Internally modulated terahertz source based on waveguide structure and its internal modulation method

Abstract

The invention discloses an internal modulation terahertz source based on a waveguide structure and an internal modulation method thereof. The internal modulation terahertz source comprises a pumping source, a laser beam combiner, a coupler and a waveguide structure, all of which are sequentially arranged, wherein the pumping source is composed of two independent fiber lasers; the waveguide structure is formed by tightly adhering an organic electro-optical material cladding, a lithium niobate core layer and a quartz substrate from top to bottom through optical cement, a control circuit is arranged in the organic electro-optical material cladding, and a wedge-shaped structure is arranged on the outer side of the organic electro-optical material cladding. The refractive index of the organic electro-optical material cladding is modulated through the control circuit, so that waveguide structure internal modulation terahertz output is obtained; therefore, the higher core layer internal energy conversion efficiency is achieved, and the generated terahertz energy can be efficiently coupled and outputted. According to the internal modulation terahertz source based on the waveguide structure and the internal modulation method thereof, integrated optical modulated terahertz radiation with high efficiency and a simple and compact structure can be achieved, and the invention is suitable for subsequent application and research on the fields of wireless communication, imaging, radar and the like.

Description

technical field [0001] The present invention relates to the field of terahertz radiation sources, and more specifically relates to an internal modulation terahertz source based on a waveguide structure and an internal modulation method thereof. Background technique [0002] The terahertz band refers to the electromagnetic spectrum range between microwave and infrared waves with a frequency of 0.1-10THz. It has the characteristics of large information carrying capacity (compared to microwave), high spatiotemporal coherence, and low photon energy. It presents a very broad application prospect in the fields of wireless communication, imaging, radar and national defense security. High-performance terahertz radiation sources and their effective modulation are the basis for many applications of terahertz technology, such as the modulation of terahertz waves in communication, radar and other signal processing and material control. At present, with the advancement of terahertz scie...

AI Technical Summary

Problems solved by technology

At present, with the advancement of terahertz science and technology, terahertz key technologies and their applications represented by terahertz radiation sources and terahertz functional devices (such as modulation devices) have made great progress, but they have also encountered development bottlenecks, such as The modulation method of terahertz waves is relatively complex and single, and terahertz radiation sources and functional devices cannot be effectively integrated. These bottlenecks greatly limit the application of terahertz technology in the fields of wireless communication, terahertz imaging and radar

[0003] Radiation sources such as return wave tubes and solid-state electronics based on electronic methods realize 225GHz terahertz radar and 300GHz terahertz communication by means of electrical modulation. Due to the limitation of electronic methods, their operating frequency is generally below 1THz. , due to the limitation of bandwidth, large-capacity information transmission cannot be realized

Quantum cascade lasers based on semiconductor quantum well technology can realize miniaturized continuous terahertz output, and realize 4.1THz and 2.9THz digital communication by using the modulation of pump current. This kind of radiation source can be effectively integrated with the modulator , truly realize the integrated and miniaturized terahertz application, but because the quantum cascade laser needs to work at a low temperature, this increases the complexity of the system

The terahertz source based on the nonlinear optical method has the advantages of low cost, simple structure, and room temperature operation, and is widely used in terahertz. Due to the low conversion efficiency and the lack of nonlinear materials in the terahertz band, the output Low power, terahertz modulation methods are mostly limited to external cavity modulation methods of terahertz radiation sources, such as liquid crystal and VO 2 Microstructured phase change materials, which use electricity, magnetism and light to affect the characteristics of materials to achieve terahertz wave modulation. These modulation methods are complex on the one hand, and low in modulation efficiency on the other hand. At the same time, they bring miniaturization and Integration creates difficulties

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