Bell basis

The '''Bell basis''' is a basis for the Hilbert space of a 2-qubit system where the basis vectors are defined in terms of the [[computational basis]] as : :$\backslash begin\{cases\}\; |\backslash Psi^-\; \backslash rangle\; =\; \backslash frac\{1\}\{\backslash sqrt\{2\}\}(|01\backslash rangle\; -\; |10\backslash rangle)\; \backslash \backslash \; |\backslash Psi^+\; \backslash rangle\; =\; \backslash frac\{1\}\{\backslash sqrt\{2\}\}(|01\backslash rangle\; +\; |10\backslash rangle)\; \backslash \backslash \; |\backslash Phi^-\; \backslash rangle\; =\; \backslash frac\{1\}\{\backslash sqrt\{2\}\}(|00\backslash rangle\; -\; |11\backslash rangle)\; \backslash \backslash \; |\backslash Phi^+\; \backslash rangle\; =\; \backslash frac\{1\}\{\backslash sqrt\{2\}\}(|00\backslash rangle\; +\; |11\backslash rangle)\; \backslash end\{cases\}$ The quantum states represented by these vectors are called [[Bell state]]s and are maximally entangled. Density matrices which are diagonal in this basis are called [[Bell-diagonal state|Bell-diagonal]]. == See also == * [[Bell state]] {{stub}} [[Category:Quantum States]]