| 1. |
- Gryglas-Borysiewicz, M., et al.
(författare)
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Hydrostatic pressure study of the paramagnetic-ferromagnetic phase transition in (Ga,Mn)As
- 2010
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Ingår i: Physical Review B (Condensed Matter and Materials Physics). - 1098-0121. ; 82:15
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Tidskriftsartikel (refereegranskat)abstract
- The effect of hydrostatic pressure on the paramagnetic-ferromagnetic phase transition has been studied in (Ga,Mn)As. The variation in the Curie temperature (T-C) with pressure was monitored by two transport methods: (1) measurement of zero-field resistivity versus temperature rho(T) and (2) dependence on temperature of the Hall voltage hysteresis loop. Two specimens of different resistivity characteristics were examined. The measured pressure-induced changes in T-C were relatively small (on the order of 1 K/GPa) for both samples, however they were opposite for the two.
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| 2. |
- Kaczmarski, J., et al.
(författare)
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Controlling In-Ga-Zn-O thin films transport properties through density changes
- 2016
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Ingår i: Thin Solid Films. - : Elsevier BV. - 0040-6090. ; 608, s. 57-61
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Tidskriftsartikel (refereegranskat)abstract
- In the following study we investigate the effect of the magnetron cathode current (I-c) during reactive sputtering of In-Ga-Zn-O (a-IGZO) on thin-films nanostructure and transport properties. All fabricated films are amorphous, according to X-ray diffraction measurements. However, High Resolution Transmission Electron Microscopy revealed the a-IGZO fabricated at I-C = 70 mA to contain randomly-oriented nanocrystals dispersed in amorphous matrix, which disappear in films deposited at higher cathode current. These nanocrystals have the same composition as the amorphous matrix. One can observe that, while I-C is increased from 70 to 150 mA, the carrier mobility improves from mu(Hall) = 6.9 cm(2)/Vs to mu(Hall) = 9.1 cm(2)/Vs. Additionally, the increase of I-C caused a reduction of the depletion region trap states density of the Ru-Si-O/In-Ga-Zn-O Schottky barrier. This enhancement in transport properties is attributed to the greater overlapping of s-orbitals of the film-forming cations caused by increased density, evidenced by X-ray reflectivity, at a fixed chemical composition, regardless nanostructure of thin films. (C) 2016 Elsevier B.V. All rights reserved.
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| 3. |
- Kaczmarski, J., et al.
(författare)
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Transparent Ru–Si–O/In–Ga–Zn–O MESFETs on flexible polymer substrates
- 2018
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Ingår i: IEEE Transactions on Electron Devices. - 1557-9646 .- 0018-9383. ; 65:1, s. 129-135
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Tidskriftsartikel (refereegranskat)abstract
- With the development of novel device applications, e.g., in the field of Internet of Things or point-of-care personalized diagnostic systems, came an increased demand for MESFETs for fast and low-power consumption integrated circuits and active-matrix displays. In this paper, we present fabrication and characterization of transparent Ru–Si–O/In–Ga–Zn–O MESFETs on flexible substrates. The use of transparent conducting oxide, namely, Ru–Si–O, as Schottky gate electrode, allows for processing the devices at room temperature, enabling the utilization of such low-temperature substrates as polyethylene terephthalate foil and paper. It was shown that tuning the device geometry allows realization of transistors providing on-current up to 2 mA, while the highest on-to-off current ratio equals 2 × 105, with off-current below 1 nA, carrier mobility in the channel exceeds 9 cm2·V−1·s−1, and subthreshold swing is below 250 mV·decade−1
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| 4. |
- Juszynski, P., et al.
(författare)
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Influence of Epitaxial Strain on Magnetic Anisotropy in (Ga,Mn)As
- 2012
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Ingår i: Acta Physica Polonica. Series A: General Physics, Physics of Condensed Matter, Optics and Quantum Electronics, Atomic and Molecular Physics, Applied Physics. - 0587-4246. ; 122:6, s. 1004-1006
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Tidskriftsartikel (refereegranskat)abstract
- Two (Ga,Mn)As samples having different magnetic anisotropy (one with in-plane easy axis and another one with out-of-plane easy axis) were studied by means of magnetotransport experiments. Anisotropy field B-A was determined for both samples as a function of temperature. For the sample having in-plane easy axis, an inversion of the direction of planar Hall effect hysteresis was observed upon increase of temperature. This result was simulated using the Stoner-Wohlfarth model.
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