"Quantum" comes from the Latin meaning "how much." It refers to the discrete units of matter and energy that make up every single object in the universe. The laws of physics that govern objects on a macroscopic scale are well understood, both scientifically and intuitively. At atomic and sub-atomic scales, these “classical” laws break down. At the turn of the twentieth century, a series of scientific crises challenged our perception of the world. What emerged from this period of scientific turmoil was the development of quantum mechanics, a theory that is as strange as it is precise in predicting the behavior of matter, the nature of chemical bonds, and the properties of materials like semiconductors and superconductors.
Quantum mechanics is the firm foundation on which all of physical science rests. It is the study of a system in terms of its most fundamental (and tiny) constituents such as electrons, neutrons, photons: particles that also act like waves—or is it waves having the properties of particles? On this atomic scale, which is governed by Planck’s constant, the properties of a system are very different than that of bulk matter. This diverging behavior leads to emerging phenomena that cannot be explained or accounted for in classical terms.
Quantum mechanics can thus predict or explain a variety of phenomena in a variety of systems, from the well established photoelectric effect to the transmission of information via entangled quantum objects. These phenomena arise from the concepts of quantum mechanics; for instance, the wave-particle duality allows electron to tunnel through classically unsurmountable barriers, the condensation of electrons into Cooper pairs, which is the basis of superconductivity, is made possible only because of Pauli’s exclusion principle. In addition, previously inaccessible states of matter such as photonic matter or topological insulators are being explored for applications that can revolutionize the modern world.
All those quantum phenomena and many more are the basis of technologies that are surreptitiously invading our daily life. Quantum mechanics is what drives lasers or determines the bonding of a drug to a protein. It is the basis of light-matter interactions and spectroscopic techniques.
Scientists at the University of Pittsburgh, Carnegie Mellon University, and Duquesne University work in diverse fields of physics, chemistry, and engineering towards a wide range of applications. They investigate surfaces and heterojunctions, quantum dots and potential energy surfaces, non-linear optical systems and entangled qubits. They postulate, develop, fabricate, characterize, calculate. The Pittsburgh Quantum Institute was founded to bring together those key players of the quantum scene in a unified yet diverse community for the promotion of quantum research.