An InI photoelectric detection dominant response mechanism switching method based on pressure threshold regulation

Abstract

This invention discloses a method for switching the dominant response mechanism of InI photodetector based on pressure threshold modulation, relating to the field of optoelectronics. The method involves placing an InI sample and an electrode in a diamond anvil cell within a contact structure, and applying pressure to the sample under quasi-hydrostatic conditions. By adjusting the applied pressure to different threshold ranges, the crystal and electronic structures of InI change, thereby switching the dominant photodetector response mechanism between different modes. In the low-pressure range, InI is in a semiconductor state, and its photoelectric response is dominated by the photoconductive effect. When the pressure exceeds the set threshold, the InI bandgap compresses and tends towards a quasi-metallic state, its dominant response mechanism changes, and it exhibits a high photocurrent response. This invention achieves controllable switching of the photodetector mechanism through pressure threshold modulation, elevating external field modulation from performance enhancement to working mechanism modulation, and has the advantages of simple modulation method, strong controllability, and good scalability.

Description

Technical Field

[0001] This invention relates to the field of optoelectronic materials and devices, and more specifically, to a method for switching the dominant response mechanism of InI photodetector based on pressure threshold modulation. Background Technology

[0002] InI, as a two-dimensional layered semiconductor material with potential optoelectronic applications, has attracted attention in the field of photoelectric detection. However, under normal pressure conditions, its photoelectric response is usually limited by its intrinsic band gap and carrier transport capacity, making it difficult to achieve high sensitivity and wide-spectrum detection.

[0003] In the existing technology, photoelectric performance is usually improved by methods such as material doping, interface engineering or device structure design. However, the above methods are often complex and the control method is fixed, making it difficult to achieve dynamic control of the working state of photoelectric detection.

[0004] On the other hand, external field manipulation (such as pressure and electric fields) can alter the electronic structure of materials and affect their photoelectric response behavior. However, existing research mainly focuses on performance enhancement phenomena such as photocurrent enhancement or bandgap changes, lacking technical solutions for controllable adjustment of the dominant response mechanism of photoelectric detection. Therefore, how to elevate external field manipulation from superficial performance enhancement to operational mechanism control, achieving controllable switching of the photoelectric detection response mechanism, and thus reconstructing the device's operating mode, has become an urgent problem to be solved in this field. Summary of the Invention

[0005] Therefore, this invention provides a method for switching the dominant response mechanism of InI photoelectric detection based on pressure threshold regulation, so as to achieve controllable adjustment of the dominant response mechanism of photoelectric detection. To achieve the above objective, the proposed solution is as follows:

[0006] An InI sample was formed into an electrical contact structure with an electrode and placed in a diamond anvil cell. Pressure was applied under quasi-hydrostatic conditions and the pressure was adjusted to be in different pressure ranges.

[0007] In the low-pressure range, InI is in the semiconductor state, and its photoelectric response is dominated by the photoconductive effect;

[0008] When the pressure exceeds the preset threshold, the InI crystal structure and electronic structure are reconstructed, the band gap is compressed and tends to a quasi-metallic state, which changes the photoelectric detection-dominant response mechanism and thus enters the second response mode.

[0009] Preferably, the pressure threshold corresponds to the pressure range in which the InI Raman characteristic peak changes significantly.

[0010] Compared with the prior art, the present invention has at least the following beneficial effects:

[0011] This invention achieves the switching of the dominant response mechanism of InI photodetector from photoconductive response in the low-pressure region to non-interband dominant response in the high-pressure region by setting a pressure threshold range. This method can reconstruct the working mode of photodetector without relying on material doping or complex structure design, thereby upgrading the external field control from traditional performance enhancement to working mechanism control, with good controllability and scalability. Attached Figure Description

[0012] Figure 1 This is a basic schematic diagram of a diamond anvil cell press provided in an embodiment of the present invention;

[0013] Figure 2 The photocurrent versus pressure curve during the pressurization process provided in this embodiment of the invention;

[0014] Figure 3 The in-situ Raman spectrum during the pressurization process provided in this embodiment of the invention;

[0015] Figure 4 The resistance versus pressure curve during the pressurization process is provided in an embodiment of the present invention;

[0016] Explanation of reference numerals in the attached figures:

[0017] 1—Diamond anvil cell; 2—InI sample; 3—Electrode; 4—Sealing gasket; 5—Ruby; 6—Excitation source. Detailed Implementation

[0018] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] First, the high-voltage photoelectric response testing device is introduced, among which... Figure 1This is a schematic diagram of the high-pressure loading device used in this embodiment of the invention. It includes a diamond anvil cell 1, an InI sample 2 in the sample chamber, a contact electrode 3, a sealing gasket 4, a ruby ​​5, and an excitation light source 6. It can be seen that the pressure is generated by the compression of two opposing diamonds. Specifically, the sealing gasket 4, after pre-compression, forms the sample chamber, with the InI sample 2 placed at the center. Electrodes 3 are positioned on both sides of the sample, forming an electrical contact structure with the InI sample for electrical transport and photocurrent signal acquisition. The electrodes are led out of the diamond anvil cell device via wires and connected to an external electrical testing system. The ruby ​​5 is also placed in the sample chamber for pressure calibration using ruby ​​fluorescence, thereby achieving accurate measurement of the actual pressure state of the sample. During the test, the excitation light source 6 enters the sample area through the diamond window, illuminating and exciting the InI sample to generate a photocurrent response signal. By adjusting the loading force of the diamond anvil cell 1, a continuous and controllable pressure can be applied to the InI sample 2 in the sample chamber, placing it in different pressure ranges, thereby studying its photoelectric response behavior under different pressure conditions.

[0020] Through the above-described device structure, the synergistic effect of pressure regulation, photoexcitation, and electrical signal detection can be achieved in the same experimental system, thereby providing a structural basis for the switching of the photoelectric detection-dominant response mechanism based on pressure threshold in this invention.

[0021] During the experiment, the applied pressure was continuously varied within the range of 0 to 25 GPa by gradually adjusting the loading force of the diamond anvil cell, and the photocurrent and structural changes under different pressures were recorded. Throughout the process, the sample was kept in a quasi-hydrostatic environment to ensure that the pressure was applied uniformly to the InI sample.

[0022] like Figure 2 The figure shows the relationship between the photocurrent of the InI sample and pressure. It can be observed that the photocurrent generally shows a significant increasing trend with increasing pressure, and exhibits a clear transition behavior in the 12-15 GPa range, indicating the existence of a pressure threshold. Specifically:

[0023] In the low-pressure range, the photocurrent response is weak and increases steadily with increasing pressure. At this time, the InI material maintains its semiconductor properties. Its photoelectric response mainly comes from the reduction of the band gap under pressure, which leads to the enhancement of light absorption capacity and improves the generation and transport of photogenerated carriers, corresponding to the photoconductivity-dominated response mechanism.

[0024] When the pressure exceeds the threshold, the photocurrent remains at a high level, and its change trend slows down significantly and tends to stabilize, forming a high response plateau state, exhibiting photoelectric response behavior that is significantly different from that in the low-pressure region.

[0025] Combination Figure 3The in-situ Raman spectroscopy results shown can be further analyzed. Within the range of approximately 12–17 GPa, the characteristic peaks of InI show a significant shift and peak shape reconstruction, indicating a significant change in the material's crystal structure. This structural change highly corresponds to the abrupt change in photocurrent, suggesting that the alteration in photoelectric response behavior is closely related to structural reconstruction.

[0026] Further integration Figure 4 The resistance-pressure curves shown indicate that the material resistance decreases significantly within the same pressure range, indicating a significant enhancement in carrier transport capability. This further confirms the transition of the material's electronic structure from a semiconductor state to a quasi-metallic state.

[0027] This indicates that in the low-pressure range, InI is in its first response mode, with the photoconductivity effect as the dominant response mechanism. The abrupt change in photocurrent corresponds to a synergistic change in the material's electronic structure and carrier transport mechanism, leading to a switch in the dominant photodetector response mechanism. When the pressure exceeds a preset threshold, the InI crystal structure and electronic structure are reconstructed, resulting in significant bandgap compression and even a tendency towards a quasi-metallic state. Figure 4 As shown in the resistance-pressure curve, the material resistance decreases significantly within this pressure range, while the carrier concentration and transport capacity are significantly enhanced, leading to an enhanced Joule heating effect under applied bias. Under illumination, this thermal effect further participates in the photoelectric response process, causing the device's photoelectric response mechanism to gradually shift from photoconductivity-dominated in the low-pressure region to a response mechanism dominated by non-band processes, including thermal effect response. At this point, the photocurrent remains at a high level and tends to stabilize, indicating that the device has entered the second response mode.

[0028] This demonstrates that, through pressure threshold regulation, the present invention not only achieves changes in photoelectric response intensity but also switches the photoelectric detection dominant response mechanism from photoconductive response to non-interband dominant response, thereby enabling controllable reconfiguration of the device's operating mode.

[0029] Finally, it should be noted that in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0030] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0031] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for switching the dominant response mechanism of InI photoelectric detection based on pressure threshold regulation, characterized in that, Includes the following steps: The InI sample is placed in the sample cavity of a diamond anvil cell that has been aligned, and the electrode forms an electrical contact structure with the InI sample. Under quasi-static water pressure conditions, compressive stress was applied to the InI sample, and the applied pressure was adjusted to be within different pressure ranges. By regulating the pressure, the crystal structure and electronic structure of InI change, thereby switching its photoelectric detection-dominant response mechanism between different modes, wherein: In the low-pressure range, InI is in first-response mode; When the pressure exceeds the preset pressure threshold, InI enters the second response mode, and the photocurrent response corresponding to the second response mode is significantly higher than that of the first response mode.

2. The method according to claim 1, characterized in that, The pressure threshold corresponds to the pressure range in which the InI crystal structure undergoes reconstruction.

3. The method according to claim 1, characterized in that, The first response mode is a response mode dominated by the photoconductive effect.

4. The method according to claim 1, characterized in that, The second response mode is a response mode dominated by non-inter-band transitions.

5. The method according to claim 4, characterized in that, The second response mode is a thermally-dominated optical response mode.

6. The method according to claim 1, characterized in that, The pressure loading range is 0 ~ 25 GPa.

7. The method according to claim 1, characterized in that, The quasi-hydrostatic pressure condition is achieved by filling the sample chamber with sodium chloride and inert gas.

8. The method according to claim 1, characterized in that, The electrode is a Pt electrode or an Au electrode.

9. The method according to claim 1, characterized in that, The switching of the response mechanism is characterized by Raman spectroscopy, charge transport properties, or abrupt changes in photocurrent with pressure.

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