Phenomenom of The Magnetic Instabiliti in Some Magnets with Collectivized Electrons

Öz

     An effective method of studying the properties of zonal magnets is to affect the magnet by the - exchange field. The investigation of the impact of an - exchange field on the behavior of zonal metamagnetic  was the objectives of this work. Gadolinium was used as a magnetizing element to exclude the effect of a crystal field. Therefore, in this work, the magnetic properties of the system  were studied. The measurement results showed that, as  is substituted for , the field  decreases monotonically. The magnetization of the -subsystem exceeds that of the -subsystem , then the magnetic moment of the -subsystem is oriented parallel to the external field, while the moment of the -subsystem is antiparallel to the latter, here the  exchange interaction leads to a decrease in the metamagnetic transition field. The exchange field  helps the external field with magnetization. When , the magnetization of the -subsystem is oriented along the field. The external field does not magnetize the -subsystem, but demagnetizes it, and then to be magnetized parallel to this field. When these compounds become magnetically ordered, the magnetization degrees of - и -subsystems equalize in the concentration zone. The dependence of the magnetic moment of the compositions of the -subsystem on the content of gadoliniums increases linearly with the increasing content of gadolinium, which is due to the increasing effective field affecting the -subsystem. The data for the systems with different content of aluminum within an error are on the line.

Anahtar Kelimeler

• Instability,Metamagnetizm,Magnetization,Exchange Interaction,Critical Field

Abstract

An effective method of studying the properties of zonal magnets is to affect the magnet by the 𝑓-𝑑 exchange field. The investigation of the impact of an 𝑓-𝑑 exchange field on the behavior of zonal metamagnetic 𝑌𝐶𝑜2 was the objectives of this work. Gadolinium was used as a magnetizing element to exclude the effect of a crystal field. Therefore, in this work, the magnetic properties of the system 𝑌1−𝑡𝐺𝑑𝑡(𝐶𝑜1−𝑥𝐴ℓ𝑥)2 were studied. The measurement results showed that, as 𝑌 is substituted for 𝐺𝑑, the field 𝐻𝑚 decreases monotonically. The magnetization of the 𝑑-subsystem exceeds that of the 𝑓-subsystem (𝑀𝑑>𝑡𝑀𝑓), then the magnetic moment of the 𝑑-subsystem is oriented parallel to the external field, while the moment of the 𝑓-subsystem is antiparallel to the latter, here the 𝑓−𝑑 exchange interaction leads to a decrease in the metamagnetic transition field. The exchange field 𝐻𝑓−𝑑 helps the external field with magnetization. When 𝑀𝑑<𝑡𝑀𝑓, the magnetization of the 𝑓-subsystem is oriented along the field. The external field does not magnetize the 𝑑-subsystem, but demagnetizes it, and then to be magnetized parallel to this field. When these compounds become magnetically ordered, the magnetization degrees of 𝑓- и 𝑑-subsystems equalize in the concentration zone. The dependence of the magnetic moment of the compositions of the 𝑑-subsystem on the content of gadoliniums increases linearly with the increasing content of gadolinium, which is due to the increasing effective field affecting the 𝑑-subsystem. The data for the systems with different content of aluminum within an error are on the line.

Kaynakça

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