English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Zendy Plus

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Zendy Tools

Zendy Open

Black phosphorus is emerging as a promising semiconductor for electronic andoptoelectronic applications. To study fundamental carrier properties, weperformed ultrafast femtosecond pump-probe spectroscopy on thin film blackphosphorus mechanically exfoliated on a glass substrate. Carriers (electronsand holes) were excited to high energy levels and the process of carrierrelaxation through phonon emission and recombination was probed. We used a widerange of probing wavelengths up to and across the band gap to study theevolution of the relaxation dynamics at different energy levels. Ourexperiments revealed a plethora of important physical phenomena. The fastrelaxation time constants, associated with carrier-phonon scattering, steadilyincrease as the energy of the probe beam approaches the band gap energy, whichwas determined to be 0.31 eV, and the carrier recombination rate was obtainedwhen the probe wavelength was tuned to match the band gap energy. Thecarrier-phonon scattering rates were found to be similar along the armchair andzigzag directions, therefore, the anisotropic carrier mobility reported inliterature is mainly due to the difference in effective mass of carriers alongdifferent directions. The ultrafast spectroscopy data further revealed theoxidation induced surface charges. Our results highlight the importance ofusing the spectroscopy technique, in this case, in the mid-IR range, to uncoveruseful physical processes.

Mid-Infrared Ultrafast Carrier Dynamics in Thin Film Black Phosphorus