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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.

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.

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.

Laser cavity-soliton microcombs are robust optical pulsed sources, usually implemented with a microresonator-filtered fibre laser. In such a configuration, a nonlinear microcavity converts the narrowband pulse resulting from bandwidth-limited amplification to a background-free broadband microcomb. Here, we theoretically and experimentally study the soliton conversion efficiency between the narrowband input pulse and the two outputs of a four-port integrated microcavity, namely the ‘Drop’ and ‘Through’ ports. We simultaneously measure on-chip, single-soliton conversion efficiencies of 45% and 25% for the two broadband comb outputs at the ‘Drop’ and ‘Through’ ports of a 48.9 GHz free-spectral range micro-ring resonator, obtaining a total conversion efficiency of 72%.

Microcavity-based frequency combs, or ‘microcombs’1,2, have enabled many fundamental breakthroughs3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21 through the discovery of temporal cavity-solitons. These self-localized waves, described by the Lugiato–Lefever equation22, are sustained by a background of radiation usually containing 95% of the total power23. Simple methods for their efficient generation and control are currently being investigated to finally establish microcombs as out-of-the-lab tools24. Here, we demonstrate microcomb laser cavity-solitons. Laser cavity-solitons are intrinsically background-free and have underpinned key breakthroughs in semiconductor lasers22,25,26,27,28. By merging their properties with the physics of multimode systems29, we provide a new paradigm for soliton generation and control in microcavities. We demonstrate 50-nm-wide bright soliton combs induced at average powers more than one order of magnitude lower than the Lugiato–Lefever soliton power threshold22, measuring a mode efficiency of 75% versus the theoretical limit of 5% for bright Lugiato–Lefever solitons23. Finally, we can tune the repetition rate by well over a megahertz without any active feedback.

Microcombs are optical frequency combs based on microcavity resonators [1] . They find multiple applications, including metrology, spectroscopy, frequency synthesis, and optical communications. Temporal cavity solitons (TCS), the temporal counterpart of spatial cavity solitons [2] , have been shown to produce microcombs with optimal spectral features [1] and are well modeled by the Lugiato-Lefever equation in passive systems. High contrast TCS can be also obtained in active systems inclusive of laser gain [3] .

Novel metamaterial platforms exhibiting time-dependent electromagnetic properties enable the investigation of previously unexplored light-matter interactions [1] - [2] . A variation in the dielectric function on a timescale shorter than the electric field period is perceived as an ultrafast temporal boundary [3] , thus resulting in a time-dependent "Snell’s law" which connects the polarisation field frequency before and after the transition [4] , [5] . The onset of a frequency shift therefore enables the engineering of exotic nonlinear phenomena such as time refraction and photon acceleration [5] - [7] , with key fundamental and practical implications [8] . In one scheme, a temporal boundary is induced via photoexcitation of semiconducting metamaterials excited by ultrashort optical pulses. Above-bandgap photons drive an ultrafast transition from a dielectric to a metallic state. Temporal-boundaries-mediated nonlinearities become relevant for transition times shorter than the wave-period timescale, a challenging regime in optics. This condition is achieved in a hybrid approach, exploiting the interaction of terahertz (THz) fields and ultrafast photo-excited transients. The peculiar advantage of THz Time-Domain-Spectroscopy techniques is that they allow the agile reconstruction of full-field dynamics with sub-wave-period resolution. In addition, in all the considered schemes, terahertz waves impinge from vacuum onto a positionally static transient, in other words a large velocity mismatch always exists. An unexplored physical scenario is then when the transient is applied directly to a source where the transient exists in the same positional reference as the THz wave.

A complex problem in terahertz photonics is the need for thin emitters [1] . Traditional free-space terahertz (THz) emission crystals rely on relatively thick crystals (on the orders of millimetres), as the terahertz emission scales with the length of the crystal. Thick crystals, however, come with a number of drawbacks. One such drawback is that the emitted THz bandwidth is limited by phase-matching conditions [2] . This amounts to thicker crystals giving a lower bandwidth, making them unsuitable for broadband spectroscopy. In near-field imaging, the image resolution depends critically on how close one can approach the sample [3] : in this regime, thick crystals can quickly become unpractical as they effectively limit the achievable resolution.

Controlling the propagation of waves in random scattering media is a recurring challenge in several physical settings. Multiple scattering has a ubiquitous impact in wave domains like sound and mechanical [1] , and electromagnetic [2] . A fundamental limitation in the study of random wave propagation is the limited experimental access to the time-resolved oscillations of the electric field. At optical frequencies, in particular, the instantaneous electric field of optical wave-packets is, in general, not a directly measurable quantity, although particular settings, e.g., in the domain of optical frequency combs, allows for indirect reconstruction [3] . Conversely, full-wave characterization is quite mature in the state of the art of ultrafast terahertz (THz) photonics. The possibility of field-sensitive detection raises the important question of whether operating on the time-space domain of the electric field could provide insight on random wave propagate on typically not accessible in the optical domain. Indeed, this scenario recalls, in some fashion, the way random wave propagation is handled in the microwave and ultrasound domains, where multiple-path and scattering modelling allows specific deterministic approaches (e.g., time-reversal). A quite apt example is how the scattering matrix of a complex sample can be retrieved at optical frequency through measurements of the transmitted intensity profile [2] . This approach typically leads to a massive loss of information since scattering operates simultaneously in time and space [4] . However, it is conceivable that a more direct approach can be cast in a domain like THz, where the field is measurable in space and time. This ability would not only have a profound impact on THz imaging as a whole [5] , [6] , but it could also define novel approaches to the imaging of objects hidden behind scattering media while preserving their spectral fingerprint.

In photonics, the study of wave propagation in scattering media is limited by the inherent challenges in detecting the time-varying electric field oscillations, as detectors and cameras are only sensitive to the optical intensity. In the Terahertz (THz) domain, however, Time-Domain Spectroscopy (TDS) is an established technique capable of directly measuring the electric field and provide full-wave characterisation (amplitude and optical delay) in time. The combination of THz time-resolved measurements with the theory of wave propagation in scattering media is a rapidly emerging subject. It opens a promising route to gain coherent control over multiple-scattering phenomena in ways not previously accessible in optics [1] . Besides, the combination of broadband excitation and coherent, field-sensitive detection could allow investigating the transmission properties of a scattering medium in unprecedented detail and retrieve its coherent transfer-matrix representation, a task out-of-reach at optical frequencies. In this work, we theoretically demonstrate spatiotemporal refocusing of THz waves following a direct measurement of the transfer matrix of the scattering medium. Our approach combines the advantages offered by field-sensitive detection with the nonlinear wavefront shaping of THz waves. Wavefront shaping represents the state-of-the-art in the control of complex wave propagation at optical frequencies, as it allows to sequentially retrieve the transfer matrix elements of the scatterer [2] . To overcome the limited availability of THz Spatial Light Modulator (SLM) devices, we employ a recently proposed technique based on the nonlinear conversion of structured optical beams to THz patterns [3] . Specifically, we take inspiration from nonlinear Ghost-Imaging techniques and project a complete set of orthogonal Hadamard patterns on the scatterer [4] . This technique allows us to retrieve the complex-valued elements of the transfer matrix by numerical inversion ( Fig. 1a,b ). We apply the direct knowledge of the transfer matrix elements to identify the optimal focusing pattern in a deterministic fashion ( Fig. 1c,d ). Unlike iterative optimisation techniques [2] , our deterministic approach takes advantage of the full amount of spatiotemporal information encoded in the transfer matrix elements. Under this view, the task of identifying the optimal input wavefront is rewritten into an inverse problem that can be solved via constraint least-square optimisation methods. An exemplary result is shown in Fig. 1c,d , where our technique is employed to achieve spatiotemporal refocusing (i.e., focusing in space and compression in time) of a single cycle THz pulse.

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, a classic example being the oscillation threshold of a laser3 that resembles a phase transition in condensed matter. However, many 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 past decade, these highly localized states have enabled important 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. As sources, microcombs require spontaneous and reliable initiation into a desired state that is intrinsically robust8–20. Here we show that the slow non-linearities of a free-running microresonator-filtered fibre laser21 can transform temporal cavity solitons into the system’s dominant attractor. This phenomenon leads to reliable self-starting oscillation of microcavity solitons that are naturally robust to perturbations, recovering spontaneously even after complete disruption. These emerge repeatably and controllably into a large region of the global system parameter space in which specific states, highly stable over long timeframes, can be achieved.

Solitary waves — solitons — occur in a wide range of physical systems with a broad array of attributes and applications. Carefully engineered light–matter interactions have now produced an optomechanical dissipative soliton with promising properties.

Turing patterns and solitons are a common occurrence in systems that are out of equilibrium. For example, they regulate the emergence of organised structures in biology and chemistry. In optics, the study of temporal Turing rolls and cavity-solitons in nonlinear micro-cavity resonators has been key to the understanding of optical frequency comb formation in these structures. Over a decade, the impact of microresonator-based approaches to generating frequency combs – so-called "Micro-combs or "Kerr combs" – has reached far beyond metrology applications. Here we summarise our theoretical and experimental results for solitons and Turing patterns in a system comprising a micro-resonator nested in an auxiliary fibre-gain cavity.

Optical-Pump Terahertz (THz) Near-Field Microscopy (OP-TNFM) is a novel technique for trans- carrier hyperspectral imaging, capable of extracting recombination dynamics and the spatially distributed complex refractive index that results from thermalised carriers in semiconducting materials.

In an open nonlinear system, emergent complex structures are generally determined by a set of global parameters. Cavity-solitons are an example of such structures and, in their temporal form, have seeded the last decade of major developments in microresonator-based optical frequency combs. These optical pulses typically require complex procedures and external feedback to be induced and maintained. Recent progress has seen the microresonators directly embedded into a laser cavity [1] , [2] where it is possible to simply initiate cavity-soliton formation by increasing the laser-diode driving current [3] . Hybrid laser-microresonator schemes have been considered since 2012 [4] , and extremely efficient laser cavity-solitons have been experimentally and theoretically demonstrated in a laser microcomb [5] .

We present a theoretical investigation of broadband, spatio-temporal control of THz light in random media. We consider the refocusing and compression of a THz pulse by optimising the spatiotemporal features of the transmitted field.

A cartographical study is conducted within the parameter space of a microresonator- filtered fiber laser. We identify a region in which solitons are spontaneously formed and maintained, and we investigate the effects which govern their emergence.

We provide the first demonstration of two-color optical rectification from semiconductors in an extreme absorption regime. The THz generation is free from phase-matching constraints due to the confinement of the interaction within a 25-atomic-layer region.

The stability of laser temporal cavity solitons in micro-ring cavities nested in an externally pumped fibre loop with gain is investigated. The crucial roles of group velocity mismatch and gain dispersion are identified.

Supplementary Material

We demonstrate a Terahertz Ghost-Imaging technique combining nonlinear pattern generation and single-pixel Time-Domain-Spectroscopy (TDS) detection. Our technique allows reconstructing the morphology and spectral features of subwavelength samples.

Terahertz (THz) spectroscopy systems are widely employed to retrieve the chemical and material composition of a sample. This is single-handed the most important driving motivation in the field and has largely contributed to shaping THz science as an independent subject. The limited availability of high-resolution imaging devices, however, still represents a major technological challenge in this promising field of research. In this theoretical work, we tackle this challenge by developing a novel nonlinear Ghost Imaging (GI) approach that conceptually outperforms established single-pixel imaging protocols at inaccessible wavelengths. Our methodology combines nonlinear THz generation with time-resolved field measurements, as enabled by state-of-the-art Time Domain Spectroscopy (TDS) techniques. As an ideal application target, we consider hyperspectral THz imaging of semi-transparent samples with nonnegligible delay contribution and we demonstrate how time-resolved, full-wave acquisition enables accurate spatiotemporal reconstruction of complex inhomogeneous samples.

We report the characterization of a balanced ultrafast photodetector. For this purpose, we use a recently developed time-domain laser-based vector network analyzer (VNA) to determine the common-mode rejection ratio (CMRR) of the device under test. This includes the frequency-domain response above the single-mode frequency of the coaxial connector. Although the balanced photodetector has a nominal bandwidth of 43 GHz, it generates voltage pulses with frequency components up to 180 GHz. We obtain a CMRR of better than 30 dB up to 70 GHz and better than 20 dB up to 110 GHz. The laser-based measurements are compared with the measurements using a digital sampling oscilloscope and with the frequency-domain measurements using a conventional VNA. We obtain good agreement between the three techniques with the laser-based method providing the largest measurement bandwidth, although it also constitutes the most complicated characterization setup.

Nanohybrid materials based on nanoparticles of the intrinsically microporous polymer PIM-1 and graphene oxide (GO) are prepared from aqueous dispersions with a re-precipitation method, resulting in the surface of the GO sheets being decorated with nanoparticles of PIM-1. The significant blueshift in fluorescence signals for the GO/PIM-1 nanohybrids indicates modification of the optoelectronic properties of the PIM-1 in the presence of the GO due to their strong interactions. The stiffening in the Raman G peak of GO (by nearly 6 cm^{-1}) further indicates p-doping of the GO in the presence of PIM. Kelvin probe force microscopy (KPFM) and electrochemical reduction measurements of the nanohybrids provide direct evidence for charge transfer between the PIM-1 nanoparticles and the GO nanosheets. These observations will be of importance for future applications of GO-PIM-1 nanohybrids as substrates and promoters in catalysis and sensing.

Modern optical systems increasingly rely on complex physical processes. Advanced light sources, such as supercontinuum (SC) [1], are highly sought for imaging and metrology, and are based on nonlinear dynamics where the output properties must often finely match target performance characteristics. However, in these systems, the availability of control parameters and the means to adjust them in a versatile manner are usually limited. Moreover, finding the ideal parameters for a specific application can become inherently complex. Here, we use an actively-controlled photonic chip to prepare and manipulate patterns of femtosecond optical pulses seeding supercontinuum generation [1]. Taking advantage of machine learning concepts [2], we exploit this access to an enhanced and tunable parameter space and experimentally demonstrate the customization of nonlinear interactions responsible for tailoring supercontinuum properties [3].

Plasmonic metasurfaces provide a compact platform to engineer the wave-front of optical beams by tuning the material and its morphology, hence enabling advanced functionalities in ultra-thin photonic systems [1,2]. In standard metasurfaces, however, the optical response is usually static and fixed by design. An appealing possibility to achieve ultrafast dynamical tuning is given by optically-induced plasmonic systems, where the metallic response of narrow-bandgap semiconductors is driven by high-fluence illumination. Under these conditions, the surface of the semiconductor can be overflown with photo-carriers inducing a transient metallic state [3]. An intriguing question is whether the transient metallization could be employed to dynamically engineer the optical response and to control light-matter interactions on the surface.

Micro-resonator-based frequency combs, or micro-combs, have gained considerable interest in recent years due to their many potential applications such as high-speed communication systems, spectroscopy and ultrafast optical clocks [1]. Most micro-combs systems are based on laser pumped optical parametric oscillation and are typically non-self-starting, requiring a well-defined warm-up strategy involving smart control [2]. An alternative approach to micro-combs is represented by the Filter-Driven Four-Wave Mixing (FD-FWM) laser [3–5], based on a nonlinear micro-resonator nested in a main amplifying fibre cavity. Although this system has demonstrated self-starting regimes, stable operation typically imposes a strict relation between the minimum free-spectral range (FSR) of the main-cavity and the Q-factor of the micro-resonator. The use of longer main-cavity fibre lengths (highly desirable for several positive features, such as a larger gain) results in unrecoverable unstable regimes, i.e. in super-mode instability, which arises from the existence of many oscillating main-cavity modes within each micro-resonator resonance.

One of the major challenges in photonics is the full-wave reconstruction of arbitrary field distributions. Indeed, measuring both the amplitude and the optical delay (or optical phase) entails achieving breakthroughs in a wide range of scenarios, spanning from bio-imaging to material characterisation [1]. Time-Domain Spectroscopy (TDS) is routinely employed to perform field-sensitive measurements at terahertz (THz) frequencies. THz has been widely employed in developing advanced spectroscopy applications, thanks to its non-ionizing nature and to the fact that several materials possess a distinctive THz signature. All these features allow to precisely determine the composition of complex samples with critical implications in several fields, such as in-vivo biological imaging, medical diagnosis, security scanners and manufacturing control [2–3]. Despite the large body of research, however, the limited availability of high-resolution, full-wave imaging devices (i.e. field-sensitive THz cameras) poses a critical technological limit in this promising field.

Nonlinear optics in sub-wavelength structures plays a crucial role in the development of integrated photonics platforms and devices [1]. Surfaces, nanostructures and two-dimensional media are inherently free from longitudinal phase matching constraints and constitute an attractive framework to engineer complex forms of lightmatter interactions [2–3]. Most recent efforts in this area have focused on the generation of frequencies in the optical and infrared regions, e.g., second or third harmonic generation. An open question, however, is whether the broadband frequency conversion enabled by nanoscale nonlinear media could lead to the generation of long-wavelength radiation in a process known as Optical Rectification (OR). To date, OR of ultrafast optical pulses in nonlinear media has been subject of intense research, since it provides a robust and versatile approach to generate and manipulate broadband Terahertz (THz) fields. Using non-centrosymmetric crystals such as ZnTe and LiNbO 3 , large bandwidth THz pulses limited mainly by longitudinal phase-matching constraints, could be achieved [4]. Highly nonlinear Quasi-2D structures represent an intriguing alternative to this popular approach.

We consider the passive modulation of the surface field at a junction between semiconductors and 2D-materials. We experimentally demonstrate that this boosts the optical-to-terahertz conversion efficiency beyond that of benchmark surface emitters.

Plasmonic metamaterials enable access to extremely nonlinear regimes with remarkable full-field control. We theoretically and experimentally demonstrate a novel form of photo-induced semiconducting Time-Dependent metamaterial at THz frequencies.

We demonstrate the first fully solid-state technique for the coherent detection of ultra-broadband THz pulses (0.1-10 THz), relying on the electric-field-induced second-harmonic generation attained in integrated CMOS-compatible devices.

Significant progress in nonlinear and ultrafast optics has recently opened new and exciting opportunities for terahertz (THz) science and technology, which require the development of reliable THz sources, detectors, and supporting devices. In this work, we demonstrate the first solid-state technique for the coherent detection of ultra-broadband THz pulses (0.1-10 THz), relying on the electric-field-induced second-harmonic generation in a thin layer of ultraviolet fused silica. The proposed CMOS-compatible devices, which can be realized with standard microfabrication techniques, allow us to perform ultra-broadband detection with a high dynamic range by employing probe laser powers and bias voltages much lower than those used in gas-based techniques. Eventually, this may pave the way for the use of high-repetition-rate ultrafast lasers and commercially available electronics for the coherent detection of ultrashort THz pulses.

Ring opening polymerization (ROP) of N-carboxy anhydride (NCA) amino acids presents a rapid way to synthesize high molecular weight polypeptides with different amino acid compositions. The compositional and functional versatility of polypeptides make these materials an attractive choice for biomaterials. The functional performance of polypeptide materials is equally linked to their conformation which is determined by the amino acid sequence in the polymer chains. Here, the interplay between composition and conformation of synthetic polypeptides obtained by NCA polymerization was explored. Various copolypeptides from Glu(Bzl) and Ser(Bzl) were prepared to investigate how polypeptide composition affected the conformation of the resulting copolymer. Polymerization kinetics indicated that the copolymerization of Glu(Bzl) and Ser(Bzl) preferentially yielded alternating copolymers. Both the polydispersity and the conformation of the polypeptides were dependent on the Ser(Bzl) content in the polymer, demonstrating that polypeptide functionalities could be tuned directly by altering the relative amounts of amino acids in the chain. This work presents the first step toward an improved understanding and control over polypeptide conformation through modulating the amino acid composition of the material. Understanding this sequence–functionality relationship is essential to advancing the use of ROP as a technique to design smart polypeptide based materials with specific functions. © 2016 The Authors. Journal of Polymer Science Part A: Polymer Chemistry Published by Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016, 54, 2331–2336

The FD-FWM is a proven approach to implement coherent Microcomb generation. Comb repetition rates can be finely controlled in a robust way, while maintaining the coherence during the whole process, whereas full-coherent type-I and type-II combs can be accessible. We present our recent advances towards effective control of optical combs exploiting integrated chip-based resonators.