NMR study of native defects in PbSe

Abstract

While each atom species in PbSe corresponds to a single crystallographic site and transport measurements reveal a single carrier density, ${}^{207}$Pb NMR reveals a more complicated picture than previously thought comprising three discrete homogeneous carrier components, each associated with $n$- or $p$-type carrier fractions. The origins of these fractions are discussed in terms of electronic heterogeneity of the native semiconductor. The interaction mechanism between nuclear spins and lattice vibrations via fluctuating spin-rotation interaction, applicable to heavy spin-1/2 nuclei [Phys. Rev. B 74, 214420 (2006)], does not hold. Instead, a higher-order temperature dependence dominates the relaxation pathway. Shallow acceptor states and deep level defects in the midgap explain the complex temperature dependence of the direct band gap.

arXiv comment29 pages, 10 figures

References in corpus (6)

• Topological Insulators
• Topological Crystalline Insulators
• Topological crystalline insulator states in Pb(1-x)Sn(x)Se
• NMR Observation of Rattling Phonons in the Pyrochlore Superconductor KOs2O6
• A combined NMR and DFT study of Narrow Gap Semiconductors: The case of PbTe
• Nuclear-spin relaxation of ${}^{207}$Pb in ferroelectric powders

Cited by in corpus (1)

• Site-Specific Contributions to the Band Inversion in a Topological Crystalline Insulator