first metal layer 4, the first spacer layer 8, the third metal layer 6, and the third spacer layer 10 have the same structure; the second metal layer 5, the second spacer layer 9, and the fourth metal layer 7 have the same structure.
[0051] The structure of the first metal layer 4 , the first spacer layer 8 , the third metal layer 6 , and the third spacer layer 10 is as follows: the second nanodisk is on the left, and the first nanodisk is on the right.
[0052] The structures of the second metal layer 5 , the second spacer layer 9 and the fourth metal layer 7 are as follows: the first nanodisk is on the left and the second nanodisk is on the right.
[0053] It can be seen that such a structural arrangement is that the two upper and lower adjacent metal layers (the two metal layers closest to each other) constituting the first disc tower and the second disc tower described above are in a central rotationally symmetrical relationship.
[0054] Also provided is an application of a device for realizing non-reciprocal optofluidics, wherein the optofluidics device is used to realize non-reciprocal particle manipulation.
[0055] In certain embodiments of the present invention, a device implementing nonreciprocal optofluidics is placed in a liquid-filled chamber containing dispersed nanoparticles. When a 1090-nm laser is irradiated from the front (i.e., the light illuminates the device from above the solution), the nanoparticles accumulate on one side of the chamber. When a 1090-nm laser is irradiated from the back (i.e., the light illuminates the device from below the substrate), the nanoparticles accumulate on the other side of the chamber. This device achieves both nanoparticle transport and separation, and has broad application prospects in biosensing, drug detection, and other fields.
[0056] Example 1
[0057] This embodiment simulates and calculates a device for realizing non-reciprocal optofluidics of the present invention. The liquid surrounding the device is set to a glycerol-water solution with a concentration of 50%, and the solution height is set to 1.5 microns. The device is illuminated by 1090 nm excitation light from the forward direction (i.e., the light illuminates the device from above the solution) and the backward direction (i.e., the light illuminates the device from below the substrate layer), and the following results are obtained: Figure 4 The schematic diagram of non-reciprocal fluid control is shown in the figure, and the schematic diagram of its working principle is shown in the figure. Figure 3 shown.
[0058] Specifically, Figure 4Figures a and b are schematic diagrams of the fluid convection control of the non-reciprocal optofluidic device under forward and backward illumination at times of 10 nanoseconds, 100 nanoseconds, 1000 nanoseconds, and 10,000 nanoseconds, respectively. It can be seen that under forward illumination (i.e., light irradiates the device from above the solution), the first nanodisk of the topmost metal layer resonates, and then heat transfer mainly occurs on the first disk tower structure (i.e., the top layer is the heat transfer path A on the side of the first nanodisk), while there is almost no heat generation and transfer on the second disk tower structure, causing the device to produce a temperature gradient with a high left and a low right. Subsequently, the heat energy is dissipated from the device to the surrounding liquid through thermal radiation and heat conduction, generating a local temperature gradient with a high left and a low right in the liquid, causing the liquid density to present a distribution with a high right and a low left. Ultimately, fluid thermal convection is induced in the surrounding liquid.
[0059] Under backward illumination (i.e., light irradiating the device from below the substrate), the first nanodisk in the bottom metal layer resonates. Subsequently, heat transfer occurs primarily along the second nanodisk tower structure (i.e., along heat transfer path B on the bottom side of the first nanodisk). Almost no heat is generated or transferred along the first nanodisk tower structure, resulting in a temperature gradient with a high right and a low left. Next, heat energy dissipates from the device into the surrounding liquid through thermal radiation and conduction, generating a localized temperature gradient with a low left and a high right, causing the liquid density to exhibit a low right and high left distribution. Ultimately, fluid thermal convection occurs in the surrounding liquid in the opposite direction to that under forward illumination, thus achieving non-reciprocal fluid control.
[0060] Effect Example 1 Quantifying the non-reciprocity of the device for realizing non-reciprocal optofluidics of the present invention
[0061] In order to further quantify the non-reciprocity of the device for realizing non-reciprocal optofluidics of the present invention, Figure 4 c and d show the temperature and fluid velocity as a function of irradiation time for forward irradiation and backward irradiation.
[0062] according to Figure 4 From c and d, we can see that with the increase of irradiation time, the non-reciprocal temperature and flow rate first gradually increase, and then when the system reaches a steady state, the non-reciprocal temperature and flow rate basically remain stable.
[0063] Effect Example 2 Verifies the Wide Applicability of the Device for Implementing Non-reciprocal Optofluidics
[0064] In order to verify the wide applicability of the device for realizing non-reciprocal optofluidics of the present invention, this embodiment also simulates and calculates the non-reciprocal fluid manipulation characteristics of the device for realizing non-reciprocal optofluidics of the present invention in other liquids, such as Figure 5 shown.
[0065] Figure 5a and b are the non-reciprocal fluid manipulation characteristics of the device for realizing non-reciprocal optofluidics in water when the system reaches a steady state. Figure 5 a is the temperature and flow rate distribution of the optofluidic device when irradiated in the forward direction (i.e., light irradiates the device from above the solution), Figure 5 Figure b shows the temperature and flow velocity distribution of the optofluidic device under backward illumination (i.e., light irradiating the device from below the substrate). It can be seen that when the device is illuminated from the front (i.e., light irradiating the device from above the solution), the temperature is primarily concentrated in the first disk-tower structure (i.e., heat transfer path A on the top side of the first nanodisk), while when the device is illuminated from the back (i.e., light irradiating the device from below the substrate), the temperature is primarily concentrated in the second disk-tower structure (i.e., heat transfer path B on the bottom side of the first nanodisk), resulting in different fluid convection distributions.
[0066] Figure 5 c and d are the non-reciprocal fluid control characteristics of the device for realizing non-reciprocal optical fluidic control in the magnetic fluid when the system reaches a steady state. Figure 5 c is the temperature and flow rate distribution of the optofluidic device when irradiated in the forward direction (i.e., the light irradiates the device from above the solution), Figure 5 d is the temperature and flow velocity distribution diagram of the optofluidic device when backward illumination is applied (i.e., light is applied to the device from below the substrate layer).
[0067] Similarly, it can be found that when irradiated in the forward direction (i.e., when light illuminates the device from above the solution), the device's temperature is primarily concentrated in the first disk-tower structure (i.e., heat transfer path A on the uppermost layer, the first nanodisk side), while when irradiated in the backward direction (i.e., when light illuminates the device from below the substrate layer), the temperature is primarily concentrated in the second disk-tower structure (i.e., heat transfer path B on the lowermost layer, the first nanodisk side), resulting in different fluid convection distributions. Thus, we can demonstrate that the device can be widely used in other liquid environments. Therefore, the device for achieving nonreciprocal optofluidics involved in this case has broad applicability.
[0068] Effect Example 3: Application of devices that realize non-reciprocal optical fluidics
[0069] Based on the device for implementing non-reciprocal optofluidics provided in Example 1, this embodiment provides an application of the device for implementing non-reciprocal optofluidics.
[0070] See also Figure 6Figure 2 shows a schematic diagram of a device that implements non-reciprocal optofluidics for particle separation. The non-reciprocal optofluidic device is placed in a liquid-filled chamber. Nanoparticle pellets are initially released at the center of the device. When a 1090-nm laser is irradiated from the front (i.e., the light illuminates the device from above the solution), the nanoparticle pellets gather on the right side of the chamber as the irradiation time increases. When a 1090-nm laser is irradiated from the back (i.e., the light illuminates the device from below the substrate layer), the nanoparticle pellets gather on the left side of the chamber as the irradiation time increases. This allows us to separate nanoparticles.
[0071] The above embodiment is merely one embodiment of the present invention, and its description is relatively specific and detailed, but it should not be construed as limiting the scope of the present invention. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the scope of the present invention, and these modifications and improvements fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be based on the appended claims.
Claims
1. A device for realizing non-reciprocal optofluidics, characterized in that: include: The base layer and the first disc tower and the second disc tower arranged above the base layer, the first disc tower and the second disc tower are both multi-layer structures with the same number of layers and corresponding arrangements of each layer, the same layer of the first disc tower and the second disc tower forms a heterodimer structure, when the diameter of a certain layer on the first disc tower is larger, the diameter of the corresponding layer on the second disc tower is smaller; when the diameter of a certain layer on the first disc tower is smaller, the diameter of the corresponding layer on the second disc tower is larger; the first disc tower and the second disc tower include a seven-layer structure, including, from bottom to top, a first metal layer, a first spacer layer, a second metal layer, a second spacer layer, a third metal layer, a third spacer layer, and a fourth metal layer; the upper and lower adjacent metal layers constituting the first disc tower and the second disc tower are in a central rotationally symmetrical relationship; the structures of the first metal layer, the first spacer layer, the third metal layer, and the third spacer layer are the same, and the structures of the second metal layer, the second spacer layer, and the fourth metal layer are the same.
2. The device for implementing non-reciprocal optofluidics according to claim 1, characterized in that: The base layer is made of glass, and the heterodimer structures located on the same layer of the first disc tower and the second disc tower are made of the same material, which is plasmon noble metal or dielectric material.
3. The device for implementing non-reciprocal optofluidics according to claim 2, characterized in that: The plasmon noble metal is Au or Ag, and the dielectric material is SiO2 or Al2O3.
4. The device for implementing non-reciprocal optofluidics according to claim 1, characterized in that: The heterodimer structures located in the same layer are composed of a first nanodisc and a second nanodisc with different diameters.
5. The device for implementing non-reciprocal optofluidics according to claim 4, characterized in that: The diameter of the first nanodisc is 120-200 nanometers, and the diameter of the second nanodisc is 200-280 nanometers.
6. The device for implementing non-reciprocal optofluidics according to claim 5, characterized in that: The thickness of all metal layers is 20-40 nanometers, and the thickness of all spacer layers is 10-20 nanometers.
7. Application of a device for realizing non-reciprocal optofluidics according to any one of claims 1 to 6, characterized in that: The optofluidic device is used to achieve non-reciprocal particle manipulation.