Nutariel: Rabi Oscillation

Quantum Foundations arc, page 21 of 193. Back to The Pixelated Physics Universe

Who they are

Nutariel has one line, and says it often: “Awake. asleep. awake. rabi flopping.”

Nutariel is a character of the Quantum Foundations arc: drawn in pixels, ruled by one piece of real physics, and never allowed to break it.

The physics

Rabi oscillation: a driven two-level system oscillates between states with P(t) = sin²(Ωt/2) on resonance.

$$ \begin{gathered} P(t) = \sin^{2}\!\left(\frac{\Omega t}{2}\right) \end{gathered} $$

Symbol Meaning SI unit
$P(t)$ probability of the excited state (on resonance) —
$\Omega$ Rabi frequency rad/s
$t$ time s

Sources

Crossovers

Nutariel meets Zeno (Quantum Zeno Effect / The Observer). Nutariel starts drifting from one state to the other, sin²(Ωt/2) at a time. Zeno checks on her again and again, and each look sends her back to the start before she can get far. Watched often enough, Nutariel hardly flops at all.

Nutariel meets Chronolith (Discrete Time Crystal). Nutariel flops at the drive's own rhythm. Chronolith, driven at period T, answers at 2T, and keeps that rhythm stable against small errors because many interacting spins lock it in. One is a single two-level system; the other is a phase of matter.

Nutariel meets Adiabram (Adiabatic Theorem). Adiabram changes his system slowly compared with ħ/ΔE, and it stays in its eigenstate. Nutariel is driven on resonance, so her state does flop between levels. Whether a system changes state depends on how fast and at what frequency the push comes.

Wear the lore


Concept keywords: Rabi Oscillation, Nutariel, Quantum Foundations, physics lore, Pixelated Physics