CHMIELOWSKA , M.

CuO x-CeO 2-δ /Si thin films were elaborated by pulsed laser deposition. At the surface of all CuO x-CeO 2-δ thin films, Ce 4+ and Cu +1 ions were present. Depth profiles indicated that a Cu 2 O rich layer, roughly 40 nm thick, covered the CuO x-CeO 2−δ thin films. Apart from the copper enriched surface, the copper repartition in the thin films...

We report magnetotransport measurements performed on AlGaN/GaN devices with different buffer layers. Standard samples with a 1 μm thick GaN buffer show a linear Hall resistance and an almost constant magnetoresistance, as expected from a single two-dimensional electron gas (2DEG) at the AlGaN/GaN interface. Other samples, with an Al x Ga1– x N...

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We report measurements of the pulsed and dc current-voltage characteristics of AlGaN/GaN high-electron-mobility transistors as functions of geometry, temperature (from 300 down to 15 K), and operating conditions. An increase in the drain current with shortening of the pulse width from 1 µs to 400 ns is found to be significant at room...

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We report on room temperature electrically-induced terahertz emission from interdigitated GaN quantum well structures. The emission spectrum has been analysed in a Michelson interferometer using a 4K-Si bolometer as a terahertz detector. A resonant peak at the frequency of around 3 THz was observed in emission spectra. A threshold behaviour of...

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We report measurements of radiation transmission in the 0.220--0.325 THz frequency domain through GaN quantum wells grown on sapphire substrates at room and low temperatures. A significant enhancement of the transmitted beam intensity with the applied voltage on the devices under test is found. For a deeper understanding of the physical...

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We report on measurements of radiation transmission in the 0.220-0.325 THz and 0.75-1.1 THz frequency ranges through GaN quantum wells grown on sapphire substrates at nitrogen and room temperatures. Significant enhancement of the transmitted beam intensity with applied voltage is found at nitrogen temperature. This effect is explained by...

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