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Laser cavity-solitons can appear in systems comprised of a nonlinear microcavity nested within an amplifying fiber loop. These states are robust and self-emergent and constitute an attractive class of solitons that are highly suitable for microcomb generation. Here, we present a detailed study of the free-running stability properties of the carrier frequency and repetition rate of single solitons, which are the most suitable states for developing robust ultrafast and high repetition rate comb sources. We achieve free-running fractional stability on both optical carrier and repetition rate (i.e., 48.9 GHz) frequencies on the order of [Formula: see text] for a 1 s gate time. The repetition rate results compare well with the performance of state-of-the-art (externally driven) microcomb sources, and the carrier frequency stability is in the range of performance typical of modern free-running fiber lasers. Finally, we show that these quantities can be controlled by modulating the laser pump current and the cavity length, providing a path for active locking and long-term stabilization.

The use of dasatinib and nilotinib in the treatment of patients with chronic myeloid leukemia represents a valid therapeutic option for patients resistant or intolerant to imatinib. In this multicentre study, adherence, persistence and efficacy in real life over two years of treatment were evaluated.Adherence to treatment was calculated as the ratio between the dose received and the prescribed dose. The dose received was calculated using pharmacy refill data. The persistence with treatment was calculated as the difference between the end and the beginning of the treatment. Efficacy was assigned as Progression-Free Survival (PFS) and Events-Free Survival (EFS) and represented through the Kaplan-Meier curve.The number of patients analysed was 117, 70 treated with dasatinib and 47 with nilotinib. Adherence to treatment for dasatinib and nilotinib at two years was 0.91 and 0.82 respectively. Persistence at two years was 77% while the PFS was 92% for both drugs in the study.Adherence to the treatment calculated over two years showed a superiority of dasatinib over nilotinib. Nevertheless, the efficacy in terms of PFS and EFS is superimposable between the two drugs in the study.

In many disciplines, states that emerge in open systems far from equilibrium are determined by a few global parameters1,2. These states can often mimic thermodynamic equilibrium, and a classic example of this is the oscillation threshold of a laser3, which resembles a phase transition in condensed matter. However, many relevant classes of states cannot form spontaneously in dissipative systems, and this is the case for cavity-solitons2 that generally need to be induced by external perturbations, as in the case of optical memories4,5. In the last decade, these highly localised states have enabled significant advancements in microresonator-based optical frequency combs6,7. However, the very advantages that make cavity-solitons attractive for memories – their inability to form spontaneously from noise – have created fundamental challenges. To be reliable sources, microcombs require the essential features of starting laser oscillation naturally, spontaneously and reliably, and of operating in a desired specific state that is intrinsically robust. Largely because of the intrinsic nature of cavity-solitons, these goals have remained elusive8–20. Here, we show that slow nonlinearities of a free-running microresonator-filtered fibre laser21 can transform temporal cavity-solitons into the dominant attractor of the system. This phenomenon leads to reliable self-starting oscillation of (single and multiple) micro cavity-solitons that, in addition, are naturally robust to perturbations, recovering spontaneously even after a complete disruption. These emerge repeatably and controllably into a large region of the global system parameter space, where specific states can be achieved, and which we show are highly stable over long timeframes. These features are all critically needed for the practical implementation of microcombs outside the laboratory.

Slow nonlinearities are critical in microresonator-based frequency combs, regulating essential phenomena, from stability to soliton starting and formation. We discuss their effect in a microresonator-filtered fiber laser.

We present a theoretical/experimental investigation of broadband, spatiotemporal superfocusing (SF) and field-modulation of ultrafast terahertz (THz) waves in scattering media combining the nonlinear conversion of spatially modulated ultrashort pulses with THz time-domain field detection.

We show the free-running frequency stability and the frequency control of a micro-comb system comprising a micro-ring nested into an amplifying fibre cavity.

Scattering-assisted synthesis of broadband optical pulses is recognized to have a cross-disciplinary fundamental and application importance. Achieving full-waveform synthesis generally requires means for assessing the instantaneous electric field, i.e., the absolute electromagnetic phase. These are generally not accessible to established methodologies for scattering-assisted pulse envelope and phase shaping. The lack of field sensitivity also results in complex indirect approaches to evaluate the scattering space–time properties. The terahertz frequency domain potentially offers some distinctive new possibilities, thanks to the availability of methods to perform absolute measurements of the scattered electric field, as opposed to optical intensity-based diagnostics. An interesting conceptual question is whether this additional degree of freedom can lead to different types of methodologies toward wave shaping and direct field-waveform control. In this work, we theoretically investigate a deterministic scheme to achieve broadband, spatiotemporal waveform control of terahertz fields mediated by a scattering medium. Direct field access via time-domain spectroscopy enables a process in which the field and scattering matrix of the medium are assessed with minimal experimental efforts. Then, illumination conditions for an arbitrary targeted output field waveform are deterministically retrieved through numerical inversion. In addition, complete field knowledge enables reconstructing field distributions with complex phase profiles, as in the case of phase-only masks and optical vortices, a significantly challenging task for traditional implementations at optical frequencies based on intensity measurements aided with interferometric techniques.

Terahertz near-field microscopy represents a remarkable challenge, deeply limited by diffraction. With our technique; time-resolved nonlinear ghost-imaging, we demonstrate that spatio-temporal coupling affecting subwavelength measurements can be exploited as a lens, retrieving volumetric hyperspectral insights.

Neurophysiological studies have shown that our motor system plays a fundamental role in the scaffolding of our cognitive system. Taking these findings into account, we have designed and produced manipulatives that reproduce geometric figures. Through them, we can amplify our perception of the relationships between different elements. We believe that repeated interactions with the manipulatives generate the ability to imagine similar movements on drawn figures. An example is "squaring in motion", through which a given figure is transformed into an equivalent rectangle. We verified, through a quantitative study involving preadolescents (12-14 years old), the long-term effectiveness of the use of manipulatives on problem solving.

Harnessing the propagation of ultrafast pulses through complex media is a key challenge in photonics. In this theoretical work, we demonstrate that THz field-sensitive detection enables the broadband and deterministic spatiotemporal control of complex media.