Colossal magnetoresistance (CMR) refers to a significant change in the electrical resistance of a material in response to an applied magnetic field. This phenomenon is especially pronounced in certain types of manganese oxides, such as perovskite materials. CMR can be defined as an increase in resistance by several orders of magnitude when a magnetic field is applied, compared to the resistance observed in the absence of a magnetic field.

Bipolar magnetic semiconductors are a class of materials that exhibit both magnetic properties and semiconductor characteristics. These materials can conduct electricity like traditional semiconductors while also displaying magnetic ordering, which is typically associated with ferromagnetic or antiferromagnetic behavior. The term "bipolar" in this context often refers to the ability of the semiconductor to support both types of charge carriers: electrons (negative charge carriers) and holes (positive charge carriers).

A biexciton is a quantum mechanical state that consists of two excitons. An exciton is a bound state of an electron and a hole (the absence of an electron) in a semiconductor or insulator. When an electron in a semiconductor absorbs energy (such as from a photon), it can be excited from the valence band to the conduction band, leaving behind a hole in the valence band. The electron and hole can then interact through electrostatic attraction, forming an exciton.

The Journal of Molecular Spectroscopy is a scientific journal that focuses on research in the field of molecular spectroscopy. It publishes original research articles, reviews, and short communications that address various aspects of molecular spectroscopy, including theoretical, experimental, and computational studies. Molecular spectroscopy is the study of the interaction of electromagnetic radiation with molecular species, and it plays a critical role in understanding molecular structure, dynamics, and interactions.

A matrix of ones is a matrix in which every element is equal to one. It can be represented in various shapes and sizes, such as a 2x3 matrix, a 4x4 matrix, or any \( m \times n \) matrix, where \( m \) is the number of rows and \( n \) is the number of columns.

Dexter electron transfer, often referred to in the context of quantum chemistry and solid-state physics, is a mechanism of electron transfer that involves quantum tunneling. This process typically occurs between two molecules that are in close proximity and involves the transfer of an electron from one molecular orbital to another, even when they are not directly in contact.

The depolarization ratio is a term commonly used in the fields of optics, atmospheric science, and remote sensing to describe the degree of light polarization change after scattering, particularly in relation to particles or aerosols in the atmosphere. It is defined as the ratio of the intensity of the scattered light that is polarized to the intensity of the light that is unpolarized or the total intensity of the light.

Dark current spectroscopy is a technique used in the field of spectroscopy to analyze the properties of materials and detect specific phenomena, often in the context of photodetectors and other devices that interact with light. The "dark current" refers to the electrical current that flows through a photodetector in the absence of light, which can arise from thermal excitation of charge carriers, defects, and other mechanisms.

Vapor phase decomposition is a chemical process where a compound is broken down into its constituent parts (or simpler substances) in the vapor phase, usually through the application of heat or by exposure to a reactive environment. This process is often utilized in various industrial and laboratory applications, such as in the synthesis of materials, the purification of substances, or in chemical analysis.

Spin-polarized electron energy loss spectroscopy (SPEELS) is a sophisticated technique used to investigate the electronic and magnetic properties of materials at the nanoscale. This method combines aspects of traditional electron energy loss spectroscopy (EELS) and spin-polarized techniques to provide insights into the spin states of electrons in materials.

Spectroscopy Letters is a scientific journal that publishes research articles, reviews, and brief communications focused on the field of spectroscopy. Spectroscopy is a technique used to analyze the interaction between matter and electromagnetic radiation, and it has applications in various fields including chemistry, physics, material science, biology, and environmental science. The journal typically covers a wide range of topics related to spectroscopic techniques, including but not limited to infrared, ultraviolet, visible, and Raman spectroscopy.

Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy is a scientific journal that focuses on the field of spectroscopy, particularly related to molecules and biomolecules. The journal publishes original research articles, reviews, and other types of scholarly content that explore various spectroscopic techniques and their applications in a wide range of scientific disciplines, including chemistry, biochemistry, and materials science.

The Journal of Raman Spectroscopy is a scientific publication that focuses on research related to Raman spectroscopy and its applications. Raman spectroscopy is a spectroscopic technique used to observe vibrational, rotational, and other low-frequency modes in a system. This technique is widely used in chemistry, biology, materials science, and various fields for analyzing molecular structures, chemical compositions, and interactions. The journal publishes original research articles, reviews, and technical notes that contribute to the advancement of knowledge in Raman spectroscopy and related techniques.

Applied Spectroscopy is a peer-reviewed scientific journal that focuses on the field of spectroscopy, which is the study of the interaction between matter and electromagnetic radiation. The journal covers a wide range of topics related to various spectroscopic techniques, including but not limited to infrared, ultraviolet-visible, nuclear magnetic resonance (NMR), mass spectrometry, and Raman spectroscopy.

Wolfgang Demtröder is a notable figure in the field of physics, particularly known for his work in spectroscopy and quantum mechanics. He is recognized for his contributions to the understanding of atomic and molecular interactions and has authored several textbooks and research papers on these subjects. One of his well-known works is the textbook "Laser Spectroscopy: Basic Concepts and Practical Methods," which is widely used in the educational sector for teaching concepts related to laser spectroscopy.

William de Wiveleslie Abney (1847–1932) was a British chemist and photographer known for his significant contributions to the field of photography, particularly in the study of light and color. He is best known for his work on photographic processes and the development of the "Abney method" of measuring the color and quality of light.

An astro-comb is a sophisticated astronomical instrument that combines the functions of an optical frequency comb and a spectrograph. It is designed to create highly accurate and precise measurements of the spectrum of light from astronomical objects. Optical frequency combs produce a series of evenly spaced, discrete frequency lines (or modes) that can be used as a ruler for measuring optical frequencies with extraordinary precision.

William Swan (1924–2015) was a notable physicist known for his contributions to various fields, particularly in the area of electromagnetic theory and its applications. He had a significant influence in the study of physics and was involved in research and academic pursuits throughout his career.

William P. Bidelman is a prominent figure in the field of psychology, particularly known for his contributions to the study of personality and social psychology. His work has often focused on how personality traits and social behaviors influence individual decision-making and interactions.

William Huggins (1824–1910) was a prominent English astronomer known for his pioneering work in astrophysics. He is particularly noted for his contributions to the study of spectroscopy, which is the analysis of the light emitted or absorbed by materials. Huggins was one of the first astronomers to apply spectroscopy to the study of celestial bodies, helping to determine their composition, temperature, and motion.