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Research
My research is to understand
fundamental properties of complex materials using advanced numerical techniques
such as density-functional theory, Monte-Carlo simulation, and (quantum
mechanical) molecular dynamics. I am currently working with Prof. Chris Van de Walle
at the University of California-Santa Barbara (UCSB). My Ph.D. studies were
with Prof. S. D. Mahanti at
Michigan State University (MSU).
Current/recent research projects: (1) Hydrogen storage materials.
(2) Monte Carlo simulation of charge
ordering in a fcc
Coulomb lattice gas. (3) Ab initio
studies of atomic and electronic structures of ternary and quaternary
narrow band-gap semiconductors (with focus on thermoelectric applications).
(4) Theory of defects in narrow band-gap semiconductors (bulk, films, and
nanoclusters). (5) Clustering and nanostructure formation in bulk
thermoelectric materials.
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Partial charge density
associated with (a) hyper-deep and (b) deep defect states created by an
In substitutional impurity in PbTe. These are bonding and anti-bonding
states of In s and Te p orbitals.
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Highlights
(from our recent publications)
Partial charge density
associated with defect states created by Te vacancies in PbTe thin films;
see PRB 76, 115432 (2007).
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Partial charge density associated with
defect states created by (a) Pb and (b) Te vacancies in PbTe; see PRB 76, 115432 (2007).
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Publications
1. K. Hoang and S. D. Mahanti, “Atomic
and electronic structures of thallium-based III-V-VI2 ternary
chalcogenides: Ab initio
calculations,” Physical
Review B 77, 205107 (2008).
2. L.-H. Ye, K. Hoang, A. J.
Freeman, S. D. Mahanti, J. He, T. M. Tritt, and M. G. Kanatzidis, “First
principles study of the electronic, optical and lattice vibrational
properties of AgSbTe2,” Physical Review B 77, 245203 (2008).
3. K. Hoang and S. D. Mahanti,
“Electronic structure of Ga, In, and Tl doped
PbTe: A detailed study of the impurity bands,” Physical Review B (under review).
4. M.-K. Han, K. Hoang, H. Kong, P.
Pcionek, C. Uher, K. M. Paraskevopoulos, S. D. Mahanti, and M. G.
Kanatzidis, “Substitution of Bi for Sb and its role in the thermoelectric
properties and nanostructuring in Ag1-xPb18MTe20
(M=Bi, Sb),” Chemistry of Materials 20, 3512 (2008).
5. K. Hoang, S. D. Mahanti, J. R.
Salvador, and M. G. Kanatzidis, “Atomic
ordering and gap formation in Ag-Sb-based ternary chalcogenides,” Physical Review
Letters 99, 156403 (2007).
PDF
See also: L.-H. Ye et al. (sx-LDA
calculations), Jovovic and Heremans
(Fermi surface measurements), Barabash et al. (first-principles cluster expansion)
6. K. Hoang, S. D. Mahanti, and P.
Jena, “Theoretical study of
deep-defect states in bulk PbTe and in thin films,” Physical Review
B 76, 115432 (2007).
PDF
7. S. D. Mahanti, K. Hoang, and S.
Ahmad, “Deep defect states in narrow band-gap semiconductors,” Physica B 401-402C, 291 (2007). PDF
8. J. R. Salvador, K. Hoang, S. D.
Mahanti, and M. G. Kanatzidis, “REAu2In4
(RE = La, Ce, Pr, and Nd): Polyindides from liquid Indium,” Inorganic Chemistry 46, 6933 (2007). PDF
9. S. Ahmad, S. D. Mahanti, K. Hoang,
and M. G. Kanatzidis, “Ab initio studies of the electronic structure of defects in PbTe,” Physical Review
B 74, 155205 (2006). PDF
10. S. Ahmad, K. Hoang, and S. D.
Mahanti, “Ab initio study
of deep defect states in narrow band-gap semiconductors: Group III
impurities in PbTe,” Physical Review Letters 96,
056403 (2006). PDF
11. K. Hoang, K. Desai, and S. D.
Mahanti, “Charge ordering and
self-assembled nanostructures in a fcc Coulomb
lattice gas,” Physical Review B 72,
064102 (2005); selected for the Virtual Journal
of Nanoscale Science and Technology 12 (August
15, 2005). PDF
Conference Proceedings
1. S. D. Mahanti, K. Hoang, and S.
Ahmad, “Atomic ordering, electronic structure, and transport properties of
LAST-m systems,” in Thermoelectric Power Generation, edited by T.P.
Hogan, J. Yang, R. Funahashi, and T. Tritt (Mater. Res. Soc. Symp. Proc. 1044,
Warrendale, PA, 2007), 1044-U04-06 (invited).
2. K. Hoang and S. D. Mahanti, “Defect
clustering and nanostructure formation in PbTe-based bulk thermoelectrics,”
in Thermoelectric Power Generation, edited by T.P. Hogan, J. Yang,
R. Funahashi, and T. Tritt (Mater. Res. Soc. Symp. Proc. 1044, Warrendale, PA,
2007), 1044-U02-08.
3. K. Hoang, S. D.
Mahanti, J. Androulakis, and M. G. Kanatzidis, “Electronic structure of AgPbmSbTem+2
compounds – Implications on thermoelectric properties,” in Materials and Technologies
for Direct Thermal-to-Electric Energy Conversion,
edited by J. Yang, T.P. Hogan, R. Runahashi, and G.S. Nolas (Mater. Res.
Soc. Symp. Proc. 886, Warrendale,
PA, 2006), 0886-F05-06.
4. H. Khang, S. D. Mahanti, B. K.
Rao, and P. Jena, “Magnetic and
thermal properties of interacting (MnxN) clusters,” in Clusters and
Nano-Assemblies: Physical and Biological Systems,
edited by P. Jena, S. N. Khanna, and B. K. Rao, World Scientific,
Singapore, 2005), p. 231.
Others
Ph.D. Thesis: “Atomic
and electronic structures of novel ternary and quaternary narrow band-gap
semiconductors” (200 pages [sorry, couldn’t make it shorter!]; may
be available online in the future). ABSTRACT
B.Sc. Thesis [in Vietnamese]: “Độ
tái chuẩn hóa khe dải trong giếng lượng tử
trong gần đúng lưỡng cực plasmon”
(Double plasmon-pole approximation for semiconductor quantum wells at
finite temperatures). PDF
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