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Riga Event Timers have the ability to measure the interval between events with high resolution, on the order of picoseconds. However, they have several drawbacks, such as sensitivity to environmental temperature changes and an inability to capture the amplitude of the events. In this work, we present the ETAM: a next generation Event Timer. Its innovative features include adaptive correction of measurement errors based on an internal temperature sensor, and integrated peak-detector circuit to determine the amplitude of nanosecond-duration pulses. Evaluation shows that the ETAM has high thermal stability with a root mean square error (RMSE) of <3 ps in a temperature range between 0 and +40 °C, and accurate event amplitude measurement capability, with <2.3 mV RMSE in the 100–1000 mV range. These improvements allow the ETAM to be used in satellite laser ranging, optical time-domain reflectometry, and other field applications that require temperature- and amplitude-based time correction in addition to high robustness, performance, and stability. [ABSTRACT FROM AUTHOR]

The amplitude analysis of scanning electron microscope (SEM) signals is described, which reveals the emission properties of the studied rectangular relief structures. SEM signals are obtained at parallel and inclined positions of the SEM-probe axis relative to the walls of rectangular grooves in silicon. The physical meanings of the parameters of the SEM signals obtained in the recording mode of slow secondary electrons with parallel and inclined positions of the probe are determined. The existence of two mechanisms of secondary-electron emission is shown. Methods for separating the contributions of these mechanisms during the inclined scanning of straight-angle grooves are given. [ABSTRACT FROM AUTHOR]

An optical dispersion analysis and measurement technique based on frequency derivatives of the Jones matrix is presented. This approach enables measurement of all scalar and polarization-dependent phase and amplitude dispersion effects over a broad wavelength range in a single sweep. Owing to its differential nature, it can be more accurate than techniques that calculate dispersion by comparing phase and amplitude measurements from adjacent wavelengths in a sweep. The method involves measuring eight elementary parameters related to the frequency derivative of the Jones matrix. An experimental setup and data analysis methods for measuring the elementary parameters are presented. Three optical devices exhibiting various dispersive effects are tested, and the ability to measure all the elementary parameters is demonstrated. Elementary parameter estimation error is 1-2 ps in this proof-of-concept experiment. [ABSTRACT FROM PUBLISHER]

Using a doubly periodicity structure the extraordinary transmission of subwavelength metallic hole arrays in the microwave range can be boosted. Stacking several of such plates a left-handed metamaterial can be obtained as it is shown by the computed dispersion diagrams as well as the amplitude and phase measurements. An effective refraction index along the propagation direction can be calculated, giving a negative magnitude between -1 and 0. This enhances the emission by a focused beam with narrow beamwidth. Several practical applications like novel antennas are envisaged. [ABSTRACT FROM PUBLISHER]