Terahertz radiation from CdxHg1−xTe photoexcited by femtosecond laser pulses

Abstract

Terahertz radiation from CdxHg1−xTe samples excited by femtosecond Ti:sapphire laser pulses were measured by using an ultrafast photoconductive antenna manufactured from low-temperature grown GaAs. Terahertz fields radiated by the samples of all three investigated alloy compositions with x=0, 0.2, and 0.3 were of the same order of magnitude. No azimuthal angle dependence of the radiated signal was detected, which evidences that linear current surge effect is dominating over nonlinear optical rectification.

Terahertz Emission from the Surfaces of InAs and Other Narrow-Gap Semiconductors

“…However, this is not observed experimentally at room temperature [5]; surely highly nonparabolic Γ valley is the main reason of the low THz emission from Cd 0.2 Hg 0.8 Te. After lowering the temperature to 80 K, the THz pulse power emitted from Cd 0.2 Hg 0.8 Te increases by approximately two orders of magnitude (Fig.…”

THz emission from semiconductor surfaces

“…No azimuthal angle dependence of the radiated signal was detected, indicating that bulk OR contribution is negligible in these cases. Terahertz fields radiated by the samples of all three investigated Cd x Hg 1−x Te alloy compositions (x = 0, 0.2, and 0.3) were of the same order of magnitude and no clear dependence on x was found [28]. This experimental result was explained by the electron transitions from the spin-orbital split valence band to the conduction band.…”

Perovskite oxide nanotubes: synthesis, structural characterization, properties and applications

“…Not surprisingly, analogous measurements for the BFO nanotubes generated from 100 nm diameter pores could not be properly obtained due to the roughness of the tube surface [Fig. 11(a HRTEM lattice images further confirm the crystalline nature and composition of the as-prepared nanotubes, and a typical crystalline domain with an interplanar spacing of $0.282 nm, corresponding to the (110) ring in the SAED spectrum, is shown in Fig. 11(d).…”