Polycrystalline indium films in the percolation threshold regime: time correlation between electric conduction and optical properties with film morphology

Clark, N.J.; Vargas, William E.; Azofeifa, D. E.; Sáenz‐Arce, Giovanni; Solís, Hugo; Ramírez-Hidalgo, Gustavo

doi:10.1088/2053-1591/1/1/016302

Cited by 2 publications

(2 citation statements)

References 42 publications

(53 reference statements)

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“…The large particles are flattened which means that the polarization parallel to the plane of the substrate tends to be null, and they produce a shadow effect over the nano-sized ones. In the case of indium, it has been shown that the coexistence of close-packed submicron-sized particles, with nano-sized ones between them, forming thin films has significant effect in their optical properties [59], with a non negligible component of reflected diffuse radiation. The large particles in the L-film are dispersed which means that a small fraction of diffuse reflection should be expected.…”

Section: Dielectric Function Of a Thin Pd Film At Rtmentioning

confidence: 99%

Optical, charge transport and magnetic properties of palladium retrieved from photometric measurements: approaching the quantum mechanics background

et al. 2019

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A parametric Drude–Lorentz (DL) model is used to describe the spectral variation of the dielectric functions of bulk palladium samples at low and room temperature. In addition to the contribution of conduction electrons, the contribution of holes is also explicitly accounted for in the model. A simulated annealing method is applied to obtain the optimized values of the parameters involved in the model: volume plasma frequency of conduction electrons, high frequency dielectric constant, collision frequency of holes and corresponding relaxation time, and two additional parameters from which the effective mass of holes and collision frequency of conduction electrons are evaluated. Oscillatior strengths, resonance frequencies, and widths entering in the Lorentz contribution to the dielectric function are also optimized. Renormalization of the oscillator strengths requires the introduction of a new parameter in the context of the DL model: the ratio between number density of conduction electrons and number density of metal atoms, whose optimized value fits very well with its evaluation from band structure calculations and from independent measurements. Inclusion of this parameter in the framework allows us to evaluate additional quantities related to the charge-carrier transport: average effective masses, Fermi energies and electronic densities of states at the corresponding Fermi energies, intrinsic electrical resistivity, intrinsic mean free paths, heat capacities, mobilities, as well as paramagnetic and diamagnetic susceptibilities, for both electrons and holes. The optimized resonance frequencies are compared with energy differences between plausible interband transitions, in accordance with reported band structure diagrams and with our own band structure obtained from density functional theory calculations.

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Section: Dielectric Function Of a Thin Pd Film At Rtmentioning

confidence: 99%

Optical, charge transport and magnetic properties of palladium retrieved from photometric measurements: approaching the quantum mechanics background

et al. 2019

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“…A shutter near the QCM surface (see figure 1) allows us to immediately stop the interaction between the beam of atoms and the QCM. In order to avoid any environmental contamination, the system is mounted inside a high vacuum apparatus modified from that of [21] with the capacity to maintain pressures in the range of roughly 10 −7 Torr (10 −5 Pa). The pressure is constantly monitored by a pressure gauge model 354 MICRO-ION and kept stable in the order of 10 −7 Torr (10 −5 Pa) during all measurements reported below.…”

Section: Methodsmentioning

confidence: 99%

Energy exchange between atoms with a quartz crystal μ-balance

et al. 2018

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We propose an experimental method to fully characterize the energy exchange of particles during the physical vapor deposition (PVD) process of thin surface layers. Our approach is based on the careful observation of perturbations of the oscillation frequency of a quartz crystal μ-balance induced by the particles' interaction. With this technique it is possible to measure the momentum exchange of the atoms during the evaporation process and determine the ideal evaporation rate for uniform energy distribution. We are able to follow the desorption dynamics of particles' immediately after the first layers have been formed. These results are in close relation to the surface binding energy of the evaporated material and offer a better control to obtain the desired properties of the thin surface layer. The novelty of our work consists of the demonstration that quartz crystal μ-balance can be successfully implemented to monitor complex dynamics through the energy interaction of particles during PVD. We applied our technique to investigate the PVD mechanism for diverse elements, usually implemented in the development of film surface layers, such as Cu, W, Au, Gd and In, and confirm that our results are in agreement with measurements done previously with other techniques such as low temperature photo-luminescence.

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Polycrystalline indium films in the percolation threshold regime: time correlation between electric conduction and optical properties with film morphology

Abstract: Temperature-and hydrogen-induced changes in the optical properties of Pd capped V thin films D E Azofeifa, N Clark, W E Vargas et al.-Collective response of silver islands on a dielectric substrate W E Vargas, D E Azofeifa, N Clark et al.

Cited by 2 publications

References 42 publications

Optical, charge transport and magnetic properties of palladium retrieved from photometric measurements: approaching the quantum mechanics background

Optical, charge transport and magnetic properties of palladium retrieved from photometric measurements: approaching the quantum mechanics background

Energy exchange between atoms with a quartz crystal μ-balance

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