Chapter 5: Understanding the Quantum Bit (Qubit)

We are all very familiar with the classic bit, or just bit, with respect to current computer hardware systems. It is the fundamental unit used to compute everything from simple mathematical problems, such as addition and multiplication, to more complex algorithms that involve a large collection of information.

Quantum computers have a similar fundamental unit called a quantum bit or qubit, as it is commonly referred to. In this chapter, we will describe what a qubit is, both from a mathematical (computational) and hardware perspective. We will cover the differences between qubits and bits, particularly regarding how calculations are defined. This chapter will then transition from single to multi-qubits and talk about the advantages of multi-bits.

We will also provide an overview of the various hardware implementations and how the different quantum systems implement their qubits to compute information. Finally, we will discuss how...