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Ultrafast laser spectroscopy of antiferromagnets
Saidl, Vít ; Němec, Petr (advisor) ; Kužel, Petr (referee) ; Hamrle, Jaroslav (referee)
This work is dedicated to the study of two antiferromagnetic materials that are suitable for use in spintronic devices. In series of FeRh samples we studied the transition temperature between the antiferromagnetic and ferromagnetic phases. We developed a method based on material optical response for a quick determination of this temperature, which enabled us to study with a spatial resolution of 1 μm a magnetic inhomogeneity of prepared samples.We also developed a method for a determination of the Néel temperature and the magnetization easy axis position in thin films prepared from compensated antiferromagnetic metal. We successfully applied this method on an uniaxial sample of CuMnAs and we discussed its applicability for a research of samples with a biaxial magnetic anisotropy.
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Optical spectroscopy of magnetic semiconductors suitable for spintronic applications
Saidl, Vít ; Němec, Petr (advisor) ; Mics, Zoltán (referee)
In this work we investigate optical properties of new antiferromagnetic semiconductor - LiMnAs. This semiconductor oxidizes easily in air. This fact complicates significantly the investigation of its properties by the optical spectroscopy. This problem was solved by a construction of the optical setup that enables measurements of the reflectivity spectra directly in the chamber where this semiconductor is prepared by a molecular beam epitaxy (MBE). Firstly, the reliability of this optical setup was tested by the measurements of the reflectivity spectra of the well known semiconductors (GaAs and InAs). Secondly, the first measurements of LiMnAs reflectivity directly in the MBE chamber was performed.
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Investigation of magnetically-ordered materials by optical spectroscopy
Saidl, Vít
In this work we study thin epilayers of new antiferromagnetic semimetal CuMnAs by time-resolved magneto-optical experiments. In 10 nm layers of CuMnAs, we observed a harmonic dependence of the dynamical magneto-optical signal on the orientation of probe pulse linear polarization. This shows that in this 10 nm layer there is an in-plane uniaxial magnetic anisotropy which can be detected due to a quadratic magneto-optical effect - magnetic linear dichroism. From the measured data we also estimated the Néel temperature and the spectral variation of the magneto-optical coefficient describing the magnitude of the magnetic linear dichroism in this sample. Powered by TCPDF (www.tcpdf.org)
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Ultrafast laser spectroscopy of antiferromagnets
Saidl, Vít ; Němec, Petr (advisor) ; Kužel, Petr (referee) ; Hamrle, Jaroslav (referee)
This work is dedicated to the study of two antiferromagnetic materials that are suitable for use in spintronic devices. In series of FeRh samples we studied the transition temperature between the antiferromagnetic and ferromagnetic phases. We developed a method based on material optical response for a quick determination of this temperature, which enabled us to study with a spatial resolution of 1 μm a magnetic inhomogeneity of prepared samples.We also developed a method for a determination of the Néel temperature and the magnetization easy axis position in thin films prepared from compensated antiferromagnetic metal. We successfully applied this method on an uniaxial sample of CuMnAs and we discussed its applicability for a research of samples with a biaxial magnetic anisotropy.
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Investigation of magnetically-ordered materials by optical spectroscopy
Saidl, Vít
In this work we study thin epilayers of new antiferromagnetic semimetal CuMnAs by time-resolved magneto-optical experiments. In 10 nm layers of CuMnAs, we observed a harmonic dependence of the dynamical magneto-optical signal on the orientation of probe pulse linear polarization. This shows that in this 10 nm layer there is an in-plane uniaxial magnetic anisotropy which can be detected due to a quadratic magneto-optical effect - magnetic linear dichroism. From the measured data we also estimated the Néel temperature and the spectral variation of the magneto-optical coefficient describing the magnitude of the magnetic linear dichroism in this sample. Powered by TCPDF (www.tcpdf.org)
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Investigation of magnetically-ordered materials by optical spectroscopy
Saidl, Vít ; Němec, Petr (advisor) ; Veis, Martin (referee)
In this work we study thin epilayers of new antiferromagnetic semimetal CuMnAs by time- resolved magneto-optical experiments. In 10 nm layers of CuMnAs, we observed a harmonic dependence of the dynamical magneto-optical signal on the orientation of probe pulse linear polarization. This shows that in this 10 nm layer there is an in-plane uniaxial magnetic anisotropy which can be detected due to a quadratic magneto-optical effect - magnetic linear dichroism. From the measured data we also estimated the Néel temperature and the spectral variation of the magneto-optical coefficient describing the magnitude of the magnetic linear dichroism in this sample.
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Optical spectroscopy of magnetic semiconductors suitable for spintronic applications
Saidl, Vít ; Němec, Petr (advisor) ; Mics, Zoltán (referee)
In this work we investigate optical properties of new antiferromagnetic semiconductor - LiMnAs. This semiconductor oxidizes easily in air. This fact complicates significantly the investigation of its properties by the optical spectroscopy. This problem was solved by a construction of the optical setup that enables measurements of the reflectivity spectra directly in the chamber where this semiconductor is prepared by a molecular beam epitaxy (MBE). Firstly, the reliability of this optical setup was tested by the measurements of the reflectivity spectra of the well known semiconductors (GaAs and InAs). Secondly, the first measurements of LiMnAs reflectivity directly in the MBE chamber was performed.
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