Antiferromagnetic Semiconductor BaFMn 0.5 Te with Unique Mn Ordering and Red Photoluminescence

Semiconductors possessing both magnetic and optoelectronic properties are rare and promise applications in opto-spintronics. Here we report the mixed-anion semiconductor BaFMn Te with a band gap of 1.76 eV and a work function of 5.08 eV, harboring both antiferromagnetism (AFM) and strong red photolu...

Ausführliche Beschreibung

Gespeichert in:
Bibliographische Detailangaben
Veröffentlicht in:Journal of the American Chemical Society 2019-10, Vol.141 (43), p.17421-17430
Hauptverfasser: Chen, Haijie, McClain, Rebecca, He, Jiangang, Zhang, Chi, Olding, Jack N, Dos Reis, Roberto, Bao, Jin-Ke, Hadar, Ido, Spanopoulos, Ioannis, Malliakas, Christos D, He, Yihui, Chung, Duck Young, Kwok, Wai-Kwong, Weiss, Emily A, Dravid, Vinayak P, Wolverton, Christopher, Kanatzidis, Mercouri G
Format: Artikel
Sprache:eng
Online-Zugang:Volltext
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
Beschreibung
Zusammenfassung:Semiconductors possessing both magnetic and optoelectronic properties are rare and promise applications in opto-spintronics. Here we report the mixed-anion semiconductor BaFMn Te with a band gap of 1.76 eV and a work function of 5.08 eV, harboring both antiferromagnetism (AFM) and strong red photoluminescence (PL). The synthesis of BaFMn Te in quantitative yield was accomplished using the "panoramic synthesis" technique and synchrotron radiation to obtain the full reaction map, from which we determined that the compound forms upon heating at 850 °C via an intermediate unknown phase. The structure refinement required the use of a (3+1)-dimensional superspace group (α01/2)0 . The material crystallizes into a ZrCuSiAs-like structure with alternating [BaF] and [Mn Te] layers and has a commensurately modulated structure with the -vector of 1/6 * + 1/6 * + 1/2 * at room temperature arising from the unique ordering pattern of Mn cations. Long-range AFM order emerges below 90 K, with two-dimensional short-range AFM correlations above the transition temperature. First-principles calculations indicate that BaFMn Te is an indirect band gap semiconductor with the gap opening between Te 5 and Mn 3 orbitals, and the magnetic interactions between nearest-neighbor Mn atoms are antiferromagnetic. Steady-state PL spectra show a broad strong emission centered at ∼700 nm, which we believe originates from the energy manifolds of the modulated Mn sublattice and its defects. Time-resolved PL measurements reveal an increase in excited-state lifetimes with longer probe wavelengths, from 93 ns (at 650 nm) to 345 ns (at 800 nm), and a delayed growth (6.5 ± 0.3 ns) in the kinetics at 800 nm with a concomitant decay (4.1 ± 0.1 ns) at 675 nm. Together, these observations suggest that there are multiple emissive states, with higher energy states populating lower energy states by energy transfer.
ISSN:0002-7863
1520-5126
DOI:10.1021/jacs.9b09382