@article{9048,
abstract = {The analogy between an equilibrium partition function and the return probability in many-body unitary dynamics has led to the concept of dynamical quantum phase transition (DQPT). DQPTs are defined by nonanalyticities in the return amplitude and are present in many models. In some cases, DQPTs can be related to equilibrium concepts, such as order parameters, yet their universal description is an open question. In this Letter, we provide first steps toward a classification of DQPTs by using a matrix product state description of unitary dynamics in the thermodynamic limit. This allows us to distinguish the two limiting cases of “precession” and “entanglement” DQPTs, which are illustrated using an analytical description in the quantum Ising model. While precession DQPTs are characterized by a large entanglement gap and are semiclassical in their nature, entanglement DQPTs occur near avoided crossings in the entanglement spectrum and can be distinguished by a complex pattern of nonlocal correlations. We demonstrate the existence of precession and entanglement DQPTs beyond Ising models, discuss observables that can distinguish them, and relate their interplay to complex DQPT phenomenology.},
author = {De Nicola, Stefano and Michailidis, Alexios and Serbyn, Maksym},
issn = {1079-7114},
journal = {Physical Review Letters},
keywords = {General Physics and Astronomy},
number = {4},
publisher = {American Physical Society},
title = {{Entanglement view of dynamical quantum phase transitions}},
doi = {10.1103/physrevlett.126.040602},
volume = {126},
year = {2021},
}
@article{9235,
abstract = {Cu2–xS has become one of the most promising thermoelectric materials for application in the middle-high temperature range. Its advantages include the abundance, low cost, and safety of its elements and a high performance at relatively elevated temperatures. However, stability issues limit its operation current and temperature, thus calling for the optimization of the material performance in the middle temperature range. Here, we present a synthetic protocol for large scale production of covellite CuS nanoparticles at ambient temperature and atmosphere, and using water as a solvent. The crystal phase and stoichiometry of the particles are afterward tuned through an annealing process at a moderate temperature under inert or reducing atmosphere. While annealing under argon results in Cu1.8S nanopowder with a rhombohedral crystal phase, annealing in an atmosphere containing hydrogen leads to tetragonal Cu1.96S. High temperature X-ray diffraction analysis shows the material annealed in argon to transform to the cubic phase at ca. 400 K, while the material annealed in the presence of hydrogen undergoes two phase transitions, first to hexagonal and then to the cubic structure. The annealing atmosphere, temperature, and time allow adjustment of the density of copper vacancies and thus tuning of the charge carrier concentration and material transport properties. In this direction, the material annealed under Ar is characterized by higher electrical conductivities but lower Seebeck coefficients than the material annealed in the presence of hydrogen. By optimizing the charge carrier concentration through the annealing time, Cu2–xS with record figures of merit in the middle temperature range, up to 1.41 at 710 K, is obtained. We finally demonstrate that this strategy, based on a low-cost and scalable solution synthesis process, is also suitable for the production of high performance Cu2–xS layers using high throughput and cost-effective printing technologies.},
author = {Li, Mengyao and Liu, Yu and Zhang, Yu and Han, Xu and Zhang, Ting and Zuo, Yong and Xie, Chenyang and Xiao, Ke and Arbiol, Jordi and Llorca, Jordi and Ibáñez, Maria and Liu, Junfeng and Cabot, Andreu},
issn = {1936-086X},
journal = {ACS Nano},
keywords = {General Engineering, General Physics and Astronomy, General Materials Science},
number = {3},
pages = {4967–4978},
publisher = {American Chemical Society },
title = {{Effect of the annealing atmosphere on crystal phase and thermoelectric properties of copper sulfide}},
doi = {10.1021/acsnano.0c09866},
volume = {15},
year = {2021},
}
@article{9431,
abstract = {Inositol hexakisphosphate (IP6) is an assembly cofactor for HIV-1. We report here that IP6 is also used for assembly of Rous sarcoma virus (RSV), a retrovirus from a different genus. IP6 is ~100-fold more potent at promoting RSV mature capsid protein (CA) assembly than observed for HIV-1 and removal of IP6 in cells reduces infectivity by 100-fold. Here, visualized by cryo-electron tomography and subtomogram averaging, mature capsid-like particles show an IP6-like density in the CA hexamer, coordinated by rings of six lysines and six arginines. Phosphate and IP6 have opposing effects on CA in vitro assembly, inducing formation of T = 1 icosahedrons and tubes, respectively, implying that phosphate promotes pentamer and IP6 hexamer formation. Subtomogram averaging and classification optimized for analysis of pleomorphic retrovirus particles reveal that the heterogeneity of mature RSV CA polyhedrons results from an unexpected, intrinsic CA hexamer flexibility. In contrast, the CA pentamer forms rigid units organizing the local architecture. These different features of hexamers and pentamers determine the structural mechanism to form CA polyhedrons of variable shape in mature RSV particles.},
author = {Obr, Martin and Ricana, Clifton L. and Nikulin, Nadia and Feathers, Jon-Philip R. and Klanschnig, Marco and Thader, Andreas and Johnson, Marc C. and Vogt, Volker M. and Schur, Florian KM and Dick, Robert A.},
issn = {2041-1723},
journal = {Nature Communications},
keywords = {General Biochemistry, Genetics and Molecular Biology, General Physics and Astronomy, General Chemistry},
number = {1},
publisher = {Nature Research},
title = {{Structure of the mature Rous sarcoma virus lattice reveals a role for IP6 in the formation of the capsid hexamer}},
doi = {10.1038/s41467-021-23506-0},
volume = {12},
year = {2021},
}
@article{9540,
abstract = {The hexameric AAA-ATPase Drg1 is a key factor in eukaryotic ribosome biogenesis and initiates cytoplasmic maturation of the large ribosomal subunit by releasing the shuttling maturation factor Rlp24. Drg1 monomers contain two AAA-domains (D1 and D2) that act in a concerted manner. Rlp24 release is inhibited by the drug diazaborine which blocks ATP hydrolysis in D2. The mode of inhibition was unknown. Here we show the first cryo-EM structure of Drg1 revealing the inhibitory mechanism. Diazaborine forms a covalent bond to the 2′-OH of the nucleotide in D2, explaining its specificity for this site. As a consequence, the D2 domain is locked in a rigid, inactive state, stalling the whole Drg1 hexamer. Resistance mechanisms identified include abolished drug binding and altered positioning of the nucleotide. Our results suggest nucleotide-modifying compounds as potential novel inhibitors for AAA-ATPases.},
author = {Prattes, Michael and Grishkovskaya, Irina and Hodirnau, Victor-Valentin and Rössler, Ingrid and Klein, Isabella and Hetzmannseder, Christina and Zisser, Gertrude and Gruber, Christian C. and Gruber, Karl and Haselbach, David and Bergler, Helmut},
issn = {2041-1723},
journal = {Nature Communications},
keywords = {General Biochemistry, Genetics and Molecular Biology, General Physics and Astronomy, General Chemistry},
number = {1},
publisher = {Springer Nature},
title = {{Structural basis for inhibition of the AAA-ATPase Drg1 by diazaborine}},
doi = {10.1038/s41467-021-23854-x},
volume = {12},
year = {2021},
}
@article{9778,
abstract = {The hippocampal mossy fiber synapse is a key synapse of the trisynaptic circuit. Post-tetanic potentiation (PTP) is the most powerful form of plasticity at this synaptic connection. It is widely believed that mossy fiber PTP is an entirely presynaptic phenomenon, implying that PTP induction is input-specific, and requires neither activity of multiple inputs nor stimulation of postsynaptic neurons. To directly test cooperativity and associativity, we made paired recordings between single mossy fiber terminals and postsynaptic CA3 pyramidal neurons in rat brain slices. By stimulating non-overlapping mossy fiber inputs converging onto single CA3 neurons, we confirm that PTP is input-specific and non-cooperative. Unexpectedly, mossy fiber PTP exhibits anti-associative induction properties. EPSCs show only minimal PTP after combined pre- and postsynaptic high-frequency stimulation with intact postsynaptic Ca2+ signaling, but marked PTP in the absence of postsynaptic spiking and after suppression of postsynaptic Ca2+ signaling (10 mM EGTA). PTP is largely recovered by inhibitors of voltage-gated R- and L-type Ca2+ channels, group II mGluRs, and vacuolar-type H+-ATPase, suggesting the involvement of retrograde vesicular glutamate signaling. Transsynaptic regulation of PTP extends the repertoire of synaptic computations, implementing a brake on mossy fiber detonation and a “smart teacher” function of hippocampal mossy fiber synapses.},
author = {Vandael, David H and Okamoto, Yuji and Jonas, Peter M},
issn = {2041-1723},
journal = {Nature Communications},
keywords = {general physics and astronomy, general biochemistry, genetics and molecular biology, general chemistry},
number = {1},
publisher = {Springer},
title = {{Transsynaptic modulation of presynaptic short-term plasticity in hippocampal mossy fiber synapses}},
doi = {10.1038/s41467-021-23153-5},
volume = {12},
year = {2021},
}
@article{9981,
abstract = {The numerical simulation of dynamical phenomena in interacting quantum systems is a notoriously hard problem. Although a number of promising numerical methods exist, they often have limited applicability due to the growth of entanglement or the presence of the so-called sign problem. In this work, we develop an importance sampling scheme for the simulation of quantum spin dynamics, building on a recent approach mapping quantum spin systems to classical stochastic processes. The importance sampling scheme is based on identifying the classical trajectory that yields the largest contribution to a given quantum observable. An exact transformation is then carried out to preferentially sample trajectories that are close to the dominant one. We demonstrate that this approach is capable of reducing the temporal growth of fluctuations in the stochastic quantities, thus extending the range of accessible times and system sizes compared to direct sampling. We discuss advantages and limitations of the proposed approach, outlining directions
for further developments.},
author = {De Nicola, Stefano},
issn = {2666-9366},
journal = {SciPost Physics},
keywords = {General Physics and Astronomy},
number = {3},
publisher = {SciPost Foundation},
title = {{Importance sampling scheme for the stochastic simulation of quantum spin dynamics}},
doi = {10.21468/scipostphys.11.3.048},
volume = {11},
year = {2021},
}
@article{13999,
abstract = {Attosecond chronoscopy has revealed small but measurable delays in photoionization, characterized by the ejection of an electron on absorption of a single photon. Ionization-delay measurements in atomic targets provide a wealth of information about the timing of the photoelectric effect, resonances, electron correlations and transport. However, extending this approach to molecules presents challenges, such as identifying the correct ionization channels and the effect of the anisotropic molecular landscape on the measured delays. Here, we measure ionization delays from ethyl iodide around a giant dipole resonance. By using the theoretical value for the iodine atom as a reference, we disentangle the contribution from the functional ethyl group, which is responsible for the characteristic chemical reactivity of a molecule. We find a substantial additional delay caused by the presence of a functional group, which encodes the effect of the molecular potential on the departing electron. Such information is inaccessible to the conventional approach of measuring photoionization cross-sections. The results establish ionization-delay measurements as a valuable tool in investigating the electronic properties of molecules.},
author = {Biswas, Shubhadeep and Förg, Benjamin and Ortmann, Lisa and Schötz, Johannes and Schweinberger, Wolfgang and Zimmermann, Tomáš and Pi, Liangwen and Baykusheva, Denitsa Rangelova and Masood, Hafiz A. and Liontos, Ioannis and Kamal, Amgad M. and Kling, Nora G. and Alharbi, Abdullah F. and Alharbi, Meshaal and Azzeer, Abdallah M. and Hartmann, Gregor and Wörner, Hans J. and Landsman, Alexandra S. and Kling, Matthias F.},
issn = {1745-2481},
journal = {Nature Physics},
keywords = {General Physics and Astronomy},
number = {7},
pages = {778--783},
publisher = {Springer Nature},
title = {{Probing molecular environment through photoemission delays}},
doi = {10.1038/s41567-020-0887-8},
volume = {16},
year = {2020},
}
@article{15142,
abstract = {Bacteria and archaea employ CRISPR (clustered, regularly, interspaced, short palindromic repeats)-Cas (CRISPR-associated) systems as a type of adaptive immunity to target and degrade foreign nucleic acids. While a myriad of CRISPR-Cas systems have been identified to date, type I-C is one of the most commonly found subtypes in nature. Interestingly, the type I-C system employs a minimal Cascade effector complex, which encodes only three unique subunits in its operon. Here, we present a 3.1 Å resolution cryo-EM structure of the Desulfovibrio vulgaris type I-C Cascade, revealing the molecular mechanisms that underlie RNA-directed complex assembly. We demonstrate how this minimal Cascade utilizes previously overlooked, non-canonical small subunits to stabilize R-loop formation. Furthermore, we describe putative PAM and Cas3 binding sites. These findings provide the structural basis for harnessing the type I-C Cascade as a genome-engineering tool.},
author = {O’Brien, Roisin E. and Santos, Inês C. and Wrapp, Daniel and Bravo, Jack Peter Kelly and Schwartz, Evan A. and Brodbelt, Jennifer S. and Taylor, David W.},
issn = {2041-1723},
journal = {Nature Communications},
keywords = {General Physics and Astronomy, General Biochemistry, Genetics and Molecular Biology, General Chemistry, Multidisciplinary},
publisher = {Springer Nature},
title = {{Structural basis for assembly of non-canonical small subunits into type I-C Cascade}},
doi = {10.1038/s41467-020-19785-8},
volume = {11},
year = {2020},
}
@article{10353,
abstract = {Experiments have suggested that bacterial mechanosensitive channels separate into 2D clusters, the role of which is unclear. By developing a coarse-grained computer model we find that clustering promotes the channel closure, which is highly dependent on the channel concentration and membrane stress. This behaviour yields a tightly regulated gating system, whereby at high tensions channels gate individually, and at lower tensions the channels spontaneously aggregate and inactivate. We implement this positive feedback into the model for cell volume regulation, and find that the channel clustering protects the cell against excessive loss of cytoplasmic content.},
author = {Paraschiv, Alexandru and Hegde, Smitha and Ganti, Raman and Pilizota, Teuta and Šarić, Anđela},
issn = {1079-7114},
journal = {Physical Review Letters},
keywords = {general physics and astronomy},
number = {4},
publisher = {American Physical Society},
title = {{Dynamic clustering regulates activity of mechanosensitive membrane channels}},
doi = {10.1103/physrevlett.124.048102},
volume = {124},
year = {2020},
}
@article{8568,
abstract = {Aqueous iodine based electrochemical energy storage is considered a potential candidate to improve sustainability and performance of current battery and supercapacitor technology. It harnesses the redox activity of iodide, iodine, and polyiodide species in the confined geometry of nanoporous carbon electrodes. However, current descriptions of the electrochemical reaction mechanism to interconvert these species are elusive. Here we show that electrochemical oxidation of iodide in nanoporous carbons forms persistent solid iodine deposits. Confinement slows down dissolution into triiodide and pentaiodide, responsible for otherwise significant self-discharge via shuttling. The main tools for these insights are in situ Raman spectroscopy and in situ small and wide-angle X-ray scattering (in situ SAXS/WAXS). In situ Raman confirms the reversible formation of triiodide and pentaiodide. In situ SAXS/WAXS indicates remarkable amounts of solid iodine deposited in the carbon nanopores. Combined with stochastic modeling, in situ SAXS allows quantifying the solid iodine volume fraction and visualizing the iodine structure on 3D lattice models at the sub-nanometer scale. Based on the derived mechanism, we demonstrate strategies for improved iodine pore filling capacity and prevention of self-discharge, applicable to hybrid supercapacitors and batteries.},
author = {Prehal, Christian and Fitzek, Harald and Kothleitner, Gerald and Presser, Volker and Gollas, Bernhard and Freunberger, Stefan Alexander and Abbas, Qamar},
issn = {2041-1723},
journal = {Nature Communications},
keywords = {General Biochemistry, Genetics and Molecular Biology, General Physics and Astronomy, General Chemistry},
publisher = {Springer Nature},
title = {{Persistent and reversible solid iodine electrodeposition in nanoporous carbons}},
doi = {10.1038/s41467-020-18610-6},
volume = {11},
year = {2020},
}
@article{8592,
abstract = {Glioblastoma is the most malignant cancer in the brain and currently incurable. It is urgent to identify effective targets for this lethal disease. Inhibition of such targets should suppress the growth of cancer cells and, ideally also precancerous cells for early prevention, but minimally affect their normal counterparts. Using genetic mouse models with neural stem cells (NSCs) or oligodendrocyte precursor cells (OPCs) as the cells‐of‐origin/mutation, it is shown that the susceptibility of cells within the development hierarchy of glioma to the knockout of insulin‐like growth factor I receptor (IGF1R) is determined not only by their oncogenic states, but also by their cell identities/states. Knockout of IGF1R selectively disrupts the growth of mutant and transformed, but not normal OPCs, or NSCs. The desirable outcome of IGF1R knockout on cell growth requires the mutant cells to commit to the OPC identity regardless of its development hierarchical status. At the molecular level, oncogenic mutations reprogram the cellular network of OPCs and force them to depend more on IGF1R for their growth. A new‐generation brain‐penetrable, orally available IGF1R inhibitor harnessing tumor OPCs in the brain is also developed. The findings reveal the cellular window of IGF1R targeting and establish IGF1R as an effective target for the prevention and treatment of glioblastoma.},
author = {Tian, Anhao and Kang, Bo and Li, Baizhou and Qiu, Biying and Jiang, Wenhong and Shao, Fangjie and Gao, Qingqing and Liu, Rui and Cai, Chengwei and Jing, Rui and Wang, Wei and Chen, Pengxiang and Liang, Qinghui and Bao, Lili and Man, Jianghong and Wang, Yan and Shi, Yu and Li, Jin and Yang, Minmin and Wang, Lisha and Zhang, Jianmin and Hippenmeyer, Simon and Zhu, Junming and Bian, Xiuwu and Wang, Ying‐Jie and Liu, Chong},
issn = {2198-3844},
journal = {Advanced Science},
keywords = {General Engineering, General Physics and Astronomy, General Materials Science, Medicine (miscellaneous), General Chemical Engineering, Biochemistry, Genetics and Molecular Biology (miscellaneous)},
number = {21},
publisher = {Wiley},
title = {{Oncogenic state and cell identity combinatorially dictate the susceptibility of cells within glioma development hierarchy to IGF1R targeting}},
doi = {10.1002/advs.202001724},
volume = {7},
year = {2020},
}
@article{8634,
abstract = {In laboratory studies and numerical simulations, we observe clear signatures of unstable time-periodic solutions in a moderately turbulent quasi-two-dimensional flow. We validate the dynamical relevance of such solutions by demonstrating that turbulent flows in both experiment and numerics transiently display time-periodic dynamics when they shadow unstable periodic orbits (UPOs). We show that UPOs we computed are also statistically significant, with turbulent flows spending a sizable fraction of the total time near these solutions. As a result, the average rates of energy input and dissipation for the turbulent flow and frequently visited UPOs differ only by a few percent.},
author = {Suri, Balachandra and Kageorge, Logan and Grigoriev, Roman O. and Schatz, Michael F.},
issn = {1079-7114},
journal = {Physical Review Letters},
keywords = {General Physics and Astronomy},
number = {6},
publisher = {American Physical Society},
title = {{Capturing turbulent dynamics and statistics in experiments with unstable periodic orbits}},
doi = {10.1103/physrevlett.125.064501},
volume = {125},
year = {2020},
}
@article{8744,
abstract = {Understanding the conformational sampling of translation-arrested ribosome nascent chain complexes is key to understand co-translational folding. Up to now, coupling of cysteine oxidation, disulfide bond formation and structure formation in nascent chains has remained elusive. Here, we investigate the eye-lens protein γB-crystallin in the ribosomal exit tunnel. Using mass spectrometry, theoretical simulations, dynamic nuclear polarization-enhanced solid-state nuclear magnetic resonance and cryo-electron microscopy, we show that thiol groups of cysteine residues undergo S-glutathionylation and S-nitrosylation and form non-native disulfide bonds. Thus, covalent modification chemistry occurs already prior to nascent chain release as the ribosome exit tunnel provides sufficient space even for disulfide bond formation which can guide protein folding.},
author = {Schulte, Linda and Mao, Jiafei and Reitz, Julian and Sreeramulu, Sridhar and Kudlinzki, Denis and Hodirnau, Victor-Valentin and Meier-Credo, Jakob and Saxena, Krishna and Buhr, Florian and Langer, Julian D. and Blackledge, Martin and Frangakis, Achilleas S. and Glaubitz, Clemens and Schwalbe, Harald},
issn = {2041-1723},
journal = {Nature Communications},
keywords = {General Biochemistry, Genetics and Molecular Biology, General Physics and Astronomy, General Chemistry},
publisher = {Springer Nature},
title = {{Cysteine oxidation and disulfide formation in the ribosomal exit tunnel}},
doi = {10.1038/s41467-020-19372-x},
volume = {11},
year = {2020},
}
@article{8971,
abstract = {The actin-related protein (Arp)2/3 complex nucleates branched actin filament networks pivotal for cell migration, endocytosis and pathogen infection. Its activation is tightly regulated and involves complex structural rearrangements and actin filament binding, which are yet to be understood. Here, we report a 9.0 Å resolution structure of the actin filament Arp2/3 complex branch junction in cells using cryo-electron tomography and subtomogram averaging. This allows us to generate an accurate model of the active Arp2/3 complex in the branch junction and its interaction with actin filaments. Notably, our model reveals a previously undescribed set of interactions of the Arp2/3 complex with the mother filament, significantly different to the previous branch junction model. Our structure also indicates a central role for the ArpC3 subunit in stabilizing the active conformation.},
author = {Fäßler, Florian and Dimchev, Georgi A and Hodirnau, Victor-Valentin and Wan, William and Schur, Florian KM},
issn = {2041-1723},
journal = {Nature Communications},
keywords = {General Biochemistry, Genetics and Molecular Biology, General Physics and Astronomy, General Chemistry},
publisher = {Springer Nature},
title = {{Cryo-electron tomography structure of Arp2/3 complex in cells reveals new insights into the branch junction}},
doi = {10.1038/s41467-020-20286-x},
volume = {11},
year = {2020},
}
@article{9164,
author = {Speck, Thomas and Tailleur, Julien and Palacci, Jérémie A},
issn = {1367-2630},
journal = {New Journal of Physics},
keywords = {General Physics and Astronomy},
number = {6},
publisher = {IOP Publishing},
title = {{Focus on active colloids and nanoparticles}},
doi = {10.1088/1367-2630/ab90d9},
volume = {22},
year = {2020},
}
@article{8587,
abstract = {Inspired by the possibility to experimentally manipulate and enhance chemical reactivity in helium nanodroplets, we investigate the effective interaction and the resulting correlations between two diatomic molecules immersed in a bath of bosons. By analogy with the bipolaron, we introduce the biangulon quasiparticle describing two rotating molecules that align with respect to each other due to the effective attractive interaction mediated by the excitations of the bath. We study this system in different parameter regimes and apply several theoretical approaches to describe its properties. Using a Born–Oppenheimer approximation, we investigate the dependence of the effective intermolecular interaction on the rotational state of the two molecules. In the strong-coupling regime, a product-state ansatz shows that the molecules tend to have a strong alignment in the ground state. To investigate the system in the weak-coupling regime, we apply a one-phonon excitation variational ansatz, which allows us to access the energy spectrum. In comparison to the angulon quasiparticle, the biangulon shows shifted angulon instabilities and an additional spectral instability, where resonant angular momentum transfer between the molecules and the bath takes place. These features are proposed as an experimentally observable signature for the formation of the biangulon quasiparticle. Finally, by using products of single angulon and bare impurity wave functions as basis states, we introduce a diagonalization scheme that allows us to describe the transition from two separated angulons to a biangulon as a function of the distance between the two molecules.},
author = {Li, Xiang and Yakaboylu, Enderalp and Bighin, Giacomo and Schmidt, Richard and Lemeshko, Mikhail and Deuchert, Andreas},
issn = {1089-7690},
journal = {The Journal of Chemical Physics},
keywords = {Physical and Theoretical Chemistry, General Physics and Astronomy},
number = {16},
publisher = {AIP Publishing},
title = {{Intermolecular forces and correlations mediated by a phonon bath}},
doi = {10.1063/1.5144759},
volume = {152},
year = {2020},
}
@article{8529,
abstract = {Practical quantum networks require low-loss and noise-resilient optical interconnects as well as non-Gaussian resources for entanglement distillation and distributed quantum computation. The latter could be provided by superconducting circuits but existing solutions to interface the microwave and optical domains lack either scalability or efficiency, and in most cases the conversion noise is not known. In this work we utilize the unique opportunities of silicon photonics, cavity optomechanics and superconducting circuits to demonstrate a fully integrated, coherent transducer interfacing the microwave X and the telecom S bands with a total (internal) bidirectional transduction efficiency of 1.2% (135%) at millikelvin temperatures. The coupling relies solely on the radiation pressure interaction mediated by the femtometer-scale motion of two silicon nanobeams reaching a Vπ as low as 16 μV for sub-nanowatt pump powers. Without the associated optomechanical gain, we achieve a total (internal) pure conversion efficiency of up to 0.019% (1.6%), relevant for future noise-free operation on this qubit-compatible platform.},
author = {Arnold, Georg M and Wulf, Matthias and Barzanjeh, Shabir and Redchenko, Elena and Rueda Sanchez, Alfredo R and Hease, William J and Hassani, Farid and Fink, Johannes M},
issn = {2041-1723},
journal = {Nature Communications},
keywords = {General Biochemistry, Genetics and Molecular Biology, General Physics and Astronomy, General Chemistry},
publisher = {Springer Nature},
title = {{Converting microwave and telecom photons with a silicon photonic nanomechanical interface}},
doi = {10.1038/s41467-020-18269-z},
volume = {11},
year = {2020},
}
@article{10620,
abstract = {Partially filled Landau levels host competing electronic orders. For example, electron solids may prevail close to integer filling of the Landau levels before giving way to fractional quantum Hall liquids at higher carrier density1,2. Here, we report the observation of an electron solid with non-collinear spin texture in monolayer graphene, consistent with solidification of skyrmions3—topological spin textures characterized by quantized electrical charge4,5. We probe the spin texture of the solids using a modified Corbino geometry that allows ferromagnetic magnons to be launched and detected6,7. We find that magnon transport is highly efficient when one Landau level is filled (ν=1), consistent with quantum Hall ferromagnetic spin polarization. However, even minimal doping immediately quenches the magnon signal while leaving the vanishing low-temperature charge conductivity unchanged. Our results can be understood by the formation of a solid of charged skyrmions near ν=1, whose non-collinear spin texture leads to rapid magnon decay. Data near fractional fillings show evidence of several fractional skyrmion solids, suggesting that graphene hosts a highly tunable landscape of coupled spin and charge orders.},
author = {Zhou, H. and Polshyn, Hryhoriy and Taniguchi, T. and Watanabe, K. and Young, A. F.},
issn = {1745-2481},
journal = {Nature Physics},
keywords = {General Physics and Astronomy},
number = {2},
pages = {154--158},
publisher = {Springer Nature},
title = {{Solids of quantum Hall skyrmions in graphene}},
doi = {10.1038/s41567-019-0729-8},
volume = {16},
year = {2019},
}
@article{10621,
abstract = {Twisted bilayer graphene has recently emerged as a platform for hosting correlated phenomena. For twist angles near θ ≈ 1.1°, the low-energy electronic structure of twisted bilayer graphene features isolated bands with a flat dispersion1,2. Recent experiments have observed a variety of low-temperature phases that appear to be driven by electron interactions, including insulating states, superconductivity and magnetism3,4,5,6. Here we report electrical transport measurements up to room temperature for twist angles varying between 0.75° and 2°. We find that the resistivity, ρ, scales linearly with temperature, T, over a wide range of T before falling again owing to interband activation. The T-linear response is much larger than observed in monolayer graphene for all measured devices, and in particular increases by more than three orders of magnitude in the range where the flat band exists. Our results point to the dominant role of electron–phonon scattering in twisted bilayer graphene, with possible implications for the origin of the observed superconductivity.},
author = {Polshyn, Hryhoriy and Yankowitz, Matthew and Chen, Shaowen and Zhang, Yuxuan and Watanabe, K. and Taniguchi, T. and Dean, Cory R. and Young, Andrea F.},
issn = {1745-2481},
journal = {Nature Physics},
keywords = {general physics and astronomy},
number = {10},
pages = {1011--1016},
publisher = {Springer Nature},
title = {{Large linear-in-temperature resistivity in twisted bilayer graphene}},
doi = {10.1038/s41567-019-0596-3},
volume = {15},
year = {2019},
}
@article{8405,
abstract = {Atomic-resolution structure determination is crucial for understanding protein function. Cryo-EM and NMR spectroscopy both provide structural information, but currently cryo-EM does not routinely give access to atomic-level structural data, and, generally, NMR structure determination is restricted to small (<30 kDa) proteins. We introduce an integrated structure determination approach that simultaneously uses NMR and EM data to overcome the limits of each of these methods. The approach enables structure determination of the 468 kDa large dodecameric aminopeptidase TET2 to a precision and accuracy below 1 Å by combining secondary-structure information obtained from near-complete magic-angle-spinning NMR assignments of the 39 kDa-large subunits, distance restraints from backbone amides and ILV methyl groups, and a 4.1 Å resolution EM map. The resulting structure exceeds current standards of NMR and EM structure determination in terms of molecular weight and precision. Importantly, the approach is successful even in cases where only medium-resolution cryo-EM data are available.},
author = {Gauto, Diego F. and Estrozi, Leandro F. and Schwieters, Charles D. and Effantin, Gregory and Macek, Pavel and Sounier, Remy and Sivertsen, Astrid C. and Schmidt, Elena and Kerfah, Rime and Mas, Guillaume and Colletier, Jacques-Philippe and Güntert, Peter and Favier, Adrien and Schoehn, Guy and Schanda, Paul and Boisbouvier, Jerome},
issn = {2041-1723},
journal = {Nature Communications},
keywords = {General Biochemistry, Genetics and Molecular Biology, General Physics and Astronomy, General Chemistry},
publisher = {Springer Nature},
title = {{Integrated NMR and cryo-EM atomic-resolution structure determination of a half-megadalton enzyme complex}},
doi = {10.1038/s41467-019-10490-9},
volume = {10},
year = {2019},
}