Femtosecond saturable absorption recovery in a type-II tunneling Bi-quantum well for long-wavelength operation

Y. Matsui, K. Ogawa, Atsushi Tackeuchi, Y. Ogawa, A. Suzuki

    Research output: Contribution to journalArticle


    We demonstrate femtosecond bleached absorption recovery using a type-II tunneling biquantum well (TBQ) structure tailored for long-wavelength operation. The type-II TBQ structure consisted of strained-layer InGaAlAs narrow wells and InGaAsP wide wells with staggered band lineup, separated by thin InAlAs barriers. In the structures, the photocreated electrons in InGaAlAs layers energetically relax to InGaAsP layers via LO-phonon assisted tunneling through InAlAs barrier, resulting in the bleaching recovery due to the ultrafast spatial separation of electrons and holes. The bleached absorption recovery time was as fast as 350 fs in the excitation wavelength range of 50 nm near the InGaAlAs bandgap.

    Original languageEnglish
    Pages (from-to)416-419
    Number of pages4
    JournalPhysica Status Solidi (B) Basic Research
    Issue number1
    Publication statusPublished - 1997 Nov


    ASJC Scopus subject areas

    • Electronic, Optical and Magnetic Materials
    • Condensed Matter Physics

    Cite this