TY - JOUR
T1 - Light-induced metastability in pure and hydrogenated amorphous silicon
AU - Queen, D. R.
AU - Liu, X.
AU - Karel, J.
AU - Wang, Q.
AU - Crandall, R.S.
AU - Metcalf, T.H.
AU - Hellman, F.
PY - 2015
Y1 - 2015
N2 - Light soaking is found to increase the specific heat C and internal friction Q −1 of pure (a-Si) and hydrogenated (a-Si:H) amorphous silicon. At the lowest temperatures, the increases in C and Q −1 are consistent with an increased density of two-level systems (TLS). The light-induced increase in C persists to room temperature. Neither the sound velocity nor shear modulus change with light soaking indicating that the Debye specific heat is unchanged which suggests that light soaking creates localized vibrational modes in addition to TLS. The increase can be reversibly added and removed by light soaking and annealing, respectively, suggesting that it is related to the Staebler-Wronski effect (SWE), even in a-Si without H, and involves a reversible nanoscale structural rearrangement that is facilitated by, but does not require, H to occur.
AB - Light soaking is found to increase the specific heat C and internal friction Q −1 of pure (a-Si) and hydrogenated (a-Si:H) amorphous silicon. At the lowest temperatures, the increases in C and Q −1 are consistent with an increased density of two-level systems (TLS). The light-induced increase in C persists to room temperature. Neither the sound velocity nor shear modulus change with light soaking indicating that the Debye specific heat is unchanged which suggests that light soaking creates localized vibrational modes in addition to TLS. The increase can be reversibly added and removed by light soaking and annealing, respectively, suggesting that it is related to the Staebler-Wronski effect (SWE), even in a-Si without H, and involves a reversible nanoscale structural rearrangement that is facilitated by, but does not require, H to occur.
UR - http://www.scopus.com/inward/record.url?scp=85043518029&partnerID=8YFLogxK
U2 - 10.1209/0295-5075/112/26001
DO - 10.1209/0295-5075/112/26001
M3 - Article
AN - SCOPUS:85043518029
VL - 112
JO - EPL
JF - EPL
SN - 0295-5075
IS - 2
M1 - 26001
ER -