GaAs devices and circuits for terahertz applications

Monte Carlo simulation of high‐order harmonics generation in bulk semiconductors and submicron structures

“…The hysteresis-like behavior of < I(U ) > (see Fig. 2 (b)) is accompanied by a rapid increase with f of the amplitude of both the fundamental and the higher order harmonics, what is typical for the strong C-U nonlinearity of varactor type [12]. This is illustrated by Fig.…”

“…Here the < I(U ) > diagram follows practically the static I-U relation. At f > 0.1 T Hz, the instantaneous < I(U ) > characteristic begins to differ significantly from that of the static case, what is typical for the strong capacitance-voltage C-U nonlinearity of varactor type [12].…”

“…Starting from an available source of fundamental signal in the frequency range f = 100 − 300 GHz [1], to achieve generation in the THz region one needs: (i) either to perform a multicascade multiplication by using frequency doubling and tripling [1], (ii) or to extract the 5th, or higher order harmonic, of the fundamental signal. For this sake, wide use is made of the nonlinearity of hot-carrier velocity-field (v-E) relation in bulk semiconductors [2][3][4][5][6][7][8], or of the nonlinearities of current-voltage (I-U) and capacitance-voltage (C-U) characteristics in Schottky-barrier structures [1,[9][10][11][12]. These nonlinearities are strongly dependent on the value of the excitation frequency.…”

Numerical modeling of TeraHertz electronic devices

“…Due to their strongly nonlinear current-voltage (I-V) and capacitance-voltage (C-V) characteristics, GaAs Schottkybarrier diodes (SBDs) are widely used in modern solid-state electronics as frequency multipliers in the subterahertz region [16][17][18] and mixers in the superterahertz region [18][19][20]. As a consequence, the intensity of fundamental and higher order harmonics of the current response, the intrinsic noise, and the signal-to-noise ratio of these devices are relevant parameters when assessing their electrical performances under high-frequency large-signal operation.…”

Theoretical Investigation of Large-Signal Noise in Nanometric Schottky-Barrier Diodes Operating in External Resonant Circuits

“…One of the most promising directions to develop solid-state sources of THz radiation working at room temperature is a frequency multiplication in GaAs Schottky-barrier diodes (SBDs) [1]. To extract the high-frequency signal, the SBD is usually loaded by a given external resonant circuit, which, due to feedback, can modify considerably the intrinsic noise spectrum of the unloaded SBD [2].…”