2017/03/22 by Miguel Montes Bajo, Julen Tamayo‐Arriola, Bajo, M. Montes +17
Materials Science · #Electronic and Structural Properties of Oxides #FOS: Physical sciences #Magnetic and transport properties of perovskites and related materials #Materials Science (cond-mat.mtrl-sci) #Mesoscale and Nanoscale Physics (cond-mat.mes-hall) #Optics (physics.optics) #Other Condensed Matter (cond-mat.other) #ZnO doping and properties
paper · pdf · doi:10.48550/arxiv.1703.07743
openalex publication_date 2017/03/22 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Intersubband (ISB) polarons result from the interaction of an ISB transition and the longitudinal optical (LO) phonons in a semiconductor quantum well (QW). Their observation requires a very dense two dimensional electron gas (2DEG) in the QW and a polar or highly ionic semiconductor. Here we show that in ZnO/MgZnO QWs the strength of such a coupling can be as high as 1.5 times the LO-phonon frequency due to the very dense 2DEG achieved and the large difference between the static and high-frequency dielectric constants in ZnO. The ISB polaron is observed optically in multiple QW structures with 2DEG densities ranging from 5× 1012 to 5× 1013 cm-2, where an unprecedented regime is reached in which the frequency of the upper ISB polaron branch is three times larger than that of the bare ISB transition. This study opens new prospects to the exploitation of oxides in phenomena happening in the ultrastrong coupling regime.