Tools of Quantum Information Theory
M. S. Ramkarthik, Payal D. Solanki · 2021
This chapter contains recipes of all the major quantum gates used in performing various quantum information tasks. It also has some useful recipes on the construction of N qubit computational basis, N qubit Greenberger-Horne-Zeilinger states, N qubit W states, two-qubit Bell states, N qubit generalized Werner states. Apart from that, entropy and its quantification by various measures like Shannon entropy, linear and Relative entropy are given. It becomes very important in quantum information theory to know the closeness between two quantum states and to this end, recipes related to trace distance, fidelity, super fidelity, Bures distance. The chapter ends with two important recipes which are for computing the expectation values of observables and the quantum mechanical single qubit measurements.