A gauge theory is any number of quantum field theories put forward to explain fundamental interactions. In these theories the interactions between particles can be explained by the exchange of particles such as gluons, photons, and W and Z bosons. A gauge theory involves a symmetry group for the fields and potentials (the gauge group) […]
Entanglement entropy is a measure of the degree of quantum entanglement between two subsystems constituting a two-part composite quantum system. But entanglement entropy also quantifies the information shared between a subsystem and its environment in a quantum many-body wavefunction. Interestingly, the finite-size scaling form of entanglement entropy has contributions that depend uniquely on universal physical […]
Numerous physical systems—from classical electromagnetic fields to quantum particle fields—exhibit oscillating wave behavior. Specific settings exist, both in nature and in artificial systems, where these waves form patterns with holes, loops, and other distinct topological characteristics, often referred to as topological wave structures. Now, a team of researchers describes how these structures, which have previously […]
Phase transitions and their related phenomena lie at the core of modern statistical mechanics and condensed matter physics. At equilibrium, an intriguing aspect of second-order phase transitions is that systems with distinct order parameters can be described by the same set of static critical exponents, a hallmark of universality. Thomas Kibble’s research on phase transitions […]
Thomas Kibble’s research on phase transitions and topological defects is most significant. Actually, the Kibble-Zurek mechanism (KZM) is a paradigmatic theory to describe the dynamics across both classical continuous phase transitions and quantum phase transitions. The Kibble-Zurek mechanism describes the non-equilibrium dynamics and the formation of topological defects in a system which is driven through […]
At the nanoscale, even the most basic quantum size effect, the induction of semiconducting gaps by electron confinement, requires ultimate precision. The case of graphene is a dramatic example, where deviations of a single atom in width can induce dramatic variations of the gap. As a consequence, local defects or variations in width can severely […]
In the search for novel materials, the simulation of quantum matter is an extremely demanding computational task, which is expected to profit substantially from the surge of quantum technologies. Quantum algorithms for programmable quantum computers offer the most flexible approaches, but tailor-made quantum simulators are particularly well suited for large-scale simulations. For instance, tremendous efforts […]
A model of a physical system that can be solved exactly and the dynamics of which are characterized by regular rather than chaotic motion is called an integrable model. Integrable models can occur in Newtonian mechanics and quantum mechanics, with the harmonic oscillator being an example of such a model in both cases. Integrability has […]
In most physical systems, particles interact locally or at short distances only. Still, l ong-range interactions, like electromagnetic forces, play a crucial role in quantum physics and chemistry. They are a key ingredient for many phenomena, from molecular binding to high-temperature superconductivity. While their exact treatment in quantum many-body systems remains numerically challenging, analog quantum […]
It is very difficult to obtain exact solutions to systems involving interactions between more than two bodies, using either classical mechanics or quantum mechanics. To understand the physics of many-body systems, it is necessary to make use of approximation techniques or model systems that capture the essential physics of the problem. T he complexity of […]