Applications of nanolasers Ma, Ren-Min; Oulton, Rupert F
Nature nanotechnology,
01/2019, Volume:
14, Issue:
1
Journal Article
Peer reviewed
Nanolasers generate coherent light at the nanoscale. In the past decade, they have attracted intense interest, because they are more compact, faster and more power-efficient than conventional lasers. ...Thanks to these capabilities, nanolasers are now an emergent tool for a variety of practical applications. In this Review, we explain the intrinsic merits of nanolasers and assess recent progress on their applications, particularly for optical interconnects, near-field spectroscopy and sensing, optical probing for biological systems and far-field beam synthesis through near-field eigenmode engineering. We highlight the scientific and engineering challenges that remain for forging nanolasers into powerful tools for nanoscience and nanotechnology.
Single-mode laser by parity-time symmetry breaking Feng, Liang; Wong, Zi Jing; Ma, Ren-Min ...
Science (American Association for the Advancement of Science),
11/2014, Volume:
346, Issue:
6212
Journal Article
Peer reviewed
Effective manipulation of cavity resonant modes is crucial for emission control in laser physics and applications. Using the concept of parity-time symmetry to exploit the interplay between gain and ...loss (i.e., light amplification and absorption), we demonstrate a parity-time symmetry–breaking laser with resonant modes that can be controlled at will. In contrast to conventional ring cavity lasers with multiple competing modes, our parity-time microring laser exhibits intrinsic single-mode lasing regardless of the gain spectral bandwidth. Thresholdless parity-time symmetry breaking due to the rotationally symmetric structure leads to stable single-mode operation with the selective whispering-gallery mode order. Exploration of parity-time symmetry in laser physics may open a door to next-generation optoelectronic devices for optical communications and computing.
In order to understand the signal detection design of large-scale MIMO physical layer spatial optical communication systems, the author proposes a research on signal detection of large-scale MIMO ...physical layer spatial optical communication systems based on genetic algorithms. Firstly, the author introduces the basic principles of large-scale MIMO physical layer spatial optical communication systems, analyzes signal detection issues and their challenges. Secondly, a nitty gritty acquaintance was given with hereditary calculation and its application in signal recognition. A genetic algorithm-based signal detection technology scheme was developed for MIMO-OFDM systems. The GA algorithm was contrasted with the ML algorithm and the BLAST algorithm to comprehend its performance. The following parameters served as the foundation for the outcomes of the simulation: The quantity of subcarriers in OFDM is K = 18, and the quantity of images sent per transporter is 165; Additionally, simulation was used to demonstrate how the genetic algorithm affected the MIMO-OFDM system's signal detection. Subsequent to concentrating on the location calculations in MIMO-OFDM frameworks, hereditary calculations are applied to flag discovery in MIMO-OFDM frameworks, to accomplish a decent split the difference among execution and computational intricacy.
Topological insulators are materials that behave as insulators in the bulk and as conductors at the edge or surface due to the particular configuration of their bulk band dispersion. However, up to ...date possible practical applications of this band topology on materials' bulk properties have remained abstract. Here, we propose and experimentally demonstrate a topological bulk laser. We pattern semiconductor nanodisk arrays to form a photonic crystal cavity showing topological band inversion between its interior and cladding area. In-plane light waves are reflected at topological edges forming an effective cavity feedback for lasing. This band-inversion-induced reflection mechanism induces single-mode lasing with directional vertical emission. Our topological bulk laser works at room temperature and reaches the practical requirements in terms of cavity size, threshold, linewidth, side-mode suppression ratio and directionality for most practical applications according to Institute of Electrical and Electronics Engineers and other industry standards. We believe this bulk topological effect will have applications in near-field spectroscopy, solid-state lighting, free-space optical sensing and communication.
Ultralow-threshold plasmonic lasers under continuous-wave pumping at room temperature have been created using lattice plasmonic cavities integrated with gain material consisting of upconverting ...nanoparticles.
•Growth factor signaling causes sustained nuclear ERK1/2 activation.•The SCR and BCR/ABL inhibitor dasatinib blocks ERK1/2 and represses cell invasion.•EGF-stimulated cells may escape dasatinib ...inhibition of invasion through mesenchymal to amoeboid transition.•Combined inhibition of SRC and Rho-kinase signaling is necessary to completely block EGF-induced invasion.
Aberrantly activated kinase signaling pathways drive invasion and dissemination in medulloblastoma (MB). A majority of tumor-promoting kinase signaling pathways feed into the mitogen-activated protein kinase (MAPK) extracellular regulated kinase (ERK1/2) pathway. The activation status of ERK1/2 during invasion of MB cells is not known and its implication in invasion control unclear.
We established a synthetic kinase activation relocation sensor (SKARS) for the MAPK ERK1/2 pathway in MB cells for real-time measuring of drug response. We used 3D invasion assays and organotypic cerebellum slice culture to test drug effects in a physiologically relevant tissue environment.
We found that hepatocyte growth factor (HGF), epidermal growth factor (EGF), or basic fibroblast growth factor (bFGF) caused rapid nuclear ERK1/2 activation in MB cells, which persisted for several hours. Concomitant treatment with the BCR/ABL kinase inhibitor dasatinib completely repressed nuclear ERK1/2 activity induced by HGF and EGF but not by bFGF. Increased nuclear ERK1/2 activity correlated positively with speed of invasion. Dasatinib blocked ERK-associated invasion in the majority of cells, but we also observed fast-invading cells with low ERK1/2 activity. These ERK1/2-low, fast-moving cells displayed a rounded morphology, while ERK-high fast-moving cells displayed a mesenchymal morphology. Dasatinib effectively blocked EGF-induced proliferation while it only moderately repressed tissue invasion, indicating that a subset of cells may evade invasion repression by dasatinib through non-mesenchymal motility. Thus, growth factor-induced nuclear activation of ERK1/2 is associated with mesenchymal motility and proliferation in MB cells and can be blocked with the BCR/ABL kinase inhibitor dasatinib.
The radiation of electromagnetic and mechanical waves depends not only on the intrinsic properties of the emitter but also on the surrounding environment. This principle has laid the foundation for ...the development of lasers, quantum optics, sonar, musical instruments and other fields related to wave–matter interaction. In the conventional wisdom, the environment is defined exclusively by its eigenstates, and an emitter radiates into and interacts with these eigenstates. Here we show experimentally that this scenario breaks down at a non-Hermitian degeneracy known as an exceptional point. We find a chirality-reversal phenomenon in a ring cavity where the radiation field reveals the missing dimension of the Hilbert space, known as the Jordan vector. This phenomenon demonstrates that the radiation field of an emitter can become fully decoupled from the eigenstates of its environment. The generality of this striking phenomenon in wave–matter interaction is experimentally confirmed in both electromagnetic and acoustic systems. Our finding transforms the fundamental understanding of light–matter interaction and wave–matter interaction in general, and enriches the intriguing physics of exceptional points.The modes of the radiation field generated from an emitter are usually determined by the eigenstates of the surrounding environment. However, this scenario breaks down in a non-Hermitian system, at the spectral degeneracy known as an exceptional point.
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