Who first proposed the idea of quantum computing using qubits?

Question

As I understand it, the field of quantum mechanics was started in the early 20th century when Max Planck solved the black-body radiation problem. But I don't know when the idea of computers using quantum effects spread out.

What is the earliest source that proposes the idea of quantum computers using qubits?

Answer 1

According to Wikipedia of Timeline of quantum computing, here are the main events:

• 1960

  Stephen Wiesner invents conjugate coding.

• 1968

  A quantum computer with spins as quantum bits was also formulated for use as a quantum spacetime in 1968.

  ^{Finkelstein, David (1968). "Space-Time Structure in High Energy Interactions". In Gudehus, T.; Kaiser, G. Fundamental Interactions at High Energy. New York: Gordon & Breach.}

• 1973

  Alexander Holevo publishes a paper showing that n qubits cannot carry more than n classical bits of information (see: "Holevo's theorem"/"Holevo's bound").

  Charles H. Bennett shows that computation can be done reversibly.

• 1976

  Polish mathematical physicist Roman Stanisław Ingarden publishes a seminal paper entitled "Quantum Information Theory" in Reports on Mathematical Physics, vol. 10, 43–72, 1976.

• 1980

  Paul Benioff described quantum mechanical Hamiltonian models of computers

  Yuri Manin proposed an idea of quantum computing

• 1981

  Richard Feynman in his talk [...], observed that it appeared to be impossible in general to simulate an evolution of a quantum system on a classical computer in an efficient way. He proposed a basic model for a quantum computer that would be capable of such simulations

• 1982

  Paul Benioff proposes the first recognisable theoretical framework for a quantum computer.

So in general, the field of quantum computing was initiated by the work of Paul Benioff ^study and Yuri Manin in 1980, Richard Feynman in 1982 ^study, and David Deutsch in 1985. Source: Quantum computing at Wikipedia.

Answer 2

Around 1960-1973 the idea was beginning to form, but the field really started spreading in the 1980s.

One of the biggest pioneers was Richard P. Feynman. He proposed a model of a quantum computer in his talk. From that talk, many other scientists pushed the field further (Toffoli created one of the first quantum gates; Shor, at Bell Labs, created one of the first quantum algorithms etc.)

The field has been changing and evolving rapidly throughout 1980-2000, and keeps evolving. But the initial "spark" was made by Richard Feynman. I don't know if he thought of qubits, but his main interest in quantum computing was for simulating quantum physics and systems.