Two-Dimensional Semiconductor Microcavity Laser

Min-Hsiung Shih^1*

¹Research Center for Applied Sciences, Academia Sinica, Taipei, Taiwan
²Department of Photonics, National Yang Ming Chiao Tung University, Hsinchu, Taiwan
³Department of Photonics, National Sun Yat-Sen University, Kaohsiung, Taiwan

* Presenter:Min-Hsiung Shih, email:mhshih@gate.sinica.edu.tw

Monolayered (ML) transition metal dichalcogenide (TMDC) is known as a
promising gain material for realizing compact and low-threshold lasers that can be
operated at room temperature. In our studies, we demonstrate two types of ML TMDC-
based microcavity lasers that represent important progress toward practical two-
dimensional laser devices. First, we develop a hybrid laser by integrating ML WSe2
with cadmium selenide (CdSe) quantum dots (QDs) in a single microdisk cavity. This
hybrid structure achieves dual-color lasing and enhances the lasing performance of ML
WSe2 through energy transfer between the two gain materials, resulting in a more than
2.5 times of lasing threshold reduction. Furthermore, we realize the first electrically-
driven ML TMDC microcavity laser, in which alternating current (AC) excitation
induces electroluminescence lasing from a ML WSe2 on a gap microdisk. We carefully
control the carriers’ recombination on the suspended ML WSe2 by precisely tuning the
structure dimension. The lasing behavior is confirmed by the input-output curve,
linewidth narrowing, and second-order coherence measurements. These results
highlight both optical and electrical approaches on improvements of ML TMDC-based
compact lasers and demonstrate their strong potential for future integrated photonic and
optoelectronic applications

Keywords: 2-D materials , Microcavity laser, Atom photon interactions , Transition-metal dichalcogenide (TMDC)