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What gate acts as a quantum bit?
Toffoli gate
The Toffoli gate has a direct quantum equivalent, showing that quantum circuits can perform all operations performed by classical circuits.
What is a gate in quantum computing?
A quantum gate or quantum logic gate is a rudimentary quantum circuit operating on a small number of qubits. They are the analogues for quantum computers to classical logic gates for conventional digital computers. Quantum logic gates are reversible, unlike many classical logic gates.
How many states can a qubit have?
two states
Like bits, qubits can be in one of two states when measured, but that’s where the similarities end. Qubits us quantum mechanical phenomena like superposition and entanglement to exist in multiple states at the same time until measured and to hold up to two bits worth of data.
What happens when you say yes or no to a quantum gate?
It takes in two bits of information, and generates a 1 if both incoming bits are 1s. So, if both business people say “yes” (1) to the deal, the AND gate will output 1. If one or both say “no” (0), the AND gate generates a 0 or a no.
How are quantum logic gates and classical logic gates alike?
If nothing else, classical logic gates and quantum logic gates are both logic gates. So let’s start there.
How are qubits represented in a quantum logic gate?
Quantum logic gates are represented by unitary matrices. The number of qubits in the input and output of the gate must be equal; a gate which acts on n {displaystyle n} qubits is represented by a 2 n × 2 n {displaystyle 2^{n}times 2^{n}} unitary matrix.
Are there any reversible gates in a quantum circuit?
They are the building blocks of quantum circuits, like classical logic gates are for conventional digital circuits. Unlike many classical logic gates, quantum logic gates are reversible. However, it is possible to perform classical computing using only reversible gates.