J 2016

Infrared ellipsometry study of the confined electrons in a high-mobility gamma-Al2O3/SrTiO3 heterostructure

YAZDI-RIZI, M., Přemysl MARŠÍK, B. P. P. MALLETT, Adam DUBROKA, D. V. CHRISTENSEN et. al.

Basic information

Original name

Infrared ellipsometry study of the confined electrons in a high-mobility gamma-Al2O3/SrTiO3 heterostructure

Authors

YAZDI-RIZI, M. (364 Islamic Republic of Iran), Přemysl MARŠÍK (203 Czech Republic), B. P. P. MALLETT (554 New Zealand), Adam DUBROKA (203 Czech Republic, guarantor, belonging to the institution), D. V. CHRISTENSEN (208 Denmark), Y. Z. CHEN (156 China), N. PRYDS (208 Denmark) and Christian BERNHARD (276 Germany)

Edition

EPL, MULHOUSE, EPL ASSOCIATION, EUROPEAN PHYSICAL SOCIETY, 2016, 0295-5075

Other information

Language

English

Type of outcome

Článek v odborném periodiku

Field of Study

10302 Condensed matter physics

Country of publisher

France

Confidentiality degree

není předmětem státního či obchodního tajemství

Impact factor

Impact factor: 1.957

RIV identification code

RIV/00216224:14310/16:00093796

Organization unit

Faculty of Science

UT WoS

000372420000021

Keywords in English

nfrared ellipsometry; Al2O3/SrTiO3 heterostructure

Tags

Tags

International impact, Reviewed
Změněno: 13/3/2018 16:10, doc. Mgr. Adam Dubroka, Ph.D.

Abstract

V originále

With infrared ellipsometry we studied the response of the confined electrons in gamma-Al2O3/SrTiO3 (GAO/STO) heterostructures in which they originate predominantly from oxygen vacancies. From the analysis of a so-called Berreman mode, that develops near the highest longitudinal optical phonon mode of SrTiO3, we derive the sheet carrier density, N-s, the mobility, mu, and the depth profile of the carrier concentration. Notably, we find that N-s and the shape of the depth profile are similar as in LaAlO3/SrTiO3 (LAO/STO) heterostructures for which the itinerant carriers are believed to arise from a polar discontinuity. Despite an order of magnitude higher mobility in GAO/STO, as obtained from transport measurements, the derived mobility in the infrared range exhibits only a twofold increase. We interpret this finding in terms of the polaronic nature of the confined charge carriers in GAO/STO and LAO/STO which leads to a strong, frequency-dependent interaction with the STO phonons. Copyright (C) EPLA, 2016

Links

ED1.1.00/02.0068, research and development project
Name: CEITEC - central european institute of technology