Articles in 2023

The hierarchical equations of motion approach is useful for the non-perturbative study of complex open quantum systems, which are simultaneously coupled to both bosonic and fermionic environments. To tackle these systems, the authors introduce an open-source software package (HierarchicalEOM.jl), characterized by a notable speed and accessibility to new users.

The properties of cognitive microswimmers in fluids are determined by their capability to sense a target, process information, and adapt the motion, and by hydrodynamic interactions. To gain insight on this process, the authors investigate pursuer-target pairs, for pursuers with implicitly sensing, and self-steering with limited maneuverability.

The dynamic network biomarker/marker (DNB) method is popular to detect critical points from measured data, but a unified criterion to select the most appropriate DNB is still lacking. The authors propose a giant-componentbased DNB method that directly selects the largest DNB as transition core, reflecting the progress of the transition.

The description of open systems featuring anti parity-time symmetry builds on the assumption that the system does not retain memory. Here, the authors propose a system with anti-PT-symmetry where a single time-delay encodes the retention of memory, and experimentally demonstrate it by coupling two time-delay semiconductor lasers.

Coulomb Explosion imaging is a promising technique to study the ultrafast nuclear dynamics which underpin molecular photochemistry. By initiating Coulomb explosion through soft X-ray ionization, the authors are able to image ultrafast nuclear dynamics of a prototypical photoreaction.

Superconductors with odd-parity Cooper pairs are rare and their experimental confirmation is significantly challenging. In the CeRh2As2 superconductor, the authors’ investigation reveals that the presence of competing pairings with opposite parities gives rise to a unique collective mode, which can be observed through the optical response.

The quantum distance quantifies the similarity between two quantum states and plays a relevant role in the physics of flat bands, e.g. flat band superconductivity or Landau levels. The authors propose a construction scheme for tight-binding models hosting a singular flat band with a prescribed maximum quantum distance and establish a bulk-boundary correspondence between the quantum distance and the boundary modes.

Ultra-thin endoscopes based on multimode fibers can achieve cellscale imaging in deep tissues, but in-vivo imaging perturbs the fiber so it must be re-calibrated with access to a single end only. To circumvent the problem, the authors rely on neural networks and implement a single-ended recovery of the fiber’s transmission matrix.

Boundary time crystals are gaining attention due to their distinctive features like persistent oscillations at the thermodynamic limit. This work shows that the boundary time crystal phase transition can be exploited for quantum-enhanced sensitivity, which bridges many-body physics and quantum metrology and hence triggers broad interest in the condensed matter and quantum technology communities.

Heterodyne detection is vastly used to overcome the intrinsic electron spin lifetime limiting the spectral resolution in NMR experiments based on nitrogen vacancy platforms, but the application of this technique at high magnetic fields is yet a challenge. The authors introduce heterodyne detection method applicable at high magnetic fields.

Platicons microcombs can be generated in photonic molecules from a continuous-wave pump, but their spectrum is typically distorted. The authors observe the formation of a platicon microcomb using a photonic molecule realized with two coupled microcavities, resulting in engineered microcomb spectrum approaching the ideal single microresonator case.

Anisotropic environments affect the motion of many living organisms but studying these systems in a controlled environment can be challenging. We employ experiments using active granular particles on a striated substrate and use the theory of active Brownian motion to replicate and describe such anisotropic motility.

The quantum nature of the hydrogen lattice in superconducting hydrides can have crucial effects on the material’s properties. In this work, the authors focus on the low-pressure superconductor BaSiH₈ and identify the structural change due to quantum ionic effects to be the main driving force in increasing the critical pressure of dynamic stability.

Quantum communications over long distances require the use of a modular structure composed of quantum repeater nodes, and color centers in diamond are a promising candidate to establish such nodes. The authors present an open cavity platform using SiV centers in nanodiamond as a spin-photon interface with a view to realizing a quantum repeater.

The realization of a continuous-wave room-temperature maser reinvigorated the maser as a platform for microwave research in a broad range of applications, yet the operative conditions are still non-optimized. The authors optimize the operating space of a maser using NV- centers in terms of quality factor of the resonator and spin-level-inversion.

Generative autoregressive neural networks have recently enjoyed both scientific and commercial applications in image and language generation tasks. This work presents an exact mapping of the Boltzmann distribution, ubiquitously used in statistical mechanics, of pairwise interacting spin systems as an autoregressive neural network, exemplified by applications in the Curie–Weiss and Sherrington–Kirkpatrick models.

Coherent phonons can modify the wavefunction topology of quantum materials, yet the implications for electron dynamics remain to be addressed. The authors use time-dependent approaches to simulate the effect of coherent phonons, induced by strong terahertz laser field, on the electronic carrier dynamics in the topological insulator Zirconium Pentatelluride.

Self-motile active matter particles form a motility-induced phase separation (MIPS) state for high density and activity. By introducing an infection that causes particles to become nonmotile, MIPS clustering can arise outside the MIPS regime and exhibits time-dependent patterning from MIPS to a wetting phase and a fragmented state.

High-order Van Hove singularities (hoVHSs) with power-law divergences in the density-of-states are drawing current interest mainly in context of two-dimensional (2D) twisted moiré materials. Using cuprate high-Tc superconductors as an example, here the authors illustrate complications that can arise in bulk materials in defining hoVHSs and the need to extend the definition of hoVHSs to include flat-band materials.