TY - JOUR
KW - paper
AU - W Welnic
AU - Silvana Botti
AU - Lucia Reining
AU - Matthias Wuttig
AB - Several chalcogenide alloys exhibit a pronounced contrast between the optical absorption in the metastable rocksalt and in the amorphous phase. This phenomenon is the basis for their application in optical data storage. Here we present ab initio calculations of the optical properties of GeTe and Ge1Sb2Te4 in the two phases. The analysis of our computations and experimental data reveal the correlation between local structural changes and optical properties as well as the origin of the optical contrast in these materials. We find that the change in optical properties cannot be attributed to a smearing of transition energies as commonly assumed for amorphous semiconductors: the optical contrast between the two phases can only be explained by significant changes in the transition matrix elements.
BT - Phys. Rev. Lett.
CY - ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA
DA - JUN 8
DO - 10.1103/PhysRevLett.98.236403
M1 - 23
N2 - Several chalcogenide alloys exhibit a pronounced contrast between the optical absorption in the metastable rocksalt and in the amorphous phase. This phenomenon is the basis for their application in optical data storage. Here we present ab initio calculations of the optical properties of GeTe and Ge1Sb2Te4 in the two phases. The analysis of our computations and experimental data reveal the correlation between local structural changes and optical properties as well as the origin of the optical contrast in these materials. We find that the change in optical properties cannot be attributed to a smearing of transition energies as commonly assumed for amorphous semiconductors: the optical contrast between the two phases can only be explained by significant changes in the transition matrix elements.
PB - AMERICAN PHYSICAL SOC
PP - ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA
PY - 2007
EP - 236403
T2 - Phys. Rev. Lett.
TI - Origin of the optical contrast in phase-change materials
UR - http://dx.doi.org/10.1103/PhysRevLett.98.236403
VL - 98
ER -