Take and . The orbit of modulo is , so the order is . The bit length of is , and…
PHYSICS · Multi-part · Fermi University Physics · Quantum Information & Technology · The quantum circuit model and quantum algorithms · The quantum circuit model and quantum algorithms
Quantum Information and Technology, Ch Order finding and Shor's factoring algorithm
Problem
Take N=5 and a=2. The orbit of 2 modulo 5 is 2,4,3,1, so the order is r=4. The bit length of N is L=⌈log25⌉=3, and order finding is run with the register size t=2L+1=7 control qubits (no extra qubits for the error tolerance).
((a)) State the size of the measured output register, 2t.
((b)) Since r divides 2t exactly, list every possible measured value of the output register and its probability.