In:
Japanese Journal of Applied Physics, IOP Publishing, Vol. 50, No. 3R ( 2011-03-01), p. 035804-
Abstract:
A partially Fe-substituted solid solution of a higher manganese silicide, (Mn 1- x Fe x )Si γ , has been prepared by means of arc-melting and a subsequent annealing process. According to the linear relationship between x and lattice parameters, the solid solution can be prepared up to x = 0.35. The compounds consist of two tetragonal subsystems of [Mn 1- x Fe x ] and [Si] , with an irrational c -axis ratio γ= c Mn / c Si ∼1.7. With increasing x from 0 to 0.35, equivalent to increase electron carriers, the a -axis and c Mn -axis lengths gradually decrease, while the c Si -axis length linearly increases. On the basis of a valence electron counting rule, we expected that a transition from p-type to n-type would occur at x = 0.23 ±0.05. This transition is experimentally confirmed at x ∼0.28; the n-type samples are prepared at 0.28 ≤ x ≤0.35. The electrical conductivity at room temperature exhibits symmetrical curves versus x for both p- and n-type samples. However, the solubility limit of Fe appears to suppress any further increase in carrier concentration, resulting in poor electrical conductivity for n-type samples. As a consequence, the maximum dimensionless figure-of-merit Z T = 0.071 at 644 K is obtained for a sample with x = 0.30.
Type of Medium:
Online Resource
ISSN:
0021-4922
,
1347-4065
DOI:
10.1143/JJAP.50.035804
Language:
Unknown
Publisher:
IOP Publishing
Publication Date:
2011
detail.hit.zdb_id:
218223-3
detail.hit.zdb_id:
797294-5
detail.hit.zdb_id:
2006801-3
detail.hit.zdb_id:
797295-7
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