Experimental 6-GHz frozen wave generator with fiber-optic feed

A versatile high voltage nano- and sub-nanosecond pulse generator

“…This generator can now be used to investigate the effects of intense nanosecond and subnanosecond pulses on biological cells or tissues when combined to specific pulse delivery systems via coaxial cables [39][40][41][42]. However, one should be aware that depending on the pulse applicator (electroporation cuvettes, microchambers, microfluific biochips,…), the pulse across the biological load can be significantly different from the pulse measured across an ideal 50 Ω load, especially when the pulse duration decreases [33]. To maximize the energy transfer to the biological load with pulses of a few nanoseconds or less, we are currently developing and characterizing wideband pulse delivery systems with coaxial connectors [43].…”

“…The generator is built on the frozenwave generator concept [33]. A transmission line is used as a capacitive energy storage element of a primary high voltage DC power supply.…”

Frozen wave generation of bandwidth-tunable two-cycle THz radiation

“…In this paper we report on the application of an optoelectronic technique for the generation of tunable THz radiation. Our approach employs the concept of frozen wave generation [20][21][22][23][24] in the formation of ultrahighfrequency radiation. Operation of our device is independent of the semiconductor substrate carrier lifetime as long as the carrier lifetime, c , is longer than both the transit time of the waveform across the frozen wave generator (FWG) segments and the discharge time of the photoconductive switches.…”

“…Since optically activated FWG's offer low jitter and high switching efficiency, the potential exists for these devices to operate at even larger bandwidths. Thaxter and Bell 24 successfully demonstrated a two-and-one-half-cycle device that produced a 6-GHz pulse train. Interestingly, all the previously reported FWG devices have bandwidths in the MHz to GHz range, [20][21][22][23][24][25] are operated as singlefrequency generators, are cumbersome in size, and require a relatively high energy per pulse to close the photoconductive switches.…”

“…Thaxter and Bell 24 successfully demonstrated a two-and-one-half-cycle device that produced a 6-GHz pulse train. Interestingly, all the previously reported FWG devices have bandwidths in the MHz to GHz range, [20][21][22][23][24][25] are operated as singlefrequency generators, are cumbersome in size, and require a relatively high energy per pulse to close the photoconductive switches. In these devices, the maximum bandwidth is limited by two factors: the rise time of the switches and the inherent propagation delay between the sequential photoconductive switches that is due to cable interconnections.…”