Atomistic Origin of Urbach Tails in Amorphous Silicon
نویسندگان
چکیده
منابع مشابه
Atomistic origin of urbach tails in amorphous silicon.
Exponential band edges have been observed in a variety of materials, both crystalline and amorphous. In this Letter, we infer the structural origins of these tails in amorphous and defective crystalline Si by direct calculation with current ab initio methods. We find that exponential tails appear in relaxed models of diamond silicon with suitable extended defects that emerge from relaxing point...
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ژورنال
عنوان ژورنال: Physical Review Letters
سال: 2008
ISSN: 0031-9007,1079-7114
DOI: 10.1103/physrevlett.100.206403