RT Journal Article
T1 Tuning the spin transition and carrier type in rare-earth cobaltates via compositional complexity
A1 Zhang, Alan
A1 Oh, Sangheon
A1 Choi, Byoung Ki
A1 Rotenberg, Eli
A1 Brown, Timothy D.
A1 Spataru, Catalin D
A1 Kinigstein, Eli
A1 Guo, Jinghua
A1 Sugar, Joshua D.
A1 Salagre, Elena
A1 Mascaraque Susunaga, Arantzazu
A1 Michel, Enrique G.
A1 Shad, Alison C
A1 Zhu, Jacklyn
A1 Suhas Kumar1, 
A1 Witman, Matthew D.
A1 Kumar, Suhas
A1 Talin, A. Alec
A1 Fuller, Elliot J.
AB There is growing interest in material candidates with properties that can be engineered beyond traditional design limits. Compositionally complex oxides (CCO), often called high entropy oxides, are excellent candidates, wherein a lattice site shares more than four cations, forming single-phase solid solutions with unique properties. However, the nature of compositional complexity in dictating properties remains unclear, with characteristics that are difficult to calculate from first principles. Here, compositional complexity is demonstrated as a tunable parameter in a spin-transition oxide semiconductor La1− x(Nd, Sm, Gd, Y)x/4CoO3, by varying the population x of rare earth cations over 0.00≤ x≤ 0.80. Across the series, increasing complexity is revealed to systematically improve crystallinity, increase the amount of electron versus hole carriers, and tune the spin transition temperature and on-off ratio. At high a population (x = 0.8), Seebeck measurements indicate a crossover from hole-majority to electron-majority conduction without the introduction of conventional electron donors, and tunable complexity is proposed as new method to dope semiconductors. First principles calculations combined with angle resolved photoemission reveal an unconventional doping mechanism of lattice distortions leading to asymmetric hole localization over electrons. Thus, tunable complexity is demonstrated as a facile knob to improve crystallinity, tune electronic transitions, and to dope semiconductors beyond traditional means.
PB Wiley
SN 0935-9648
YR 2024
FD 2024
LK https://hdl.handle.net/20.500.14352/111998
UL https://hdl.handle.net/20.500.14352/111998
LA eng
NO A. Zhang, S. Oh, B. K. Choi, E. Rotenberg, T. D. Brown, C. D. Spataru, E. Kinigstein, J. Guo, J. D. Sugar, E. Salagre, A. Mascaraque, E. G. Michel, A. C. Shad, J. Zhu, M. D. Witman, S. Kumar, A. A. Talin, E. J. Fuller, Advanced Materials 2024, 36, 2406885.
NO DE-NA-0003525DE-AC02-05CH11231
NO Ministerio de Ciencia e Innovación (España)
NO European Commission
NO Agencia Estatatal de Investigación (España)
NO Department of Energy (United States)
DS Docta Complutense
RD 16 abr 2025