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Single phase and strained LuMnO(3) thin films are discovered to display coexisting ferromagnetic and antiferromagnetic orders. A large moment ferromagnetism (≈1μ(B)), which is absent in bulk samples, is shown to display a magnetic moment distribution that is peaked at the highly strained substrate-film interface. We further show that the strain-induced ferromagnetism and the antiferromagnetic order are coupled via an exchange field, therefore demonstrating strained rare-earth manganite thin films as promising candidate systems for new multifunctional devices.

We investigate the temperature-dependence of the light emission properties of Cu-dominated plasmas with pressures in the order of 1 bar and for currents between 0 and 2 kA. While the wavelength of Cu I 3d 9 4s5s transitions for currents above 1 kA is essentially constant, a 0.1 nm Stark blueshift is observed with decreasing current from 1 kA to zero. Using a lineshape analysis of the light emission spectra, which is based on solving a one-dimensional radiative transfer equation along the line-of-sight across the arc, we show that the transition wavelength increases linearly with temperatures in the 5000-10 000 K range. Based on this observation, we propose a simple method for the temperature diagnostic of plasmas that neither requires an absolute calibration of the intensity of the detected signal, nor complex simulation tools.

Plasma plume species from a ceramic La 0.4 Ca 0.6 MnO 3 target were studied by plasma mass spectrometry as a function of laser fluence, background gas, and deposition pressure to understand the interplay between plasma composition and oxide thin film growth by pulsed laser deposition. The plume composition reveals a significant contribution of up to 24% of negative ions, most notably using a N 2 O background. The significance of negative ions for thin film growth is shown for La 0.4 Ca 0.6 MnO 3 films grown in different background conditions where the best structural properties coincide with the largest amount of negative plasma species.One of the most versatile deposition techniques in solid state physics and analytical chemistry is the vaporization of condensed matter using photons. For oxide thin film growth, pulsed laser deposition (PLD) has evolved into a powerful deposition technique with a high control over crystalline properties. 1,2 Material removed from the target is directed towards a substrate where it re-condenses to form a film. The film's growth kinetics will depend on the material flux, plume composition, laser repetition rate, growth temperature, substrate, pressure, and background gas (vacuum, reactive). In addition, wavelength and fluence will determine if thermal or non-thermal evaporation processes are dominant as well as control the ratio between neutral and ionized species in a plume. 3 An important characteristic of PLD is the ability to realize, in principle, a stoichiometric transfer of ablated material from multi-elemental targets. This is an interesting fact, often taken for granted 2-5 but not necessarily correct in general. 6 However, the question is which plasma conditions have to be realized in order to grow a stoichiometric thin film with good properties, e.g., crystallinity. The ablation and deposition processes are connected by the transfer of material via the created plasma plume, and the thin film properties are closely related to the dynamics and composition of the respective plasma plume and growth properties on a substrate. To enhance the oxygen content in oxide thin films, a background gas is introduced, which also helps to moderate the kinetic energy (KE) of plume species. 1 Which plasma species are important for thin film growth? For sputtering, plasma species have been studied in detail, including the influence of negative ions. A densification of a film in the initial stages by ion bombardment has been linked to the presence of negative ions. 7 Likewise, negative ions are involved in an increase of the adatom's mobility which is a function of adatom to ion ratio. This is of particular importance for the kinetic energies of plasma species as low as 2-18 eV (Ref. 8) and typical when a background pressure is applied during film growth. The result is an increased nucleation density of up to 10 9 cm À2 . It is noteworthy to point out that negative oxygen ions are the more active oxidizing species compared to O þ as shown for silicon oxidation. 9 The example of the sputter p...

In this work, the reverse aluminum-induced layer exchange (R-ALILE) process with an initial layer stack of substrate/amorphous Si/Si-oxide/Al was studied in detail. The influence of the annealing temperature on the sample properties was investigated by optical reflection/transmission measurements and Raman spectroscopy. In addition, focused ion beam measurements were conducted to elucidate the inner structure of the layers. Two steps during crystallization were observed: at first a substrate/Al–Si composite/closed poly-Si layer structure is formed with an activation energy EApoly-Si=1.1 eV, which can be transferred to the stable configuration of substrate/Al+Si-islands (hillocks)/poly-Si by extended annealing or a high temperature step (EAhillocks=2.4 eV). Both processes are basically independent at low annealing temperatures due to the large difference in activation energy. The transformation of the Al–Si composite to the Al/Si-hillock structure involves the crystallization of a-Si regions and their subsequent coalescence, different to the feedback mechanism suggested for the normal ALILE process, where hillock and closed poly-Si growth are believed to influence each other. This insight into the process leads to the possibility to prepare poly-Si layers on pure Al back contacts by R-ALILE, possibly improving efficiencies of solar cells prepared by epitaxial overgrowth of poly-Si seed layers.

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We study the impact of Stark line shifts reported recently for Cu I transitions on the radiative cooling of Cu-dominated plasmas. The observed detuning in absorption between the hot core and cold shell of the arc leads to a reduction in radiation reabsorption compared to the case where Stark line shifts are neglected. Using a modeling based on a phenomenological treatment of the Stark line shift, we show that this reduction is below 2%.