What are the basis states used to represent the qubit in the implemented system?
In the field of quantum information, the basis states used to represent a qubit in an implemented system are commonly referred to as the computational basis states. These basis states are fundamental to the representation and manipulation of quantum information.
A qubit, or quantum bit, is the basic unit of quantum information. Unlike classical bits, which can exist in only two states (0 or 1), a qubit can exist in a superposition of these two states. The computational basis states, denoted as |0⟩ and |1⟩, correspond to the classical bit states 0 and 1, respectively. These states form the foundation upon which quantum algorithms and computations are built.
The |0⟩ state represents the qubit in the state of "0" with certainty, whereas the |1⟩ state represents the qubit in the state of "1" with certainty. However, the true power of qubits lies in their ability to exist in a superposition of these two basis states. This means that a qubit can be in a state that is a linear combination of |0⟩ and |1⟩, such as α|0⟩ + β|1⟩, where α and β are complex numbers known as probability amplitudes. The coefficients α and β determine the probability of measuring the qubit in the |0⟩ or |1⟩ state, respectively.
To illustrate this concept, let's consider an example. Suppose we have a qubit in the state α|0⟩ + β|1⟩, where α = 0.6 and β = 0.8. If we were to measure this qubit, the probability of obtaining the outcome |0⟩ would be |α|^2 = |0.6|^2 = 0.36, and the probability of obtaining the outcome |1⟩ would be |β|^2 = |0.8|^2 = 0.64. These probabilities must add up to 1, ensuring that the qubit is always in one of the basis states upon measurement.
It is important to note that the computational basis states |0⟩ and |1⟩ are not the only possible basis states for a qubit. In fact, any two orthogonal states can be used as basis states. However, the computational basis states are the most commonly used and provide a convenient framework for representing and manipulating quantum information.
The basis states used to represent a qubit in an implemented system are the computational basis states |0⟩ and |1⟩. These states form the foundation of quantum information and enable the representation and manipulation of quantum information. By existing in a superposition of these basis states, qubits possess the unique ability to perform quantum computations and algorithms.
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