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Title: Room temperature d 0 ferromagnetism in PbS films: nonuniform distribution of Pb vacancies
Because of the importance of ferromagnetism at room temperature, we search for new materials that can exhibit a non-vanishing magnetic moment at room temperature and at the same time can be used in spintronics. The experimental results indicate that d 0 ferromagnetism without any magnetic impurities takes place in PbS films made of close-packed lead sulfide nanoparticles of 30 nm. To explain the existence of the d 0 ferromagnetism, we propose a model where various PbS bulk and surface configurations of Pb-vacancies are analyzed. The bulk configurations have a zero magnetic moment while the two surface configurations with Pb vacancies with the same non-vanishing magnetic moments and lowest ground state energies contribute to the total magnetization. Based on the experimental value of the saturation magnetization, 0.2 emu g −1 , we have found that the calculated Pb vacancy concentration should be about 3.5%, which is close to typical experimental values. Besides being very important for applications, there is one feature of PbS d 0 ferromagnetism that makes this material special for fundamental research: PbS ferromagnetism can exhibit topologically driven spatial magnetic moment distributions ( e.g. , magnetic skyrmions) due to large spin–orbit coupling.  more » « less
Award ID(s):
1710512
PAR ID:
10099808
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Physical Chemistry Chemical Physics
Volume:
20
Issue:
47
ISSN:
1463-9076
Page Range / eLocation ID:
29804 to 29810
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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