We report the demonstration of a composite right/left-handed (CRLH) metamaterial waveguide for terahertz quantum-cascade (QC) lasers. By incorporating gap capacitors ( 250 nm) in the top metallization of a metal-metal waveguide operating in a higher order lateral mode, we have realized a CRLH transmission line that supports traveling modes with negative effective phase indices (i.e., left-hande...

The normal Doppler effect has well-established applications in many areas of science and technology. Recently, a few experimental demonstrations of the inverse Doppler effect have begun to appear in negative-index metamaterials. Here we report an experimental observation of the zero Doppler effect, that is, no frequency shift irrespective of the relative motion between the wave signal source an...

Athletes commonly attempt to enhance performance by training in normoxia but sleeping in hypoxia [live high and train low (LHTL)]. However, chronic hypoxia reduces muscle Na(+)-K(+)-ATPase content, whereas fatiguing contractions reduce Na(+)-K(+)-ATPase activity, which each may impair performance. We examined whether LHTL and intense exercise would decrease muscle Na(+)-K(+)-ATPase activity and...

This study investigated whether hypoxic exposure increased muscle buffer capacity (bm) and mechanical ef®ciency during exercise in male athletes. A control (CON, n ˆ 7) and a live high:train low group (LHTL, n ˆ 6) trained at near sea level (600 m), with the LHTL group sleeping for 23 nights in simulated moderate altitude (3000 m). Whole body oxygen consumption ( _ V O2) was measured under norm...

We study parametric amplification in nonlinear left-handed transmission lines, which serve as model systems for nonlinear negative-index metamaterials. We experimentally demonstrate the amplification of a weak signal in the three following regimes: with the signal in the left-handed band, with the signal in the stop band, and with the signal at a defect frequency. In particular, we demonstrate ...

Composite rightand left-handed (CRLH) transmission lines with regularly spaced Schottky varactors are characterized for propagation of short envelope pulses. Due to strong dispersion, a short pulse cannot travel on a conventional CRLH line without distortion. This distortion is compensated for by the effects of Schottky varactors such that the line supports solitonic pulses, whose pulse width d...

Lenses made of negative index materials have the ability to focus the propagating and evanescent components of electromagnetic waves. Such a possibility enables super resolution, in turn resulting in sharper, subwavelength size images. In this present work, we present subwavelength imaging that was obtained from a one-dimensional left-handed metamaterial (LHM) composed of alternating layers of ...

Metamaterials are an active area of interest currently due to their exotic electromagnetic properties not readily found in nature. In this report, the transmission line approach is used to design a Complementary Right Left Handed (CRLH) Transmisssion line. The characteristics of a modulated pulse propagation are studied. We look at how the variation of pulse width, centre frequency and pulse re...