Hall effect

The Hall effect is a phenomenon observed in electrical conductors and semiconductors when they are placed in a magnetic field perpendicular to the direction of an electric current. It was discovered by Edwin Hall in 1879. When a current-carrying conductor is subjected to a magnetic field, the motion of the charged particles (such as electrons) in the conductor is affected by the magnetic field.

The Advanced Electric Propulsion System (AEPS) refers to innovative spacecraft propulsion technologies that utilize electric power to generate thrust. These systems are designed to achieve greater efficiency, higher specific impulse, and longer mission durations compared to traditional chemical propulsion systems. AEPS includes various technologies, such as: 1. **Ion Propulsion**: This method uses electric fields to accelerate ions, creating thrust.

A **composite fermion** is a concept used in condensed matter physics, particularly in the study of the quantum Hall effect and two-dimensional electron systems. The idea is that under certain conditions, such as in a high magnetic field and low temperature, the behavior of electrons can be effectively described as being made up of composite particles rather than individual electrons.

Edwin Hall could refer to a couple of different things depending on the context: 1. **Edwin Hall (Physicist)**: Edwin Herbert Hall (1855–1938) was an American physicist best known for discovering the Hall effect in 1879. The Hall effect is the production of a voltage difference across a conductor when an electric current flows through it and is placed in a magnetic field.

The fractional quantum Hall effect (FQHE) is a phenomenon that occurs in two-dimensional electron systems subjected to strong magnetic fields and low temperatures. This effect is characterized by the existence of quantized Hall conductance at fractional values of the fundamental quantum of conductance, which is e²/h, where "e" is the charge of an electron and "h" is Planck's constant. The FQHE was first observed in 1982 by David Thouless, F. Duncan M.

A Hall-effect thruster (HET) is a type of electric propulsion system used primarily in spacecraft. It operates by utilizing the Hall effect to generate thrust through ionized propellant. Here is how it works: 1. **Ionization**: The thruster uses a noble gas, typically xenon, as propellant. Inside the thruster, this gas is ionized by an electric discharge, which turns it into plasma consisting of positively charged ions and free electrons.

Hofstadter's butterfly is a fractal pattern that appears in the study of electron behavior in a two-dimensional lattice subjected to a magnetic field. It is named after Douglas Hofstadter, who introduced it in his 1976 paper, "Energy Levels and Wave Functions of a Two-Dimensional Electron Gas in a Magnetic Field." The phenomenon arises when examining the energy levels of electrons in a periodic potential (like a crystal lattice) under the influence of a magnetic field.

The Iodine Satellite refers to a satellite developed by the company Iodine as part of its efforts to provide advanced satellite-based services. One significant application of the Iodine Satellite is in Earth observation and communication, particularly for broadband connectivity, remote sensing, and various other applications in space technology. Iodine has aimed to leverage small satellite technology and deploy a constellation of such satellites to enhance the accessibility and performance of satellite communication services.

The Laughlin wavefunction is a product of the field of condensed matter physics and quantum mechanics, specifically relating to the fractional quantum Hall effect (FQHE). It was introduced by Robert Laughlin in 1983 as a theoretical description of the ground state of a two-dimensional electron gas subjected to a strong magnetic field.

The Quantum Hall transition refers to the phenomenon observed in two-dimensional electron systems subjected to strong magnetic fields at low temperatures, leading to quantized Hall conductance. This occurs when the system transitions between different quantum Hall states, characterized by distinct plateaus in the Hall conductance as the magnetic field is varied.

The Quantum Anomalous Hall Effect (QAHE) is a phenomenon in condensed matter physics that occurs in certain materials, particularly topological insulators and ferromagnetic systems with strong spin-orbit coupling. It is a quantum version of the classical Hall effect, wherein an electric current flowing in a two-dimensional conductor generates a transverse voltage in the presence of a magnetic field.

SMART-1, which stands for Small Missions for Advanced Research and Technology, was a European Space Agency (ESA) spacecraft that was launched on September 27, 2003. It was primarily designed as a technology demonstration mission to test various new technologies for future spacecraft.

The semicircle law is a concept that arises in the context of the quantum Hall effect, particularly in relation to the energy spectrum of two-dimensional electron systems in strong magnetic fields. The quantum Hall effect itself is observed in a two-dimensional electron gas (2DEG) when subjected to low temperatures and strong magnetic fields, leading to quantized Hall conductance and unusual electronic behaviors.

The Thermal Hall effect, often referred to as the "thermal Hall effect" or "thermal Hall conductivity," describes a phenomenon related to the transport of heat in a material subjected to a temperature gradient in the presence of a magnetic field. In a typical scenario, when a temperature difference is established across a material (for example, by heating one side), heat flows from the hot side to the cold side.

The Van der Pauw method is a widely used technique for measuring the electrical properties of thin films and materials, particularly their sheet resistance and carrier concentration. Named after the physicist Leo van der Pauw, this method is especially useful for characterizing uniform, isotropic samples such as films and polycrystalline materials that have arbitrary shapes, provided they can be treated as being of constant thickness.