There is an ensemble qubitwhich contain a large number of particles that together act as a single qubit and there is what one typically thinks of as a qubit, which is a single particle or material.
Possible qubits include single photons, trapped atomic ions, neutral atoms, nuclear spins, quantum dots, impurities in silicon and diamond, etc...
LECTURES
If you’re looking for a little more in-depth information about quantum-computers and quantum-computing, here are some of our favorite lectures on the subject
In this video, John Preskill talks about quantum-computing and the entanglement frontier - and how quantum information is fundamentally different from information in our macroscopic world:
Feynman’s famous computer heuristics lecture.
In this video, the always-entertaining 1965 Nobel Prize Winner Richard Feynman gives you an introduction to computer heuristics and metaheuristics.
How do computers work? How do computers file information? How do computers handle data? How do computers use their information? And how do computers actually compute values of interest to human beings? Mr. Feynman can explain!…
QUANTUM COMPUTING LECTURES & VIDEOS
In the following four videos, Prof. Michael Nielsen introduces the basic concepts of quantum computing and quantum computers as part of his popular video series -Quantum Computing for the Determined:
The qubit
Our first quantum gate: the quantum NOT gate
Tips for working with qubits
General single-qubit gates
In this lecture, Prof. Allan Adams of MIT’s Physics Department discusses the basic principles of quantum computing. The no-cloning theorem and Deutsch-Jozsa algorithms are introduced. And other topics covered include the EPR experiment and Bell's inequality: