Skip to Content.
Sympa Menu

fizinfo - [Fizinfo] DE TTK, Szilardtest Fizika Tanszek Szeminarium

fizinfo AT lists.kfki.hu

Subject: ELFT HÍRADÓ

List archive

[Fizinfo] DE TTK, Szilardtest Fizika Tanszek Szeminarium


Chronological Thread 
  • From: Zoltan Erdelyi <zerdelyi AT dragon.klte.hu>
  • To: fizinfo AT lists.kfki.hu
  • Subject: [Fizinfo] DE TTK, Szilardtest Fizika Tanszek Szeminarium
  • Date: Tue Sep 9 14:37:05 2003
  • List-archive: <http://sunserv.kfki.hu/pipermail/fizinfo/>
  • List-id: ELFT HRAD <fizinfo.lists.kfki.hu>

***************************************************

Debreceni Egyetem
Szilardtest Fizika Tanszek

SZEMINARIUM

idopont
-------
2003. szeptember 12., pentek, 11:00 ora

Helyszin
--------
4032 Debrecen, Egyetem ter 1.
Foepulet I. terem

Program
-------

Design of Phase change media for optical and electronic applications

Prof. Matthias Wuttig

Lehrstuhl für Physik neuer Materialien (IA)
1. Physikalisches Institut der RWTH Aachen
D 52056 Aachen, Germany

At present, phase change media that can met the increasing demands of modern storage technology are developed in industrial and university labs by employing experimental optimization schemes. Here we present an alternate approach, which is based upon the combination of combinatorial techniques to produce sample libraries and ab initio calculations of the ground state structure and the electronic respectively optical properties of binary and ternary Tellurium alloys. For a large number of samples it could be shown that only those samples with a particular group of structures enable phase change recording. All materials that show the required optical contrast between the amorphous and crystalline state had cubic or near-cubic structures, while materials based upon tetrahedral structures showed insufficient contrast. The different behavior of these two groups of materials can be explained in part by density functional theory which has been employed to determine the density of states, the band structure and the total energy for different structures of GeTe and GeSbTe based alloys as well as ternary alloys containing Ag, In, Sb and Te. The calculations show a variation of ground state structures and bonding types with stoichiometry. Understanding the observed trends promises the directed optimization of future phase change media for optical and electronic applications. Future challenges for the development of ultra-fast media will be discussed. Our present work provides encouraging evidence that switching in considerably less than 10 ns is already possible and switching times as low as 1 ns should be within reach.

Contributions by Ralf Detemple, Daniel Wamwangi, Stefan Ziegler, Zheru Zhang, Henning Dieker, Meng-Bo Luo, Martina Müller and Woijiech Welnic are gratefully acknowledged.


Presenting author:

Prof. Dr. Matthias Wuttig
Lehrstuhl für Physik neuer Materialien (IA)
1. Physikalisches Institut der RWTH Aachen
D 52056 Aachen, Germany
Phone: 01149-241-8027155
FAX: 01149-241-8022331
E-Mail:
wuttig AT physik.rwth-aachen.de



***************************************************




Archive powered by MHonArc 2.6.19+.

Top of Page