Rabi cycle

The Rabi cycle is a term that originated in the field of quantum optics,

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but has recently found applications in the field of quantum computing.

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When an atom (or some other two-level system) is illuminated by a coherent beam of photons, it will cyclically absorb photons and re-emit them by stimulated emission. One such cycle is called a Rabi cycle and the inverse of its duration the Rabi frequency of the photon beam.

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This mechanism is fundamental to quantum optics. It can be modelled using the Jaynes-Cummings model and the Bloch vector formalism.

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For example, in a two-state atom (an atom in which an electron can either be in the excited or ground state), the probability of finding the atom in the excited state is found from the Bloch equations to be:

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|c_b(t)|^2=cos(omega t)^2 where omega is the Rabi frequency.

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More generally, one can consider a system where the two levels under consideration

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are not energy eigenstates. Therefore if the system is initialized in one of these

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levels, time evolution will make the population of each of the levels oscillate with

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some characteristic frequency, which is also known as the Rabi frequency.

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The name is in reference to Isidor Isaac Rabi.

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Two-level system: A two-level system is a quantum mechanics system in which there are two physical states of different energy. That is, if we take the time-independent Hamiltonian to be H, then we say that the two levels are psi_a and psi_b with corresponding energy eigenvalues E_a and E_b, which may or may not be di...

Absorb: redirect absorption...

Stimulated emission: In optics, stimulated emission is the process by which, when perturbed by a photon, matter may lose energy resulting in the creation of another photon. The perturbing photon is not destroyed in the process (cf. absorption), and the second photon is created with the same phase and frequency as the or...

Rabi cycle related Images and Photos (experimental)

Cycle	SUNDAY CYCLE	Naphta Cycle	Cycle of Life
Cycle and Bud	Cycle and Bud	Cycle World BMW R75 750	Cycle Savages 1970
Neon Spin Cycle	Cycle World BSA Spitfire MKIII Poster	The Moscow Cycle Works c.1930	Pendulum Half Cycle