Light-Induced Metastability in Pure and Hydrogenated Amorphous Silicon: Article No. 26001

D. Queen, X. Liu, J. Karel, Q. Wang, T. Metcalf, F. Hellman

    Research output: Contribution to journalArticlepeer-review

    3 Scopus Citations


    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.
    Original languageAmerican English
    Number of pages6
    JournalEurophysics Letters
    Issue number2
    StatePublished - 2015

    NREL Publication Number

    • NREL/JA-5200-67330


    • amorphous semiconductors
    • light soaking
    • metastability


    Dive into the research topics of 'Light-Induced Metastability in Pure and Hydrogenated Amorphous Silicon: Article No. 26001'. Together they form a unique fingerprint.

    Cite this