Magnetic properties of diluted magnetic semiconductor Hg0.89Mn0.11Te

Abstract

The magnetization of Hg 0.89 Mn 0.11 Te single crystal grown by vertical Bridgman method was studied by using superconducting quantum interference device magnetometer (SQUID Magnetometer). First, magnetization measurements were done under various magnetic field strengths from -20 kOe to 20 kOe at 5 K, 15 K, and 77 K, respectively. Then, the magnetizations were measured with continuous changes of temperature in the range from 5 K to 300 K under the magnetic field of 0.1 kOe and 10 kOe, respectively. The modified Brillouin function was well fitted with the data of magnetization vs. magnetic field strength. The analysis indicated that there was an antiferromagnetic exchange coupling among Mn 2+ ions. The results of reciprocal susceptibility vs. temperature fit Curie-Weiss law very well at the temperatures above 40 K, but deviate from the law from 5 K to 40 K, which shows that the antiferromagnetic exchange coupling among Mn 2+ ions increases in the lower temperature range below 40 K. The experimental result was explained by extending higher-order terms in the calculation of susceptibility and fitted by a power law function. The measurements reveal that Hg 0.89 Mn 0.11 Te possesses paramagnetic properties at temperatures from 5 K to 300 K.

Magnetic Technologies and Green Solvents in Extraction and Separation of Bioactive Molecules Together with Biochemical Objects: Current Opportunities and Challenges

“…According to the current systematic study [29,30], the mechanism of magnetic fields on the separation process can be mainly elucidate as follows: (1) they can influence the charge distribution and network structure of water, and then the Lorentz force of a magnetic field on water molecules will be strengthened after the polarization of the latter, which can cause the secondary hydration layer in the structure of water being pushed off. As a result, water can be well dispersed in the single molecular state and the object particles (e.g., bioactive solutes and herbal materials) in the solution are easily separated from the water molecule binding to the precipitate; in addition, in terms of crystallization, magnetic treatment can reduce the critical radius of crystallization and form microcrystals easily.…”