Observation of dispersive wave emission by temporal cavity solitons

We examine a coherently-driven, dispersion-managed, passive Kerr fiber ring resonator and report the first direct experimental observation of dispersive wave emission by temporal cavity solitons. Our observations are in excellent agreement with analytical predictions and they are fully corroborated by numerical simulations. These results lead to a better understanding of the behavior of temporal cavity solitons under conditions where higher-order dispersion plays a significant role. Significantly, since temporal cavity solitons manifest themselves in monolithic microresonators, our results are likely to explain the origins of spectral features observed in broadband Kerr frequency combs.Comment: 4 pages, 3 figure

An all-optical buffer based on temporal cavity solitons operating at 10 Gb/s

We demonstrate the operation of an all-optical buffer based on temporal cavity solitons stored in a nonlinear passive fiber ring resonator. Unwanted acoustic interactions between neighboring solitons are suppressed by modulating the phase of the external laser driving the cavity. A new locking scheme is presented that allows the buffer to operate with an arbitrarily large number of cavity solitons in the loop. Experimentally, we are able to demonstrate the storage of 4536 bits of data, written all-optically into the fiber ring at 10 Gb/s, for 1 minute.Comment: 5 pages, 4 figure

Fundamental noise limitations to supercontinuum generation in microstructure fiber

Broadband noise on supercontinuum spectra generated in microstructure fiber is shown to lead to amplitude fluctuations as large as 50 % for certain input laser pulse parameters. We study this noise using both experimental measurements and numerical simulations with a generalized stochastic nonlinear Schroedinger equation, finding good quantitative agreement over a range of input pulse energies and chirp values. This noise is shown to arise from nonlinear amplification of two quantum noise inputs: the input pulse shot noise and the spontaneous Raman scattering down the fiber.Comment: 16 pages with 6 figure

Private Sector and Climate Change A Case Study of Carbon-Based Governance

Global greenhouse gas emissions are the main contributor to anthropocentrically-induced climate change and have risen 41% since 1990. We are still yet to reach peak emissions. A large share of those emissions result from private sector activity. At the same time, the private sector possesses major resources which should be harnessed to scale up funding and emissions reduction technologies to benefit the 3 climate. Since the Paris Climate Agreement in 2015, there has been an upsurge in private sector activity on climate change, especially in the corporate sector. Researchers have suggested that this groundswell of private sector activity especially in reduction of carbon emissions holds out the promise of plugging conspicuous public governance gaps. But while this surge in private action since the Paris Climate Agreement is to be encouraged, and indeed has been formally welcomed by global public climate governance actors under the UNFCCC, the measurable success of private, public-private and “hybrid” climate governance arrangements on reducing emissions remains unclear. Through an in depth empirical investigation of the actors and initiatives that play a key role in this emerging domain of bottom-up climate change governance, this study finds that, despite a groundswell in private activity, zones of fragmentation among a multiplicity of private actors, initiatives and standards is stymying progress: while key actors are increasingly networked, key metrics remain severely fragmented; while substantial resources have been dedicated to governing carbon emissions, greenhouse gas emissions keep rising. These observations are demonstrated through an empirical analysis of the “carbon-based” governance regime, which we define as the governance of climate change through a unitary focus on carbon measurement, disclosure, and verification. So far, the ultimate goal of carbon-based governance to reduce emissions is far from being realized. Whether this regime can be repurposed to fulfil this crucial function remains an open question