@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}, } @article{21810, abstract = {The next-generation semiconductors and devices, such as halide perovskites and flexible electronics, are extremely sensitive to water, thus demanding highly effective protection that not only seals out water in all forms (vapor, droplet, and ice), but simultaneously provides mechanical flexibility, durability, transparency, and self-cleaning. Although various solid-state encapsulation methods have been developed, no strategy is available that can fully meet all the above requirements. Here, we report a bioinspired liquid-based encapsulation strategy that offers protection from water without sacrificing the operational properties of the encapsulated materials. Using halide perovskite as a model system, we show that damage to the perovskite from exposure to water is drastically reduced when it is coated by a polymer matrix with infused hydrophobic oil. With a combination of experimental and simulation studies, we elucidated the fundamental transport mechanisms of ultralow water transmission rate that stem from the ability of the infused liquid to fill-in and reduce defects in the coating layer, thus eliminating the low-energy diffusion pathways, and to cause water molecules to diffuse as clusters, which act together as an excellent water permeation barrier. Importantly, the presence of the liquid, as the central component in this encapsulation method provides a unique possibility of reversing the water transport direction; therefore, the lifetime of enclosed water-sensitive materials could be significantly extended via replenishing the hydrophobic oils regularly. We show that the liquid encapsulation platform presented here has high potential in providing not only water protection of the functional device but also flexibility, optical transparency, and self-healing of the coating layer, which are critical for a variety of applications, such as in perovskite solar cells and bioelectronics.}, author = {Lemaire, Baptiste and Yu, Yanhao and Molinari, Nicola and Wu, Haichao and Goodwin, Zachary A. H. and Stricker, Friedrich J and Kozinsky, Boris and Aizenberg, Joanna}, issn = {1091-6490}, journal = {Proceedings of the National Academy of Sciences}, keywords = {water permeability, photoelectronic materials, device encapsulation, liquid-infused polymers}, number = {34}, publisher = {National Academy of Sciences}, title = {{Flexible fluid-based encapsulation platform for water-sensitive materials}}, doi = {10.1073/pnas.2308804120}, volume = {120}, year = {2023}, } @article{21813, abstract = {Aligned liquid crystal polymers are materials of interest for electronic, optic, biological and soft robotic applications. The manufacturing and processing of these materials have been widely explored with mechanical alignment establishing itself as a preferred method due to its ease of use and widespread applicability. However, the fundamental chemistry behind the required two‐step polymerization for mechanical alignment has limitations in both fabrication and substrate compatibility. In this work we introduce a new protection‐deprotection approach utilizing a two‐stage Diels–Alder cyclopentadiene‐maleimide step‐growth polymerization to enable mild yet efficient, fast, controlled, reproducible and user‐friendly polymerizations, broadening the scope of liquid crystal systems. Thorough characterization of the films by DSC, DMA, POM and WAXD show the successful synthesis of a uniaxially aligned liquid crystal network with thermomechanical actuation abilities.}, author = {Guillen Campos, Jesus and Stricker, Friedrich J and Clark, Kyle D. and Park, Minwook and Bailey, Sophia J. and Kuenstler, Alexa S. and Hayward, Ryan C. and Read de Alaniz, Javier}, issn = {1521-3773}, journal = {Angewandte Chemie International Edition}, number = {1}, publisher = {Wiley}, title = {{Controlled Diels–Alder “Click” strategy to access mechanically aligned main‐chain liquid crystal networks}}, doi = {10.1002/anie.202214339}, volume = {62}, year = {2023}, } @article{21818, abstract = {Surface-aligned liquid-crystal networks (LCNs) offer a solution for developing functional materials capable of performing a range of tasks, including actuation, shape memory, and surfaces patterning. Here we show that Diels–Alder cycloaddition can be used to prepare the backbone of planar aligned LCNs under mild ambient conditions without the addition of additives or UV irradiation. The mechanical properties of the networks have robust viscoelastic modulus and stiffness with a reversible local free volume change upon physical aging. This study shows new opportunities to design surface-aligned LCNs based on additive free step-growth Diels–Alder polymerization and enables the potential to incorporate a wider range of photochromic materials into LCNs.}, author = {Park, Minwook and Stricker, Friedrich J and Campos, Jesus Guillen and Clark, Kyle D. and Lee, Jaejun and Kwon, Younghoon and Valentine, Megan T. and Read de Alaniz, Javier}, issn = {2161-1653}, journal = {ACS Macro Letters}, number = {1}, pages = {33--39}, publisher = {American Chemical Society}, title = {{Design of surface-aligned main-chain liquid-crystal networks prepared under ambient, light-free conditions using the Diels–Alder cycloaddition}}, doi = {10.1021/acsmacrolett.2c00616}, volume = {12}, year = {2023}, } @article{21821, abstract = {Molecular photoswitches provide a means for imparting synthetic structures with intrinsically logical and highly tunable photoresponsive properties. One variety of organic photoswitches known as Donor-Acceptor Stenhouse Adducts, or DASAs, are promising candidates for next generation light responsive materials because of their unique ability to stabilize three photochemically distinct isomeric states in solution, while their counterparts are strictly limited to binary state behavior. In this work, we show how polymethacrylate host matrices shift the energetic landscape of DASA relative to solution, prohibiting accumulation of an intermediate third isomeric state by decelerating critical steps in the photoswitching mechanism. Specifically, we employ a dual-wavelength, phase locked detection scheme to probe thermal isomerizations in the switching process that occur at fast (~ms) time scales that are inaccessible by standard UV–Vis spectroscopic techniques. The results of this study provide valuable insight into the mechanism of multistate DASA reactivity and establish the foundation necessary to guide future efforts in offsetting kinetic matrix effects to enable dynamic, three state photoswitching in polymeric hosts. }, author = {Sandlass, Sara and Stricker, Friedrich J and Fragoso, Daniel and de Alaniz, Javier Read and Gordon, Michael J.}, issn = {1873-2666}, journal = {Journal of Photochemistry and Photobiology A: Chemistry}, publisher = {Elsevier}, title = {{Effect of polymer host matrix on multi-stage isomerization kinetics of DASA photochromes}}, doi = {10.1016/j.jphotochem.2023.114964}, volume = {444}, year = {2023}, } @unpublished{13447, abstract = {Asteroseismology has transformed stellar astrophysics. Red giant asteroseismology is a prime example, with oscillation periods and amplitudes that are readily detectable with time-domain space-based telescopes. These oscillations can be used to infer masses, ages and radii for large numbers of stars, providing unique constraints on stellar populations in our galaxy. The cadence, duration, and spatial resolution of the Roman galactic bulge time-domain survey (GBTDS) are well-suited for asteroseismology and will probe an important population not studied by prior missions. We identify photometric precision as a key requirement for realizing the potential of asteroseismology with Roman. A precision of 1 mmag per 15-min cadence or better for saturated stars will enable detections of the populous red clump star population in the Galactic bulge. If the survey efficiency is better than expected, we argue for repeat observations of the same fields to improve photometric precision, or covering additional fields to expand the stellar population reach if the photometric precision for saturated stars is better than 1 mmag. Asteroseismology is relatively insensitive to the timing of the observations during the mission, and the prime red clump targets can be observed in a single 70 day campaign in any given field. Complementary stellar characterization, particularly astrometry tied to the Gaia system, will also dramatically expand the diagnostic power of asteroseismology. We also highlight synergies to Roman GBTDS exoplanet science using transits and microlensing.}, author = {Huber, Daniel and Pinsonneault, Marc and Beck, Paul and Bedding, Timothy R. and Joss Bland-Hawthorn, Joss Bland-Hawthorn and Breton, Sylvain N. and Bugnet, Lisa Annabelle and Chaplin, William J. and Garcia, Rafael A. and Grunblatt, Samuel K. and Guzik, Joyce A. and Hekker, Saskia and Kawaler, Steven D. and Mathis, Stephane and Mathur, Savita and Metcalfe, Travis and Mosser, Benoit and Ness, Melissa K. and Piro, Anthony L. and Serenelli, Aldo and Sharma, Sanjib and Soderblom, David R. and Stassun, Keivan G. and Stello, Dennis and Tayar, Jamie and Belle, Gerard T. van and Zinn, Joel C.}, booktitle = {arXiv}, title = {{Asteroseismology with the Roman galactic bulge time-domain survey}}, doi = {10.48550/arXiv.2307.03237}, year = {2023}, } @article{13449, abstract = {Stars strongly impact their environment, and shape structures on all scales throughout the universe, in a process known as "feedback." Due to the complexity of both stellar evolution and the physics of larger astrophysical structures, there remain many unanswered questions about how feedback operates and what we can learn about stars by studying their imprint on the wider universe. In this white paper, we summarize discussions from the Lorentz Center meeting "Bringing Stellar Evolution and Feedback Together" in 2022 April and identify key areas where further dialog can bring about radical changes in how we view the relationship between stars and the universe they live in.}, author = {Geen, Sam and Agrawal, Poojan and Crowther, Paul A. and Keller, B. W. and de Koter, Alex and Keszthelyi, Zsolt and van de Voort, Freeke and Ali, Ahmad A. and Backs, Frank and Bonne, Lars and Brugaletta, Vittoria and Derkink, Annelotte and Ekström, Sylvia and Fichtner, Yvonne A. and Grassitelli, Luca and Götberg, Ylva Louise Linsdotter and Higgins, Erin R. and Laplace, Eva and You Liow, Kong and Lorenzo, Marta and McLeod, Anna F. and Meynet, Georges and Newsome, Megan and André Oliva, G. and Ramachandran, Varsha and Rey, Martin P. and Rieder, Steven and Romano-Díaz, Emilio and Sabhahit, Gautham and Sander, Andreas A. C. and Sarwar, Rafia and Stinshoff, Hanno and Stoop, Mitchel and Szécsi, Dorottya and Trebitsch, Maxime and Vink, Jorick S. and Winch, Ethan}, issn = {1538-3873}, journal = {Publications of the Astronomical Society of the Pacific}, keywords = {Space and Planetary Science, Astronomy and Astrophysics}, number = {1044}, publisher = {IOP Publishing}, title = {{Bringing stellar evolution and feedback together: Summary of proposals from the Lorentz Center workshop}}, doi = {10.1088/1538-3873/acb6b5}, volume = {135}, year = {2023}, } @article{13450, abstract = {In previous work, we identified a population of 38 cool and luminous variable stars in the Magellanic Clouds and examined 11 in detail in order to classify them as either Thorne–Żytkow objects (TŻOs; red supergiants with a neutron star cores) or super-asymptotic giant branch (sAGB) stars (the most massive stars that will not undergo core collapse). This population includes HV 2112, a peculiar star previously considered in other works to be either a TŻO or high-mass asymptotic giant branch (AGB) star. Here we continue this investigation, using the kinematic and radio environments and local star formation history of these stars to place constraints on the age of the progenitor systems and the presence of past supernovae. These stars are not associated with regions of recent star formation, and we find no evidence of past supernovae at their locations. Finally, we also assess the presence of heavy elements and lithium in their spectra compared to red supergiants. We find strong absorption in Li and s-process elements compared to RSGs in most of the sample, consistent with sAGB nucleosynthesis, while HV 2112 shows additional strong lines associated with TŻO nucleosynthesis. Coupled with our previous mass estimates, the results are consistent with the stars being massive (∼4–6.5 M⊙) or sAGB (∼6.5–12 M⊙) stars in the thermally pulsing phase, providing crucial observations of the transition between low- and high-mass stellar populations. HV 2112 is more ambiguous; it could either be a maximally massive sAGB star, or a TŻO if the minimum mass for stability extends down to ≲13 M⊙.}, author = {O‘Grady, Anna J. G. and Drout, Maria R. and Gaensler, B. M. and Kochanek, C. S. and Neugent, Kathryn F. and Doherty, Carolyn L. and Speagle, Joshua S. and Shappee, B. J. and Rauch, Michael and Götberg, Ylva Louise Linsdotter and Ludwig, Bethany and Thompson, Todd A.}, issn = {1538-4357}, journal = {The Astrophysical Journal}, keywords = {Space and Planetary Science, Astronomy and Astrophysics}, number = {1}, publisher = {American Astronomical Society}, title = {{Cool, luminous, and highly variable stars in the Magellanic Clouds. II. Spectroscopic and environmental analysis of Thorne–Żytkow object and super-AGB star candidates}}, doi = {10.3847/1538-4357/aca655}, volume = {943}, year = {2023}, } @article{13963, abstract = {The many-body localization (MBL) proximity effect is an intriguing phenomenon where a thermal bath localizes due to the interaction with a disordered system. The interplay of thermal and nonergodic behavior in these systems gives rise to a rich phase diagram, whose exploration is an active field of research. In this paper, we study a bosonic Hubbard model featuring two particle species representing the bath and the disordered system. Using state-of-the-art numerical techniques, we investigate the dynamics of the model in different regimes, based on which we obtain a tentative phase diagram as a function of coupling strength and bath size. When the bath is composed of a single particle, we observe clear signatures of a transition from an MBL proximity effect to a delocalized phase. Increasing the bath size, however, its thermalizing effect becomes stronger and eventually the whole system delocalizes in the range of moderate interaction strengths studied. In this regime, we characterize particle transport, revealing diffusive behavior of the originally localized bosons.}, author = {Brighi, Pietro and Ljubotina, Marko and Abanin, Dmitry A. and Serbyn, Maksym}, issn = {2469-9969}, journal = {Physical Review B}, number = {5}, publisher = {American Physical Society}, title = {{Many-body localization proximity effect in a two-species bosonic Hubbard model}}, doi = {10.1103/physrevb.108.054201}, volume = {108}, year = {2023}, } @article{13966, abstract = {We present a low-scaling diagrammatic Monte Carlo approach to molecular correlation energies. Using combinatorial graph theory to encode many-body Hugenholtz diagrams, we sample the Møller-Plesset (MPn) perturbation series, obtaining accurate correlation energies up to n=5, with quadratic scaling in the number of basis functions. Our technique reduces the computational complexity of the molecular many-fermion correlation problem, opening up the possibility of low-scaling, accurate stochastic computations for a wide class of many-body systems described by Hugenholtz diagrams.}, author = {Bighin, Giacomo and Ho, Quoc P and Lemeshko, Mikhail and Tscherbul, T. V.}, issn = {2469-9969}, journal = {Physical Review B}, number = {4}, publisher = {American Physical Society}, title = {{Diagrammatic Monte Carlo for electronic correlation in molecules: High-order many-body perturbation theory with low scaling}}, doi = {10.1103/PhysRevB.108.045115}, volume = {108}, year = {2023}, } @article{13969, abstract = {Bundling crossings is a strategy which can enhance the readability of graph drawings. In this paper we consider good drawings, i.e., we require that any two edges have at most one common point which can be a common vertex or a crossing. Our main result is that there is a polynomial-time algorithm to compute an 8-approximation of the bundled crossing number of a good drawing with no toothed hole. In general the number of toothed holes has to be added to the 8-approximation. In the special case of circular drawings the approximation factor is 8, this improves upon the 10-approximation of Fink et al. [14]. Our approach also works with the same approximation factor for families of pseudosegments, i.e., curves intersecting at most once. We also show how to compute a 9/2-approximation when the intersection graph of the pseudosegments is bipartite and has no toothed hole.}, author = {Arroyo Guevara, Alan M and Felsner, Stefan}, issn = {1526-1719}, journal = {Journal of Graph Algorithms and Applications}, number = {6}, pages = {433--457}, publisher = {Brown University}, title = {{Approximating the bundled crossing number}}, doi = {10.7155/jgaa.00629}, volume = {27}, year = {2023}, }