Abstract: A spatial terahertz wave phase modulator based on the high electron mobility transistor is provided. The phase modulator combines the quick-response high electron mobility transistor with a novel metamaterial resonant structure, so as to rapidly modulate terahertz wave phases in a free space. The phase modulator includes a semiconductor substrate, an HEMT epitaxial layer, a periodical metamaterial resonant structure and a muff-coupling circuit. A concentration of 2-dimensional electron gas in the HEMT epitaxial layer is controlled through loading voltage signals, so as to change an electromagnetic resonation mode of the metamaterial resonant structure, thereby achieving phase modulation of terahertz waves. The phase modulator has a phase modulation depth of over 90 degrees within a large bandwidth, and a maximum phase modulation depth is about 140 degrees. Furthermore, the phase modulator is simple in structure, easy to machine, high in modulation speed, convenient to use, and easy to package.

Abstract: Terahertz external modulator based on high electron mobility transistors belongs to the field of electromagnetic functional devices technology. This invention includes the semiconductor substrate (1), the epitaxial layer (2), and the modulation-unit array (4). The epitaxial layer (2) is set on the semiconductor substrate (1). The modulation-unit (4), the positive electrode (3), and the negative electrode (5) are all set on the epitaxial layer (2). The modulation-unit array includes at least three units with each of them is composed of high electron mobility transistors and metamaterial-structure. The gates of transistors connect to the negative electrode (5), and the sources and drains connect to the positive electrode (3). This invention is used for manipulation of spatial transmission terahertz waves. It could be operated at room temperatures, normal pressures, and non-vacuum condition. It does not need to load on the waveguide, thus is easy to package and use.

Abstract: Terahertz external modulator based on high election mobility transistors belongs to the field of electromagnetic functional devices technology. This invention includes the semiconductor substrate (1), the epitaxial layer (2), and the modulation-unit array (4). The epitaxial layer (2) is set on the semiconductor substrate (1). The modulation-unit (4), the positive electrode (3), and the negative electrode (5) are all set on the epitaxial layer (2). The modulation-unit array includes at least three units with each of them is composed of high electron mobility transistors and metamaterial-structure. The gates of transistors connect to the negative electrode (5), and the sources and drains connect to the positive electrode (3). This invention is used for manipulation of spatial transmission terahertz waves. It could be operated at room temperatures, normal pressures, and non-vacuum condition. It does not need to load on the waveguide, thus is easy to package and use.