@article{13346, abstract = {The self-assembly of nanoparticles driven by small molecules or ions may produce colloidal superlattices with features and properties reminiscent of those of metals or semiconductors. However, to what extent the properties of such supramolecular crystals actually resemble those of atomic materials often remains unclear. Here, we present coarse-grained molecular simulations explicitly demonstrating how a behavior evocative of that of semiconductors may emerge in a colloidal superlattice. As a case study, we focus on gold nanoparticles bearing positively charged groups that self-assemble into FCC crystals via mediation by citrate counterions. In silico ohmic experiments show how the dynamically diverse behavior of the ions in different superlattice domains allows the opening of conductive ionic gates above certain levels of applied electric fields. The observed binary conductive/nonconductive behavior is reminiscent of that of conventional semiconductors, while, at a supramolecular level, crossing the “band gap” requires a sufficient electrostatic stimulus to break the intermolecular interactions and make ions diffuse throughout the superlattice’s cavities.}, author = {Lionello, Chiara and Perego, Claudio and Gardin, Andrea and Klajn, Rafal and Pavan, Giovanni M.}, issn = {1936-086X}, journal = {ACS Nano}, keywords = {General Physics and Astronomy, General Engineering, General Materials Science}, number = {1}, pages = {275--287}, publisher = {American Chemical Society}, title = {{Supramolecular semiconductivity through emerging ionic gates in ion–nanoparticle superlattices}}, doi = {10.1021/acsnano.2c07558}, volume = {17}, year = {2023}, } @article{13354, abstract = {Integrating light-sensitive molecules within nanoparticle (NP) assemblies is an attractive approach to fabricate new photoresponsive nanomaterials. Here, we describe the concept of photocleavable anionic glue (PAG): small trianions capable of mediating interactions between (and inducing the aggregation of) cationic NPs by means of electrostatic interactions. Exposure to light converts PAGs into dianionic products incapable of maintaining the NPs in an assembled state, resulting in light-triggered disassembly of NP aggregates. To demonstrate the proof-of-concept, we work with an organic PAG incorporating the UV-cleavable o-nitrobenzyl moiety and an inorganic PAG, the photosensitive trioxalatocobaltate(III) complex, which absorbs light across the entire visible spectrum. Both PAGs were used to prepare either amorphous NP assemblies or regular superlattices with a long-range NP order. These NP aggregates disassembled rapidly upon light exposure for a specific time, which could be tuned by the incident light wavelength or the amount of PAG used. Selective excitation of the inorganic PAG in a system combining the two PAGs results in a photodecomposition product that deactivates the organic PAG, enabling nontrivial disassembly profiles under a single type of external stimulus.}, author = {Wang, Jinhua and Peled, Tzuf Shay and Klajn, Rafal}, issn = {1520-5126}, journal = {Journal of the American Chemical Society}, keywords = {Colloid and Surface Chemistry, Biochemistry, General Chemistry, Catalysis}, number = {7}, pages = {4098--4108}, publisher = {American Chemical Society}, title = {{Photocleavable anionic glues for light-responsive nanoparticle aggregates}}, doi = {10.1021/jacs.2c11973}, volume = {145}, year = {2023}, } @article{20966, abstract = {We prepared a series of water‐soluble aromatic oligoamide sequences all composed of a segment prone to form a single helix and a segment prone to dimerize into a double helix. These sequences exclusively assemble as antiparallel duplexes. The modification of the duplex inner rim by varying the nature of the substituents borne by the aromatic monomers allowed us to identify sequences that can hybridize by combining two chemically different strands, with high affinity and complete selectivity in water. X‐ray crystallography confirmed the expected antiparallel configuration of the duplexes whereas NMR spectroscopy and mass spectrometry allowed us to assess precisely the extent of the hybridization. The hybridization kinetics of the aromatic strands was shown to depend on both the nature of the substituents responsible for strand complementarity and the length of the aromatic strand. These results highlight the great potential of aromatic hetero‐duplex as a tool to construct non‐symmetrical dynamic supramolecular assemblies.}, author = {Koehler, Victor and Bruschera, Gabrielle and Merlet, Eric and Mandal, Pradeep K and Morvan, Estelle and Rosu, Frédéric and Douat, Céline and Fischer, Lucile and Huc, Ivan and Ferrand, Yann}, issn = {1521-3773}, journal = {Angewandte Chemie International Edition}, number = {48}, publisher = {Wiley}, title = {{High‐affinity hybridization of complementary aromatic oligoamide strands in water}}, doi = {10.1002/anie.202311639}, volume = {62}, year = {2023}, } @article{20968, abstract = {Several helically folded aromatic oligoamides were designed and synthesized. The sequences were all water-soluble thanks to the charged side chains borne by the monomers. Replacing a few, sometimes only two, charged side chains by neutral methoxy groups was shown to trigger the formation of various aggregates which could be tentatively assigned to head-to-head stacked dimers of single helices, double helical duplexes and a quadruplex, none of which would form in organic solvent with organic-soluble analogues. The nature of the aggregates was supported by concentration and solvent dependent NMR studies, 1H DOSY experiments, mass spectrometry, and X-ray crystallography or energy-minimized models, as well as analogies with earlier studies. The hydrophobic effect appears to be the main driving force for aggregation but it can be finely modulated by the presence or absence of a small number of charges to an extent that had no precedent in aromatic foldamer architectures. These results will serve as a benchmark for future foldamer design in water.}, author = {Teng, Binhao and Mandal, Pradeep K and Allmendinger, Lars and Douat, Céline and Ferrand, Yann and Huc, Ivan}, issn = {2041-6539}, journal = {Chemical Science}, number = {40}, pages = {11251--11260}, publisher = {Royal Society of Chemistry}, title = {{Controlling aromatic helix dimerization in water by tuning charge repulsions}}, doi = {10.1039/d3sc02020g}, volume = {14}, year = {2023}, } @article{20969, abstract = {The diastereoselective assembly of achiral constituents through a single spontaneous process into complex covalent architectures bearing multiple stereogenic elements still remains a challenge for synthetic chemists. Here, we show that such an extreme level of control can be achieved by implementing stereo-electronic information on synthetic organic building blocks and templates and that non-directional interactions (i.e., electrostatic and steric interactions) can transfer this information to deliver, after self-assembly, high-molecular weight macrocyclic species carrying up to 16 stereogenic elements. Beyond the field of supramolecular chemistry, this proof of concept should stimulate the on-demand production of highly structured polyfunctional architectures.}, author = {Zhang, Yuan and Ourri, Benjamin and Skowron, Pierre-Thomas and Jeamet, Emeric and Chetot, Titouan and Duchamp, Christian and Belenguer, Ana M. and Vanthuyne, Nicolas and Cala, Olivier and Dumont, Elise and Mandal, Pradeep K and Huc, Ivan and Perret, Florent and Vial, Laurent and Leclaire, Julien}, issn = {2041-6539}, journal = {Chemical Science}, number = {26}, pages = {7126--7135}, publisher = {Royal Society of Chemistry}, title = {{Self-assembly of achiral building blocks into chiral cyclophanes using non-directional interactions}}, doi = {10.1039/d3sc01235b}, volume = {14}, year = {2023}, } @article{20970, abstract = {Dynamic foldamers are synthetic folded molecules which can change their conformation in response to an external stimulus and are currently at the forefront of foldamer chemistry. However, constitutionally dynamic foldamers, which can change not only their conformation but also their molecular constitution in response to their environment, are without precedent. We now report a size- and shape-switching small dynamic covalent foldamer network which responds to changes in pH. Specifically, acidic conditions direct the oligomerization of a dipeptide-based building block into a 16-subunit macrocycle with well-defined conformation and with high selectivity. At higher pH the same building block yields another cyclic foldamer with a smaller ring size (9mer). The two foldamers readily and repeatedly interconvert upon adjustment of the pH of the solution. We have previously shown that addition of a template can direct oligomerization of the same building block to yet other rings sizes (including a 12mer and a 13mer, accompanied by a minor amount of 14mer). This brings the total number of discrete foldamers that can be accessed from a single building block to five. For a single building block system to exhibit such highly diverse structure space is unique and sets this system of foldamers apart from proteins. Furthermore, the emergence of constitutional dynamicity opens up new avenues to foldamers with adaptive behavior.}, author = {Jin, Yulong and Mandal, Pradeep K and Wu, Juntian and Böcher, Niklas and Huc, Ivan and Otto, Sijbren}, issn = {1520-5126}, journal = {Journal of the American Chemical Society}, number = {5}, pages = {2822--2829}, publisher = {American Chemical Society}, title = {{(Re-)directing oligomerization of a single building block into two specific dynamic covalent foldamers through pH}}, doi = {10.1021/jacs.2c09325}, volume = {145}, year = {2023}, } @article{21511, abstract = {Converting ionizing radiation into visible light is essential in a wide range of fundamental and industrial applications, such as electromagnetic calorimeters in high-energy particle detectors, electron detectors, image intensifiers, and X-ray imaging. These different areas of technology all rely on scintillators or phosphors, i.e., materials that emit light upon bombardment by high-energy particles. In all cases, the emission is through spontaneous emission. The fundamental nature of spontaneous emission poses limitations on all these technologies, imposing an intrinsic trade-off between efficiency and resolution in all imaging applications: thicker phosphors are more efficient due to their greater stopping power, which however comes at the expense of image blurring due to light spread inside the thicker phosphors. Here, the concept of inverse-designed nanophotonic scintillators is proposed, which can overcome the trade-off between resolution and efficiency by reshaping the intrinsic spontaneous emission. To exemplify the concept, multilayer phosphor nanostructures are designed and these nanostructures are compared to state-of-the-art phosphor screens in image intensifiers, showing a threefold resolution enhancement simultaneous with a threefold efficiency enhancement. The enabling concept is applying the ubiquitous Purcell effect for the first time in a new context—for improving image resolution. Looking forward, this approach directly applies to a wide range of technologies, including X-ray imaging applications.}, author = {Shultzman, Avner and Segal, Ohad and Kurman, Yaniv and Roques-Carmes, Charles and Kaminer, Ido}, issn = {2195-1071}, journal = {Advanced Optical Materials}, number = {8}, publisher = {Wiley}, title = {{Enhanced imaging using inverse design of nanophotonic scintillators}}, doi = {10.1002/adom.202202318}, volume = {11}, year = {2023}, } @article{21547, abstract = {Flatbands have become a cornerstone of contemporary condensed-matter physics and photonics. In electronics, flatbands entail comparable energy bandwidth and Coulomb interaction, leading to correlated phenomena such as the fractional quantum Hall effect and recently those in magic-angle systems. In photonics, they enable properties including slow light1 and lasing2. Notably, flatbands support supercollimation—diffractionless wavepacket propagation—in both systems3,4. Despite these intense parallel efforts, flatbands have never been shown to affect the core interaction between free electrons and photons. Their interaction, pivotal for free-electron lasers5, microscopy and spectroscopy6,7, and particle accelerators8,9, is, in fact, limited by a dimensionality mismatch between localized electrons and extended photons. Here we reveal theoretically that photonic flatbands can overcome this mismatch and thus remarkably boost their interaction. We design flatband resonances in a silicon-on-insulator photonic crystal slab to control and enhance the associated free-electron radiation by tuning their trajectory and velocity. We observe signatures of flatband enhancement, recording a two-order increase from the conventional diffraction-enabled Smith–Purcell radiation. The enhancement enables polarization shaping of free-electron radiation and characterization of photonic bands through electron-beam measurements. Our results support the use of flatbands as test beds for strong light–electron interaction, particularly relevant for efficient and compact free-electron light sources and accelerators.}, author = {Yang, Yi and Roques-Carmes, Charles and Kooi, Steven E. and Tang, Haoning and Beroz, Justin and Mazur, Eric and Kaminer, Ido and Joannopoulos, John D. and Soljačić, Marin}, issn = {1476-4687}, journal = {Nature}, pages = {42--47}, publisher = {Springer Nature}, title = {{Photonic flatband resonances for free-electron radiation}}, doi = {10.1038/s41586-022-05387-5}, volume = {613}, year = {2023}, } @article{21553, abstract = {When impinging on optical structures or passing in their vicinity, free electrons can spontaneously emit electromagnetic radiation, a phenomenon generally known as cathodoluminescence. Free-electron radiation comes in many guises: Cherenkov, transition, and Smith–Purcell radiation, but also electron scintillation, commonly referred to as incoherent cathodoluminescence. While those effects have been at the heart of many fundamental discoveries and technological developments in high-energy physics in the past century, their recent demonstration in photonic and nanophotonic systems has attracted a great deal of attention. Those developments arose from predictions that exploit nanophotonics for novel radiation regimes, now becoming accessible thanks to advances in nanofabrication. In general, the proper design of nanophotonic structures can enable shaping, control, and enhancement of free-electron radiation, for any of the above-mentioned effects. Free-electron radiation in nanophotonics opens the way to promising applications, such as widely tunable integrated light sources from x-ray to THz frequencies, miniaturized particle accelerators, and highly sensitive high-energy particle detectors. Here, we review the emerging field of free-electron radiation in nanophotonics. We first present a general, unified framework to describe free-electron light–matter interaction in arbitrary nanophotonic systems. We then show how this framework sheds light on the physical underpinnings of many methods in the field used to control and enhance free-electron radiation. Namely, the framework points to the central role played by the photonic eigenmodes in controlling the output properties of free-electron radiation (e.g., frequency, directionality, and polarization). We then review experimental techniques to characterize free-electron radiation in scanning and transmission electron microscopes, which have emerged as the central platforms for experimental realization of the phenomena described in this review. We further discuss various experimental methods to control and extract spectral, angular, and polarization-resolved information on free-electron radiation. We conclude this review by outlining novel directions for this field, including ultrafast and quantum effects in free-electron radiation, tunable short-wavelength emitters in the ultraviolet and soft x-ray regimes, and free-electron radiation from topological states in photonic crystals.}, author = {Roques-Carmes, Charles and Kooi, Steven E. and Yang, Yi and Rivera, Nicholas and Keathley, Phillip D. and Joannopoulos, John D. and Johnson, Steven G. and Kaminer, Ido and Berggren, Karl K. and Soljačić, Marin}, issn = {1931-9401}, journal = {Applied Physics Reviews}, number = {1}, publisher = {AIP Publishing}, title = {{Free-electron–light interactions in nanophotonics}}, doi = {10.1063/5.0118096}, volume = {10}, year = {2023}, } @article{21585, abstract = {Efficient learning algorithms are implemented in a silicon photonic neural network chip}, author = {Roques-Carmes, Charles}, issn = {1095-9203}, journal = {Science}, number = {6643}, pages = {341--342}, publisher = {American Association for the Advancement of Science}, title = {{Learning photons go backward}}, doi = {10.1126/science.adh0724}, volume = {380}, year = {2023}, } @article{21586, abstract = {Quantum field theory suggests that electromagnetic fields naturally fluctuate, and these fluctuations can be harnessed as a source of perfect randomness. Many potential applications of randomness rely on controllable probability distributions. We show that vacuum-level bias fields injected into multistable optical systems enable a controllable source of quantum randomness, and we demonstrated this concept in an optical parametric oscillator (OPO). By injecting bias pulses with less than one photon on average, we controlled the probabilities of the two possible OPO output states. The potential of our approach for sensing sub–photon-level fields was demonstrated by reconstructing the temporal shape of fields below the single-photon level. Our results provide a platform to study quantum dynamics in nonlinear driven-dissipative systems and point toward applications in probabilistic computing and weak field sensing.}, author = {Roques-Carmes, Charles and Salamin, Yannick and Sloan, Jamison and Choi, Seou and Velez, Gustavo and Koskas, Ethan and Rivera, Nicholas and Kooi, Steven E. and Joannopoulos, John D. and Soljačić, Marin}, issn = {1095-9203}, journal = {Science}, number = {6654}, pages = {205--209}, publisher = {American Association for the Advancement of Science}, title = {{Biasing the quantum vacuum to control macroscopic probability distributions}}, doi = {10.1126/science.adh4920}, volume = {381}, year = {2023}, } @inproceedings{21592, abstract = {We demonstrate improved X-ray imaging using nanophotonic scintillators. Our scintillators rely on Purcell enhancement for brighter and faster emission. Applying this concept in radiology and nuclear medicine could enable a significant reduction of X-ray dose.}, author = {Schuetz, Roman and Kurman, Yaniv and Lahav, Neta and Shultzman, Avner and Roques-Carmes, Charles and Lifshits, Alon and Zaken, Segev and Strassberg, Rotem and Be’er, Orr and Bekenstein, Yehonadav and Kaminer, Ido}, booktitle = {Conference on Lasers and Electro-Optics}, location = {San Jose, CA, United States}, publisher = {Optica Publishing Group}, title = {{Purcell-enhanced X-ray imaging in ultra-thin scintillators}}, doi = {10.1364/cleo_at.2023.aw3q.7}, year = {2023}, } @inproceedings{21595, abstract = {We present a method for x-ray spectroscopy, combining nanophotonic scintillator inverse design with an image reconstruction algorithm. We demonstrate our pipeline on 3-energy x-ray spectroscopy, achieving 8% reconstruction error under 1% Gaussian noise}, author = {Li, William F. and Roques-Carmes, Charles and Lin, Zin and Johnson, Steven G. and Soljačić, Marin}, booktitle = {Conference on Lasers and Electro-Optics}, location = {San Jose, CA, United States}, publisher = {Optica Publishing Group}, title = {{X-ray spectroscopy with end-to-end optimized nanophotonic scintillators}}, doi = {10.1364/cleo_fs.2023.fw4c.4}, year = {2023}, } @inproceedings{21629, abstract = {We measure the second-order coherence function g(2) for X-ray-driven light emission (scintillation), observing that it is bunched (g(2) > 1), and can achieve extreme bunching values (g(2)~97) in perovskite nano-crystals.}, author = {Katznelson, Shaul and Tziperman, Offek and Bucher, Tomer and Abudi, Tom Lenkiewicz and Schuetz, Roman and Be'er, Orr and Levy, Shai and Bekenstein, Yehonadav and Roques-Carmes, Charles and Kaminer, Ido}, booktitle = {Conference on Lasers and Electro-Optics}, location = {San Jose, CA, United States}, publisher = {Optica Publishing Group}, title = {{X-ray-driven photon bunching}}, doi = {10.1364/cleo_si.2023.sm1h.6}, year = {2023}, } @inproceedings{21630, abstract = {We demonstrate the generation of random bits with tunable probability distribution in an optical parametric oscillator. Bits are encoded into the phase statistics of the signal field, which are tuned by a small bias field.}, author = {Roques-Carmes, Charles and Salamin, Yannick and Sloan, Jamison and Velez, Gustavo and Koskas, Ethan and Choi, Seou and Rivera, Nicholas and Kooi, Steven E. and Joannopoulos, John and Soljačić, Marin}, booktitle = {Conference on Lasers and Electro-Optics}, location = {San Jose, CA, United States}, publisher = {Optica Publishing Group}, title = {{Tunable probabilities from the quantum vacuum}}, doi = {10.1364/cleo_si.2023.sth3f.3}, year = {2023}, } @inproceedings{21631, abstract = {We present inverse-designed multilayer nanophotonic scintillators with optimal efficiency, directionality, and point-spread function, for applications in x-ray imaging.}, author = {Shultzman, Avner and Segal, Ohad and Kurman, Yaniv and Roques-Carmes, Charles and Kaminer, Ido}, booktitle = {Conference on Lasers and Electro-Optics}, location = {San Jose, CA, United States}, publisher = {Optica Publishing Group}, title = {{Overcoming the imaging limits of high-energy particle detection via nanophotonic inverse-design}}, doi = {10.1364/cleo_si.2023.sth4g.8}, year = {2023}, } @article{21639, abstract = {Traditional optical elements and conventional metasurfaces obey shift-invariance in the paraxial regime. For imaging systems obeying paraxial shift-invariance, a small shift in input angle causes a corresponding shift in the sensor image. Shift-invariance has deep implications for the design and functionality of optical devices, such as the necessity of free space between components (as in compound objectives made of several curved surfaces). We present a method for nanophotonic inverse design of compact imaging systems whose resolution is not constrained by paraxial shift-invariance. Our method is end-to-end, in that it integrates density-based full-Maxwell topology optimization with a fully iterative elastic-net reconstruction algorithm. By the design of nanophotonic structures that scatter light in a non-shift-invariant manner, our optimized nanophotonic imaging system overcomes the limitations of paraxial shift-invariance, achieving accurate, noise-robust image reconstruction beyond shift-invariant resolution.}, author = {Li, William F. and Arya, Gaurav and Roques-Carmes, Charles and Lin, Zin and Johnson, Steven G. and Soljačić, Marin}, issn = {1094-4087}, journal = {Optics Express}, number = {15}, pages = {24260--24272}, publisher = {Optica Publishing Group}, title = {{Transcending shift-invariance in the paraxial regime via end-to-end inverse design of freeform nanophotonics}}, doi = {10.1364/oe.492553}, volume = {31}, year = {2023}, } @unpublished{21677, abstract = {Lasers with high intensity generally exhibit strong intensity fluctuations far above the shot-noise level. Taming this noise is pivotal to a wide range of applications, both classical and quantum. Here, we demonstrate the creation of intense light with quantum levels of noise even when starting from inputs with large amounts of excess noise. In particular, we demonstrate how intense squeezed light with intensities approaching 0.1 TW/cm^2, but noise at or below the shot noise level, can be produced from noisy inputs associated with high-power amplified laser sources (an overall noise-reduction of 30-fold). Based on a new theory of quantum noise in multimode systems, we show that the ability to generate quantum light from noisy inputs results from multimode quantum correlations, which maximally decouple the output light from the dominant noise channels in the input light. As an example, we demonstrate this effect for femtosecond pulses in nonlinear fibers, but the noise-immune correlations that enable our results are generic to many other nonlinear systems in optics and beyond.}, author = {Uddin, Shiekh Zia and Rivera, Nicholas and Seyler, Devin and Sloan, Jamison and Salamin, Yannick and Roques-Carmes, Charles and Xu, Shutao and Sander, Michelle and Kaminer, Ido and Soljacic, Marin}, booktitle = {arXiv}, title = {{Noise-immune quantum correlations of intense light}}, doi = {10.48550/arXiv.2311.05535}, year = {2023}, } @inbook{21739, abstract = {We revisit the derivation of the time-dependent Hartree–Fock equation for interacting fermions in a regime coupling a mean-field and a semiclassical scaling, contributing two comments to the result obtained in 2014 by Benedikter, Porta, and Schlein. First, the derivation holds in arbitrary space dimension. Second, by using an explicit formula for the unitary implementation of particle-hole transformations, we cast the proof in a form similar to the coherent state method of Rodnianski and Schlein for bosons.}, author = {Benedikter, Niels P and Desio, Davide}, booktitle = {Quantum Mathematics I}, editor = {Correggi, Michele and Falconi, Marco}, isbn = {9789819958931}, issn = {2281-5198}, pages = {319--333}, publisher = {Springer Nature}, title = {{Two Comments on the Derivation of the Time-Dependent Hartree–Fock Equation}}, doi = {10.1007/978-981-99-5894-8_13}, volume = {57}, year = {2023}, } @article{21807, abstract = {Multifaceted material responses upon exposure to stimuli are key for developing life-like materials. Developing such synthetic systems, though not trivial, typically relies on orthogonal stimuli to enable control of molecular systems that enable multi-responsive behavior. Access to complex tunable reaction mechanisms with diverse energy landscapes offers an alternative strategy for controlling out-of-equilibrium processes without requiring orthogonal stimuli for each responsive unit. Donor-acceptor Stenhouse adducts (DASAs) are a class of photoswitches that have complex, tunable, and environmentally sensitive reaction pathways. We present the control of donor-acceptor Stenhouse adduct equilibrium and photoswitching kinetics through changes in the polarity of their environment. Polarity and light can be used to selectively control the pathway outcomes of three DASA derivatives where the orthogonal response comes from changes in the energy landscape and is not driven by their orthogonal response to the given stimuli. This work paves the way to designing multi-responsive and self-regulating life-like materials.}, author = {Stricker, Friedrich J and Peterson, Julie and Sandlass, Sara K. and de Tagyos, Aurora and Sroda, Miranda and Seshadri, Serena and Gordon, Michael J. and Read de Alaniz, Javier}, issn = {2451-9294}, journal = {Chem}, number = {7}, pages = {1994--2005}, publisher = {Elsevier}, title = {{Selective control of donor-acceptor Stenhouse adduct populations with non-selective stimuli}}, doi = {10.1016/j.chempr.2023.05.011}, volume = {9}, year = {2023}, }