Reviews & Analysis

The recent measurement of a nonlinear Hall effect has provided a new way to probe the spectral, symmetry and topological properties of quantum materials. This Perspective discusses the open questions around this new effect and potential applications.

Scientists studying cultural heritage use a variety of physics techniques to understand how pieces were made, their history and how to best preserve them. Six scientists who use different techniques describe their work — and how working with cultural heritage can lead to physics developments, too.

Blending occurs when multiple sources of light occupy the same region of the sky. This Perspective discusses the problems arising from blending for astrophysical and cosmological studies, and introduces the two main strategies for solutions.

The advent of commercial quantum devices has ushered in the era of near-term quantum computing. Variational quantum algorithms are promising candidates to make use of these devices for achieving a practical quantum advantage over classical computers.

Gaussian process regression (GPR) is a powerful, non-parametric and robust technique for uncertainty quantification and function approximation that can be applied to optimal and autonomous data acquisition. This Review introduces the basics of GPR and discusses several use cases from different fields.

The Weyl orbit is a type of cyclotron orbit that appears in topological semimetals. This Perspective discusses the Weyl orbit in the context of the 3D quantum Hall effect and provides an outlook on new phenomena that can arise from these states.

The Higgs boson is central to our understanding of the structure of matter in high-energy particle physics: the origin of mass, stability of the vacuum and key issues in cosmology. Here we review recent progress in experiment and theory and the prospects for future discoveries.

Magnetic molecules have been widely proposed for different quantum technologies due to their bewildering quantum properties. This Review describes techniques of paramount importance for the characterization, understanding and, ultimately, manipulation of the electronic properties of these systems.

Phonon heat conduction at the microscale and the nanoscale exhibits rich phenomena beyond the predictions of Fourier’s law, rivalling the phenomena of electrons. This Review discusses phonon heat conduction regimes, including the Casimir–Knudsen size effect, hydrodynamic transport, coherent transport (from quantization and localization) and divergence.

The rotations of levitated particles can show pronounced quantum effects, enabling tests of quantum physics and torque measurements with unprecedented sensitivity. Breakthroughs in cooling and controlling nanorotors set the stage for such experiments.

Quantitative magnetic resonance imaging and in vivo histology go beyond standard magnetic resonance imaging, aiming at characterizing tissue microstructure of the living brain. This Technical Review discusses advances in concepts, instrumentation, biophysical models and validation approaches facilitating this rapidly developing field.

Majorana zero modes are non-Abelian anyons that hold promise for realizing topologically protected quantum computation. This Review discusses how scanning tunnelling microscopy can identify Majorana zero modes and investigate their properties, and outlines future research direction of the field.

The recent discovery of higher-order band topology in topological insulators has unveiled the hierarchical structure of topological band theory. This Perspective reviews this rapidly developing field and discusses future directions, including open challenges, future trends, synergy and its use in other fields and potential applications.

The interconnectedness of the financial system is increasing over time, and modelling it as a network captures key interactions between financial institutions. This Review surveys the most successful applications of statistical physics and complex networks to the description and understanding of financial networks.

Despite decades of intense theoretical, experimental and computational effort, a microscopic theory of high-temperature superconductivity is not yet established. Eight researchers share their contributions to the search for a better understanding of unconventional superconductivity and their hopes for the future of the field.

Quantum annealing is a widely used heuristic algorithm for optimization and sampling, implemented in commercial processors. This Review provides a critical assessment of the field and points to new opportunities for a quantum advantage via recently developed alternative quantum annealing protocols.

The rapidly developing field of physics-informed learning integrates data and mathematical models seamlessly, enabling accurate inference of realistic and high-dimensional multiphysics problems. This Review discusses the methodology and provides diverse examples and an outlook for further developments.

Theoretical high-energy and condensed-matter physics share various ideas and tools. New connections between the two have been established through quantum information, providing exciting prospects for theoretical advances and even potential experimental studies. Six scientists discuss different directions of research in this inter-disciplinary field.

Over the last decade, ionic gate spectroscopy has developed into a powerful technique to measure gaps and band offsets of atomically thin semiconductors. Here, we provide a detailed overview of the technique, discussing results obtained on different 2D semiconducting materials.

The chiral anomaly, originally studied in pion decay, leads to related effects in Dirac and Weyl semimetals. This Review surveys recent experiments that address the appearance of the anomaly in parallel electric and magnetic fields.