Project 2: “Hello Quantum” (Framework Basics)

Build small quantum circuits in a framework and validate results.


Project Overview

Attribute Value
Difficulty Level 1: Beginner
Time Estimate Weekend
Main Language Python
Alternative Languages Q#, Java
Knowledge Area Quantum circuits
Tools Qiskit or Cirq
Main Book “Quantum Computation and Quantum Information” by Nielsen & Chuang

What you’ll build: A set of small circuits (superposition, entanglement) and measurement experiments.

Why it teaches quantum: Frameworks hide math but still require correct conceptual wiring.

Core challenges you’ll face:

  • Building circuits with correct gate order
  • Measuring and interpreting results
  • Understanding sampling noise

Real World Outcome

You will run circuits and see histograms matching expected probabilities.

Example Output:

$ python hello_quantum.py --circuit bell
Counts: 00=512, 11=512

Verification steps:

  • Verify superposition yields 50/50 outcomes
  • Verify Bell state yields correlated outcomes

The Core Question You’re Answering

“How do I translate quantum concepts into working circuits?”

This is the bridge from theory to practice.


Concepts You Must Understand First

Stop and research these before coding:

  1. Quantum circuits
    • How does gate order affect outcomes?
    • Book Reference: Nielsen & Chuang, Ch. 4
  2. Entanglement
    • Why do Bell states show perfect correlation?
    • Book Reference: Nielsen & Chuang, Ch. 2
  3. Sampling noise
    • Why do results fluctuate with small shot counts?
    • Book Reference: “Quantum Computing: An Applied Approach” by Jack Hidary, Ch. 3

Questions to Guide Your Design

  1. Circuit selection
    • Which minimal circuits show key behaviors?
    • How will you parameterize them?
  2. Measurement analysis
    • How many shots will you run?
    • Will you compute confidence intervals?

Thinking Exercise

Bell Circuit

Write the gate sequence for producing a Bell state from 00>.

Questions while working:

  • Which qubit is the control?
  • What measurement outcomes should appear?

The Interview Questions They’ll Ask

Prepare to answer these:

  1. “What is a quantum circuit model?”
  2. “How do you create entanglement?”
  3. “Why do repeated runs give different results?”
  4. “What is a measurement shot?”
  5. “How do you verify a circuit is correct?”

Hints in Layers

Hint 1: Starting Point Start with a single-qubit Hadamard.

Hint 2: Next Level Add a CNOT to create a Bell state.

Hint 3: Technical Details Use a simulator backend before running on hardware.

Hint 4: Tools/Debugging Plot histograms of measurement counts.


Books That Will Help

Topic Book Chapter
Circuits Nielsen & Chuang Ch. 4
Entanglement Nielsen & Chuang Ch. 2
Sampling “Quantum Computing: An Applied Approach” by Jack Hidary Ch. 3

Implementation Hints

  • Keep circuit sizes small.
  • Compare simulator results to analytic probabilities.
  • Use fixed seeds for reproducible tests.

Learning Milestones

  1. First milestone: You can build and run simple circuits.
  2. Second milestone: You can create entanglement and verify correlations.
  3. Final milestone: You can interpret measurement histograms correctly.