Understanding of Quantum Tomography for Determining the Superposed and Entangled States in Quantum Computing

Abstract

In this brief review paper aims at the understanding of experimental and theoretical work done so far on the quantum tomography and its relevance to quantum computing. In order to determine ortho normal and entangled states the procedure adopted is explained and understanding of two superposition states in a qubit is defined. The concept of the Bloch sphere to understand the reconstruction of quantum states is also discussed. Attempt has been made to understand various mathematical techniques used by other authors to determine state superposition by efficient algorithms such as Shore’s and Grover’s algorithms. The basic experimental technique used in quantum tomography to experimentally determine the orthogonal and superposition states uses homodyne balanced detection which is discussed and described in detail here. Also explain a simple procedure for writing and reading a qubit. A complete characterization procedure is discussed for any quantum state of two orthogonally polarized states and the paper gives a systematic procedure to collect the necessary data.