On-chip integrated laser sources of structured light carrying fractional orbital angular momentum (FOAM) are highly desirable for the forefront development of optical communication and quantum information–processing technologies. While integrated vortex beam generators have been previously demonstrated in different optical settings, ultrafast control and sweep of FOAM light with low-power control, suitable for high-speed optical communication and computing, remains challenging. Here we demonstrate fast control of the FOAM from a vortex semiconductor microlaser based on fast transient mixing of integer laser vorticities induced by a control pulse. A continuous FOAM sweep between charge 0 and charge +2 is demonstrated in a 100 ps time window, with the ultimate speed limit being established by the carrier recombination time in the gain medium. Our results provide a new route to generating vortex microlasers carrying FOAM that are switchable at GHz frequencies by an ultrafast control pulse.
Metal halide perovskites have drawn tremendous attention in optoelectronic applications owing to the rapid development in photovoltaic and light‐emitting diode devices. More recently, these materials are demonstrated as excellent gain media for laser applications due to their large absorption coefficient, low defect density, high charge carrier mobility, long carrier diffusion length, high photoluminescence quantum yield, and low Auger recombination rate. Despite the great progress in laser applications, the development of perovskite lasers is still in its infancy and the realization of electrically pumped lasers has not yet been demonstrated. To accelerate the development of perovskite‐based lasers, it is important to understand the fundamental photophysical characteristics of perovskite gain materials. Here, the structure and gain behavior in various perovskite materials are discussed. Then, the effects of charge carrier dynamics and electron–phonon interaction on population inversion in different types of perovskite materials are analyzed. Further, recent advances in perovskite‐based lasers are also highlighted. Finally, a perspective on perovskite material design is presented and the remaining challenges of perovskite lasers are discussed.
more » « less- Award ID(s):
- 1729383
- PAR ID:
- 10452993
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Functional Materials
- Volume:
- 31
- Issue:
- 16
- ISSN:
- 1616-301X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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