Showing papers by "Ren-Min Ma published in 2018"
TL;DR: This levitated nanodumbbell torsion balance is a novel analog of the Cavendish torsION balance, and provides rare opportunities to observe the Casimir torque and probe the quantum nature of gravity as proposed recently.
Abstract: Levitated optomechanics has great potential in precision measurements, thermodynamics, macroscopic quantum mechanics, and quantum sensing. Here we synthesize and optically levitate silica nanodumbbells in high vacuum. With a linearly polarized laser, we observe the torsional vibration of an optically levitated nanodumbbell. This levitated nanodumbbell torsion balance is a novel analog of the Cavendish torsion balance, and provides rare opportunities to observe the Casimir torque and probe the quantum nature of gravity as proposed recently. With a circularly polarized laser, we drive a 170-nm-diameter nanodumbbell to rotate beyond 1 GHz, which is the fastest nanomechanical rotor realized to date. Smaller silica nanodumbbells can sustain higher rotation frequencies. Such ultrafast rotation may be used to study material properties and probe vacuum friction.
248 citations
TL;DR: A photodetector based on SC-TF perovskite active layer is reported with a record performance of a 50 million gain, 70 GHz gain-bandwidth product, and a 100-photon level detection limit at 180 Hz modulation bandwidth, which as far as the authors know are the highest values among all the reported perov Skites.
Abstract: The best performing modern optoelectronic devices rely on single-crystalline thin-film (SC-TF) semiconductors grown epitaxially. The emerging halide perovskites, which can be synthesized via low-cost solution-based methods, have achieved substantial success in various optoelectronic devices including solar cells, lasers, light-emitting diodes, and photodetectors. However, to date, the performance of these perovskite devices based on polycrystalline thin-film active layers lags behind the epitaxially grown semiconductor devices. Here, a photodetector based on SC-TF perovskite active layer is reported with a record performance of a 50 million gain, 70 GHz gain-bandwidth product, and a 100-photon level detection limit at 180 Hz modulation bandwidth, which as far as we know are the highest values among all the reported perovskite photodetectors. The superior performance of the device originates from replacing polycrystalline thin film by a thickness-optimized SC-TF with much higher mobility and longer recombination time. The results indicate that high-performance perovskite devices based on SC-TF may become competitive in modern optoelectronics.
219 citations
TL;DR: The demonstrated high external quantum efficiency of plasmonic nanolasers not only clarifies the long-standing debate, but also endorses the exploration of them in various practical applications such as near-field spectroscopy and sensing, integrated optical interconnects, solid-state lighting, and free-space optical communication.
Abstract: Plasmonic nanolasers break the diffraction limit for an optical oscillator, which brings new capabilities for various applications ranging from on-chip optical interconnector to biomedical sensing and imaging. However, the inevitably accompanied metallic absorption loss could convert the input power to heat rather than radiations, leading to undesired low external quantum efficiency and device degradation. To date, direct characterization of quantum efficiency of plasmonic nanolasers is still a forbidden task due to its near-field surface plasmon emissions, divergent emission profile, and the limited emission power. Here, we develop a method to characterize the external quantum efficiency of plasmonic nanolasers by synergizing experimental measurement and theoretical calculation. With systematical device optimization, we demonstrate high performance plasmonic nanolasers with external quantum efficiency exceeding 10% at room temperature. This work fills in a missing yet essential piece of key metrics of pl...
37 citations
TL;DR: In this paper, the first deterministic transfer of perovskite nanocrystals with sub-micron accuracy was reported, which can be extended to a variety of other arbitrary substrates (e.g., electrodes, photonic structures, micromechanical systems).
Abstract: Solid-state perovskite nanocrystals are promising coherent light sources, as there is optical feedback within the crystal structure. In order to utilize the high performance of perovskites for on-chip applications, or observe new physical phenomena, these crystals must be integrated with pre-fabricated electronic or photonic structures. However, the materials fragility has made the deterministic transfer a great challenge thus far. Here, we report the first deterministic transfer of perovskite nanocrystals with sub-micron accuracy. Cesium lead halide (CsPbI3) nanocrystals were directly synthesized on flexible polydimethylsiloxane (PDMS) stamps via chemical vapor deposition (CVD) and subsequently transferred onto arbitrary substrates/structures. We demonstrated the transfer of a CsPbI3 crystalline nanoplate (NP) onto an 8 µm fiber core and achieved single-mode whispering gallery mode lasing. Our method can be extended to a variety of other arbitrary substrates (e.g., electrodes, photonic structures, micromechanical systems), laying the foundations for previously unattainable opportunities in perovskites-based devices.
9 citations
TL;DR: In this paper, the authors systematically characterize the lasing properties of plasmonic nanolasers in spatial, momentum, and frequency spaces simultaneously via leakage radiation microscopy and demonstrate a method to identify the exact lasing modes in a multimode PLASMIC nanolaser.
Abstract: Plasmonic nanolasers are a new class of laser device where surface plasmons are amplified by the stimulated emission in a plasmonic nanocavity. In contrast to conventional lasers, the physical size and the mode volume of plasmonic nanolasers can shrink beyond the optical diffraction limit. The strongly confined optical field leads to high performance of plasmonic nanolasers including ultrafast modulation speed and ultralow power consumption, while on another hand introduces challenges in characterizing their basic lasing properties. In this paper, we systematically characterize the lasing properties of plasmonic nanolasers in spatial, momentum, and frequency spaces simultaneously via leakage radiation microscopy and demonstrate a method to identify the exact lasing modes in a multimode plasmonic nanolaser. This paper advances the understanding of lasing emission behavior in plasmonic nanolasers and paves the way for intentionally manipulating their emission for various applications of on-chip nanophotonic circuits, nonlinear nanophotonics, sensing, and imaging.
6 citations
13 May 2018
TL;DR: In this article, a metamaterial engineered chiral plasmonic nanocavity (CPN) was proposed to twist single emitter radiation to vortex beams with controllable topological charge.
Abstract: We propose a metamaterial engineered chiral plasmonic nanocavity (CPN) that, for the first time to our knowledge, can twist single emitter radiation to vortex beams with controllable topological charge.
4 citations
13 May 2018
TL;DR: In this paper, the authors report unusual scaling laws allowing plasmonic lasers with superior performance over photonic lasers at the nanoscale, which clarifies the long-standing debate over the viability of metal confinement and feedback strategies in laser technology.
Abstract: We report unusual scaling laws allowing plasmonic lasers with superior performances over photonic lasers at the nanoscale, which clarifies the long-standing debate over the viability of metal confinement and feedback strategies in laser technology.
1 citations