The diode heterostructures for ÒÍz devices

D. G. Pavelyev ¹, A. P.Vasilev², V. A. Kozlov ^1,3, Yu. I. Koschurinov ¹, E .S. Obolensky¹, S. V. Obolensky ¹, V. M. Ustinov ⁴

 ¹Lobachevsky State University of  Nizhni Novgorod
² SHM R&E Center, RAS, Saint Petersburg
³IPM RAS, Nizhni Novgorod
⁴Ioffe Institute, Saint Petersburg

The paper is received on on December 17, 2015, after correction - on December 28, 2015

 

Abstract. Short GaAs/AlAs superlattices with a small number of periods were investigated theoretically and experimentally. The possibility of effective application of the short superlattices in the frequency range of terahertz radiation was ascertained. In this paper, the band structures of the classical semiconductor superlattices with number of periods more than hundred, and the short superlattices with number of periods equal to 18 and 6, were considered. The current-voltage characteristics of the superlattices were calculated by Monte Carlo method. The high frequency properties of the diode structures with a small area (1-2 micron ²) of the active region of the superlattice were calculated. The transit time effects, the resistance of ohmic contacts and the resistance of transition layers were taking into account. The conditions (including number of periods) at which the upper frequency limit of such structureswas maximized were determined. It was found that the short superlattices exhibit significant advantages over the long ones. The effective application of the short superlattices for the frequency multiplier devices up to 8 THz and for the high frequency receivers (harmonic mixers) up to 5.3 THz were experimentally demonstrated for the first time

Key words: terahertz radiation, superlattice, miniband, ballistic electron transport, harmonic mixers.