[1] [1] Dhillon, S., Vitiello, M., Linfield, E., Davies, A., Hoffmann, M.C., Booske, J., Paoloni, C., Gensch, M., Weightman, P., Williams, G.P.: The 2017 terahertz science and technology roadmap. J. Phys. D Appl. Phys. 50(4), 043001 (2017)

[2] [2] Polese, M., Jornet, J.M., Melodia, T., Zorzi, M.: Toward end-to-end, full-stack 6G terahertz networks. IEEE Commun. Mag. 58(11), 48–54 (2020)

[3] [3] Siegel, P.H.: Terahertz technology. IEEE Trans. Microw. Theory Tech. 50(3), 910–928 (2002)

[4] [4] Dyakonov, M., Shur, M.: Shallow water analogy for a ballistic field effect transistor: new mechanism of plasma wave generation by DC current. Phys. Rev. Lett. 71(15), 2465 (1993)

[5] [5] Shur, M.S., Ryzhii, V.: Plasma wave electronics. Int. J. High Speed Electron. Syst. 13(2), 575–600 (2003)

[6] [6] Bhardwaj, S., Nahar, N.K., Rajan, S., Volakis, J.L.: Numerical analysis of terahertz emissions from an ungated HEMT using full-wave hydrodynamic model. IEEE Trans. Electron Dev. 63(3), 990–996 (2016)

[7] [7] El Fatimy, A., Dyakonova, N., Meziani, Y., Otsuji, T., Knap, W., Vandenbrouk, S., Madjour, K., Theron, D., Gaquire, C., Poisson, M.A.P.: AlGaN/GaN high electron mobility transistors as a voltage-tunable room temperature terahertz sources. J. Appl. Phys. 107(2), 024504 (2010)

[8] [8] Jaktas, V., Grigelionis, I., Janonis, V., Valuis, G., Kaalynas, I., Seniutinas, G., Juodkazis, S., Prystawko, P., Leszczyski, M.: Electrically driven terahertz radiation of 2DEG plasmons in AlGaN/GaN structures at 110 K temperature. Appl. Phys. Lett. 110(20), 202101 (2017)

[9] [9] Onishi, T., Tanigawa, T., Takigawa, S.: High power terahertz emission from a single gate AlGaN/GaN field effect transistor with periodic Ohmic contacts for plasmon coupling. Appl. Phys. Lett. 97(9), 092117 (2010)

[10] [10] Shalygin, V., Moldavskaya, M., Vinnichenko, M.Y., Maremyanin, K., Artemyev, A., Panevin, V.Y., Vorobjev, L., Firsov, D., Korotyeyev, V., Sakharov, A.: Selective terahertz emission due to electrically excited 2D plasmons in AlGaN/GaN heterostructure. J. Appl. Phys. 126(18), 183104 (2019)

[11] [11] Dasgupta, S., Nidhi, N., Brown, D.F., Wu, F., Keller, S., Speck, J.S., Mishra, U.K.: Ultralow nonalloyed ohmic contact resistance to self aligned N-polar GaN high electron mobility transistors by In (Ga) N regrowth. Appl. Phys. Lett. 96(14), 143504(2010)

[12] [12] Park, P.S., Rajan, S.: Simulation of short-channel effects in N-and Ga-polar AlGaN/GaN HEMTs. IEEE Trans. Electron Dev. 58(3), 704–708 (2011)

[13] [13] Denninghoff, D.J., Dasgupta, S., Lu, J., Keller, S., Mishra, U.K.: Design of high-aspect-ratio T-gates on N-polar GaN/AlGaN MIS-HEMTs for high fmax. IEEE Electron Device Lett. 33(6), 785–787 (2012)

[14] [14] Guo, H., Zhang, P., Yang, S., Wang, S., Gong, Y.B.: Numerical study on THz radiation of two-dimensional plasmon resonance of GaN HEMT array. Chin. Phys. B 32(4), 040701 (2023)

[15] [15] Nafari, M., Aizin, G.R., Jornet, J.M.: Plasmonic HEMT terahertz transmitter based on the Dyakonov-Shur instability: performance analysis and impact of nonideal boundaries. Phys. Rev. Appl. 10(6), 064025 (2018)

[16] [16] Crabb, J., Roman, X.C., Jornet, J., Aizin, G.R.: Plasma instability in graphene field-effect transistors with a shifted gate. Appl. Phys. Lett. 121(14), 3502 (2022)

[17] [17] Crabb, J., Cantos-Roman, X., Jornet, J.M., Aizin, G.R.: Hydro-dynamic theory of the Dyakonov-Shur instability in graphene transistors. Phys. Rev. B 104(15), 155440 (2021)

[18] [18] Lu, J., Denninghoff, D., Yeluri, R., Lal, S., Gupta, G., Laurent, M., Keller, S.P., DenBaars, S.K., Mishra, U.: Very high channel conductivity in ultra-thin channel N-polar GaN/(AlN, InAlN, AlGaN) high electron mobility heterojunctions grown by metalorganic chemical vapor deposition. Appl. Phys. Lett. 102(23), 232104 (2013)

[19] [19] Huang, Y., Yu, Y., Qin, H., Sun, J., Zhang, Z., Li, X., Huang, J., Cai, Y.: Plasmonic terahertz modulator based on a grating-coupled two-dimensional electron system. Appl. Phys. Lett. 109(20), 201110 (2016)

[20] [20] Guo, H., Yang, S., Zhang, P., Xing, R., Yu, G., Wang, S., Gong, Y.B.: Acoustic and optical plasmons excitation in double-channel AlGaN/GaN HEMT under asymmetric boundaries. AIP Adv. 14(4), 045224 (2024)

[21] [21] Guo, B., Yu, G., Zhang, L., Zhou, J., Wang, Z., Xing, R., Yang, A., Li, Y., Liu, B., Zeng, X.H.: High-performance N-polar GaN/AlGaN metal–insulator–semiconductor high-electron-mobility transistors with low surface roughness enabled by chemical–mechanical-polishing-incorporated layer transfer technology. Crystals (Basel) 14(3), 253 (2024)

[22] [22] Dyakonov, M., Shur, M.: Detection, mixing, and frequency multiplication of terahertz radiation by two-dimensional electronic fluid. IEEE Trans. Electron Dev. 43(3), 380–387 (1996)

[23] [23] Dyakonov, M., Shur, M.S.: Current instability and plasma waves generation in ungated two-dimensional electron layers. Appl. Phys. Lett. 87(11), 111501 (2005)

[24] [24] Otsuji, T., Hanabe, M., Nishimura, T.: A grating-bicoupled plasma-wave photomixer with resonant-cavity enhanced structure. Opt. Express 14(11), 4815–4825 (2006)

[25] [25] Popov, V., Polischuk, O., Shur, M.S.: Resonant excitation of plasma oscillations in a partially gated two-dimensional electron layer. J. Appl. Phys. 98(3), 033510 (2005)