Category
page 1Quantum states
wave function
mathematical description of the quantum state of a system; complex-valued probability amplitude, and the probabilities for the possible results of measurements made on the system can be derived from it
quantum state
state of an isolated quantum system, represented as an element of a projective Hilbert space
qubit
thumb|upright=0.6|The general definition of a qubit as the quantum state of a two-Energy level|level quantum system
In quantum computing, a qubit () or quantum bit is a basic unit of quantum information; a binary qudit the quantum version of the classic 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 pho
excited state
quantum states with more energy than the lowest possible amount
ground state
lowest energy state of quantum-mechanical system
vacuum state
quantum state with the lowest possible energy
bound state
system where a particle is subject to a potential such that the particle has a tendency to remain localised in one or more regions of space
singlet state
special low-energy state in quantum mechanics
Bell state
quantum state of two qubits that exhibits maximal quantum entanglement
coherent state
specific quantum state of the quantum harmonic oscillator, often described as a state which has dynamics most closely resembling the oscillatory behavior of a classical harmonic oscillator
triplet state
quantum state of a system with a spin of quantum number s =1, such that there are three allowed values of the spin component, ms = −1, 0, and +1
displaced squeezed state
quantum state in which an observable has an uncertainty smaller than that of a coherent state, compensated for by a larger uncertainty in the conjugate observable
Greenberger–Horne–Zeilinger state
highly entangled quantum state of 3 or more qubits
doublet state
mixed quantum state of a system with a spin of 1/2, such that there are two allowed values of the spin component, −1/2 and +1/2
W state
entangled 3-qubit quantum state
cat state
quantum superposition of two coherent states
NOON state
quantum-mechanical many-body entangled state representing a superposition of N particles in one mode with 0 particles in another, and vice versa
KMS state
mixed state describing a system in thermal equilibrium
squeezed state of light
quantum state of light, where the uncertainty in some quadrature direction is less than that of vacuum