Qubit
In quantum computing, a qubit () or quantum bit (sometimes qbit) is the basic unit of quantum information—the quantum version of the classical binary bit physically realized with a two-state device. A qubit is a two-state (or two-level) quantum-mechanical system, one of the simplest quantum systems displaying the peculiarity of quantum mechanics. Examples include: the spin of the electron in which the two levels can be taken as spin up and spin down; or the polarization of a single photon in which the two states can be taken to be the vertical polarization and the horizontal polarization. In a classical system, a bit would have to be in one state or the other. However, quantum mechanics allows the qubit to be in a coherent superposition of both states/levels simultaneously, a property which is fundamental to quantum mechanics and quantum computing.
Pittsburgh Quantum Institute
PQI researchers work on various aspects of quantum computing and information. Development in information theory as well as in quantum algorithms is carried out. Qubit platforms, such as superconducting microwave circuits and Majorana Fermions in semiconducting nanowires are designed for quantum computing. Quantum simulation is another approach to quantum computing; the experimental thrust is the design of a 1D solid state quantum simulation platform that can be controlled on the nanoscale, while a theoretical approach consists of the development of powerful numerical methods that would open the door to faster, more accurate simulations of various novel and exotic quantum systems on a classical computer.