Method for rotating photo-real-time controllable zinc oxide microrods

Abstract

The application discloses a method for rotating a light real-time controllable zinc oxide microrod. The method is realized by interaction between a spatial electric field generated by focusing laser irradiation on lithium niobate and a zinc oxide microrod, so that the zinc oxide microrod moves in a two-dimensional plane. By adjusting different end face positions of the zinc oxide microrod irradiated by the laser, the rotating direction of the zinc oxide microrod in the two-dimensional plane can be effectively controlled, and the rotating speed is controllable. In addition, by adjusting the laser intensity or changing the length of the zinc oxide microrod, the rotation of the zinc oxide microrod in a three-dimensional space is also successfully realized. The method has important significance for research and development of micro-lasers and integration of photonics chips.

Description

Technical Field

[0001] This invention relates to a technology for real-time controllable rotation of zinc oxide microrods, specifically a technology that utilizes the interaction between the spatial electric field generated by laser irradiation of lithium niobate and the zinc oxide microrod to achieve the movement of the zinc oxide microrod in a two-dimensional plane and its rotation in two-dimensional plane and three-dimensional space. Background Technology

[0002] Microfluidic chip technology is a technique for manipulating targets at the micrometer scale. In recent years, with the miniaturization and integration of devices, the manipulation of micrometer-scale targets has become a research hotspot. However, currently, most manipulation of micrometer-scale rigid targets requires the manipulated target to have a regular shape, and research on the manipulation of irregularly shaped rigid targets is relatively limited. This patent proposes a method for real-time optically controllable rotation of zinc oxide microrods. First, by adjusting the laser irradiation position, the directional movement of the zinc oxide microrod in a two-dimensional plane is achieved. Second, by adjusting the laser irradiation on different end faces of the zinc oxide microrod, the directional rotation of the zinc oxide microrod is achieved. Finally, by adjusting the laser intensity and the length of the microrod, the directional rotation of the microrod in three-dimensional space can be achieved. This manipulation technology plays an important role in the future development of photonic integrated chip devices.

[0003] In 2005, Chiou PY et al. prepared a thin film of hydrogenated amorphous silicon (a-Si:H) on ITO glass. Under the action of an external electric field, laser irradiation creates a non-uniform electric field on the chip, which they then used to manipulate cells.

[0004] In 2015, Flores-Flores E et al. dispersed silicon particles in an aqueous solution and then used the temperature gradient generated by laser irradiation to induce convection, thus capturing the silicon particles. This manipulation method is relatively simple, and the manipulated target has a regular geometric shape.

[0005] In 2018, Lin LH et al. dispersed PS nanospheres in an aqueous solution containing a cationic surfactant. The cationic surfactant adsorbed onto the particle surface, giving the particles a positive charge. They then used a focused laser to irradiate a substrate coated with a metal film. The metal film absorbed the laser heat, creating a temperature gradient. Since cations and anions in the aqueous solution have different thermal mobility—cations have higher thermal mobility and move away from the high-temperature region, while anions have lower thermal mobility and remain in situ—an electric field is generated locally in the aqueous solution. This electric field exerts a Coulomb force on the particles, enabling manipulation of the nanoparticles. Summary of the Invention

[0006] Current reported methods for manipulating micro- and nano-sized targets still face many limitations, such as the requirement that the manipulated targets mostly have regular shapes and relatively limited manipulation modes. To address these issues, this invention provides a simple and reliable method for manipulating zinc oxide microrods. This method utilizes the spatial electric field generated by laser irradiation of lithium niobate to control the movement of the zinc oxide microrod in a two-dimensional plane and its rotation in both two-dimensional and three-dimensional space. Furthermore, the direction of movement, position, and rotation angle of the zinc oxide microrod are all controlled by the laser throughout the experimental process, thus this method features precise manipulation and high reliability.

[0007] A method for real-time optically controllable rotation of zinc oxide microrods is characterized by: using a lithium niobate chip as a substrate and transformer oil as the environmental medium, dispersing zinc oxide microrods in the transformer oil. Subsequently, the transformer oil containing the dispersed zinc oxide microrods is placed on the lithium niobate chip, and the rotation of the zinc oxide microrods is achieved by utilizing the interaction between the spatial electric field generated by laser irradiation of lithium niobate and the zinc oxide microrods.

[0008] According to claim 1, a method for real-time controllable rotation of zinc oxide microrods is characterized in that: by changing different end faces of the zinc oxide microrod irradiated by laser, clockwise and counterclockwise rotation of the zinc oxide microrod in a two-dimensional plane can be achieved, and the rotation angle and speed are controllable.

[0009] According to claim 1, a method for real-time controllable rotation of zinc oxide microrods is characterized in that: by adjusting the laser intensity or changing the length of the zinc oxide microrod, the rotation of the zinc oxide microrod in three-dimensional space is successfully achieved.

[0010] Compared with existing technologies, the advantages of this invention are as follows: First, using a single lithium niobate sheet as a substrate, the movement and rotation of the microrod are achieved by utilizing the interaction between the spatial electric field generated by laser irradiation of lithium niobate and the zinc oxide microrod. Furthermore, clockwise and counterclockwise rotation of the microrod in a two-dimensional plane can be achieved by changing the position of the laser-irradiated end face of the zinc oxide microrod, and the rotation angle and speed are controllable. In addition, rotation of the zinc oxide microrod in three-dimensional space can be achieved by adjusting the laser intensity or changing the length of the zinc oxide microrod. Second, we utilize focused lasers to achieve active and reliable manipulation (movement and rotation) of irregularly shaped targets. Attached Figure Description

[0011] Figure 1 This is a schematic diagram of the overall structure of the device for moving and rotating zinc oxide microrods by using focused laser irradiation of lithium niobate according to the present invention.

[0012] Figure 2 This is a process diagram of one embodiment (Example 1) of the present invention, which utilizes focused laser irradiation of lithium niobate to realize the movement of zinc oxide microrods in a two-dimensional plane.

[0013] Figure 3 This is a process diagram of one embodiment (Example 2) of the present invention, which utilizes focused laser irradiation of lithium niobate to achieve clockwise rotation of zinc oxide microrods in a two-dimensional plane.

[0014] Figure 4 This is a process diagram of one embodiment (Example 3) of the present invention, which utilizes focused laser irradiation of lithium niobate to achieve counterclockwise rotation of zinc oxide microrods in a two-dimensional plane.

[0015] Figure 5 This is a process diagram of one embodiment (Example 4) of the present invention, which utilizes focused laser irradiation of lithium niobate to achieve three-dimensional spatial rotation of zinc oxide microrods. Detailed Implementation

[0016] The present invention will be further described below with reference to embodiments and accompanying drawings.

[0017] This invention discloses a method for real-time optically controllable rotation of zinc oxide microrods. The device includes: a laser 1, an electronic shutter 2, a laser mirror 3, a focusing lens 4, a lithium niobate chip 5, a background light source 6, a filter 7, and a CCD camera 8.

[0018] This invention discloses a method for real-time controllable rotation of zinc oxide microrods. The method involves the following steps: dispersing zinc oxide microrods in an insulating medium (transformer oil); placing the transformer oil containing the dispersed zinc oxide microrods on a lithium niobate chip 5; adjusting the objective lens position using a stepper motor to accurately focus the incident laser onto the lithium niobate chip; capturing a clear image using a CCD camera; adjusting the laser power and opening the electronic shutter; reflecting the laser beam through a laser mirror into the focusing objective lens and focusing it onto the lithium niobate chip; and generating a spatial electric field by irradiating the lithium niobate chip with the laser, causing the zinc oxide microrods to move and rotate under the influence of this electric field. By changing the position of the laser-irradiated end face of the zinc oxide microrods, directional movement and rotation of the microrods in a two-dimensional plane can be achieved, and the direction, position, and angle of movement are all controllable. Furthermore, by adjusting the laser intensity or changing the length of the zinc oxide microrods, rotation of the zinc oxide microrods in three-dimensional space can be achieved.

[0019] Taking into account the above and the cost of components and the observation effect, the preferred range of parameters is as follows: laser 1 wavelength is 400-500nm, background light source 6 is a halogen lamp, and objective lens 4 magnification is 100x. To ensure correct light propagation and measurement accuracy, all optical components and electronic devices in the optical path are fixed on a rigid connecting frame.

[0020] The working principle of this invention is as follows: The spatial electric field generated by laser irradiation of lithium niobate interacts with the zinc oxide microrod. The force mode experienced by the zinc oxide microrod varies depending on the laser irradiation position. Therefore, by adjusting the laser irradiation position, directional movement and rotation of the zinc oxide microrod within a two-dimensional plane can be achieved. Furthermore, adjusting the laser intensity or changing the length of the zinc oxide microrod can also alter its force mode. By controlling these parameters, rotation of the microrod in three-dimensional space has also been successfully achieved.

[0021] The following are specific embodiments of the present invention that utilize focused laser to achieve the rotation of zinc oxide microrods. These specific embodiments are only used to illustrate the present invention in detail and do not limit the scope of protection of the claims of this application.

[0022] Example 1

[0023] A 473nm laser with a power of 100μW was used, with a halogen lamp as the background light source and a focusing objective with magnification of 100x. Transformer oil containing dispersed zinc oxide microrods, each 20 micrometers in length, was placed on a lithium niobate sheet. The laser irradiated the area around the zinc oxide microrods, and the movement of the microrods due to the change in their laser irradiation position was achieved by adjusting the laser irradiation position using a motor.

[0024] Example 2

[0025] A 473nm laser with a power of 100μW was used, with a halogen lamp as the background light source and a focusing objective with a magnification of 100x. Transformer oil containing zinc oxide microrods, each 20 micrometers in length, was placed on a lithium niobate sheet. The laser irradiation position was adjusted by a motor. First, the laser irradiated one end face of the zinc oxide microrod, achieving clockwise rotation of the microrod.

[0026] Example 3

[0027] A 473nm laser with a power of 100μW was used, with a halogen lamp as the background light source and a focusing objective with a magnification of 100x. Transformer oil containing zinc oxide microrods, each 20 micrometers in length, was placed on a lithium niobate sheet. By adjusting the objective position and opening the electronic shutter, the laser irradiated the other end of the zinc oxide microrods, achieving a counterclockwise rotation of the microrods.

[0028] Example 4

[0029] A 473nm laser with a power of 100μW was used, with a halogen lamp as the background light source and a focusing objective with a magnification of 100x. Transformer oil containing dispersed zinc oxide microrods, each 12 micrometers in length, was placed on a lithium niobate chip. By adjusting the laser irradiation position so that the focused laser irradiated one end face of the zinc oxide microrod, rotation of the zinc oxide microrod in three-dimensional space was achieved.

Claims

1. A method for real-time optically controllable rotation of zinc oxide microrods, characterized in that: Using a lithium niobate chip as a substrate and transformer oil as the environmental medium, zinc oxide microrods are dispersed in the transformer oil. Subsequently, the transformer oil containing the dispersed zinc oxide microrods is placed on the lithium niobate chip, and the rotation of the zinc oxide microrods is achieved by the interaction between the spatial electric field generated by laser irradiation of lithium niobate and the zinc oxide microrods.

2. The method for real-time controllable rotation of a zinc oxide microrod according to claim 1, characterized in that: By changing the different end faces of the zinc oxide microrod irradiated with laser, the zinc oxide microrod can be rotated clockwise and counterclockwise in a two-dimensional plane, and the rotation angle and speed are controllable.

3. The method for real-time controllable rotation of a zinc oxide microrod according to claim 1, characterized in that: By adjusting the laser intensity or changing the length of the zinc oxide microrod, the rotation of the zinc oxide microrod in three-dimensional space was successfully achieved.

Images