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Diego F. Coral

Publications and source records attributed to Diego F. Coral.

2 recordsLinked to original sources

Spin transport analysis for a spin pseudovalve-type L_l/SC/L_r trilayer for L = {FeCr, Fe, Co, NiFe, Ni} and SC = {GaSb, InSb, InAs, GaAs, ZnSe}

In this work, we present a theoretical study of spin transport in a trilayer pseudospin-valve (PSV) heterostructure composed of electrode (L_l)/insulator/electrode (L_r). The insulating layer corrresponds to a semiconductor (SC) with a zinc-blende crystal structure from the III-V (GaSb, InSb, InAs, and GaAs) or the II-VI (ZnSe), while the electrodes are ferromagnetic materials L_j = {FeCr, Fe, Co, NiFe, Ni}. This combination yields 125 possible PSV configurations. The theoretical model implemented is based on the approach proposed by J. C. Slonczewski. In our approach, the exchange splitting in the ferromagnetic materials and the spin-orbit coupling (SOC) of the Dresselhaus and Rashba types in the semiconductors are included, allowing control of the wave vector associated with the spin states. The tunnel magnetoresistance (TMR) is calculated at low temperature as a function of the semiconductor thickness, parameterized with respect to the crystallographic axis that favors the magnetization direction in the ferromagnetic electrodes, within the Landauer--Büttiker formalism in the single-channel regime. The results show that the TMR reaches its maximum value independently of the relative orientation between the magnetization vector and the crystallographic direction. The most efficient configuration corresponds to Fe_{90}Cr_{10}/GaSb/Fe_{90}Cr_{10}, with a TMR value of 83.60%. Furthermore, the Dresselhaus SOC contributes more significantly to the TMR than the Rashba SOC. Finally, the TMR varies when the electrodes L_j are permuted, due to differences in their Fermi energies. The obtained results are compared with previous studies reported in the literature based on alternative theoretical frameworks or assumptions, showing good agreement.

cond-mat.mes-hall↗

Designing a portable radiofrequency source for magnetic hyperthermia applications

In the 21st century, new and alternative non-radioactive methods for cancer treatment have been developed. One of this is magnetic hyperthermia (MH), which is based on the ability of magnetic nanoparticles (MNP) to transduce electromagnetic energy into heat. If MNP are inside cancer cells, heat induces cells death. The success of HM as cancer therapy depends on two factors, first, the NPM properties and second, the frequency and amplitude of the radio frequency (RF) applied field. Therefore, in this work a design of a portable radio frequency source for magnetic hyperthermia experiments is presented. The design consists of two parts, the first part corresponds to the RF source composed by a RLC parallel circuit, the capacity and inductance values have been chosen in order to achieve the RF range of frequency, and the second part corresponds to the design of a magnetization sensor circuit. While the first circuit produces the RF field, the second circuit serves as a detector of the NPM induced magnetization. The development of this radiofrequency source makes it possible to determine the applicability of an NPM system in the treatment of cancer by magnetic hyperthermia, opening doors for future research focused on the application of nanotechnology in biomedicine.

physics.med-ph↗