# How a phase becomes 011

## 00–08 seconds

The target carries an eigenphase

Assume an exact eigenstate with eigenvalue exp(2 pi i theta), where theta is 3/8.

## 08–16 seconds

Three counting qubits hold the pattern

Controlled powers create a phase pattern across the eight counting-register states.

## 16–24 seconds

The inverse Fourier transform reads it

Because 3/8 has an exact three-bit representation, the ideal output is integer 3.

## 24–32 seconds

Declare the displayed bit order

Most-significant bit first: 011 means 0/2 + 1/4 + 1/8 = 3/8.

## 32–40 seconds

Other phases need more care

Off-grid phases give a probability distribution with periodic tails. This exact result is a special case.

## 40–48 seconds

Check the resources too

State preparation and controlled powers matter. Read the complete model and its bit-order convention.