Petahertz-scale nonlinear photoconductive sampling in air

Photoconductive-Sampling Time-Interleaved CMOS ADC

High speed analog-to-digital converters capable of digitizing signals with bandwidths of several tens of GHz have applications in high-speed instrumentation, wideband radar and optical communications. However, the design of converters with such high input bandwidths is constrained by the need for wideband sample-and-hold circuits with sufficiently low clock jitter. A number of photonic sampling...

Ultrabroadband photoconductive detection: Comparison with free-space electro-optic sampling

The spectral response of a low-temperature-grown GaAs photoconductive ~PC! antenna is compared with that of the electro-optic sampling technique for the frequency region up to 40 THz. The spectral response of the PC antenna for broadband detection is found to be determined by the temporal profile of the number of photocarriers injected by ultrashort optical gate pulses. © 2001 American Institut...

Petahertz optical oscilloscope

The time-dependent field of an electromagnetic pulse can be measured if there is a fast enough gate. For terahertz radiation, femtosecond photoinjection of free carriers into a semiconductor in the presence of the terahertz radiation can serve as the gate1. For visible or infrared radiation, attosecond photoionization of a gas target in the presence of the optical field is a direct analogue2–8....

Radioactive Particulate Air Sampling

Adsorption efficiency of functionalized multi-walled carbon nanotube in sampling trichloroethylene in air

Introduction: Trichloroethylene (TCE) is an industrial solvent which is often used as a degreaser for metal parts. Due to adverse health effects and carcinogenic properties of this solvent, knowing its concentration in the workplace atmosphere is really crucial. Nowadays, carbon nanotubes with high efficiency are being used for sampling of this chemical. Method:</stron...