qstack

qstack is a framework for compiling and executing quantum programs using a stack-based approach for dynamic qubit allocation and measurement. It provides tools for defining quantum kernels, compiling them into lower-level instructions, integrating classical computations, and incorporating quantum error correction seamlessly.

Installation

To install qstack, run:

pip install .

Key Features

• Dynamic Qubit Allocation: Allocate and measure qubits dynamically using a stack-based approach, enabling flexible and modular program design.
• Quantum Kernels: Define quantum operations in a modular and nested manner, supporting complex quantum workflows.
• Classical Oracles: Integrate classical computations into quantum programs, allowing conditional logic and hybrid quantum-classical operations.
• Instruction Set Compilation: Compile high-level quantum instructions into hardware-specific low-level operations, ensuring compatibility with diverse quantum hardware.
• Quantum Error Correction: Leverage modularity to incorporate advanced quantum error correction techniques, such as the Steane code, into the compilation of programs. This ensures resilience against errors and supports fault-tolerant quantum computation.
• Independent QPU and CPU Interfaces: Demonstrates the independent operation of quantum and classical processors, showcasing their respective capabilities and interactions.

Usage

Explore the examples/ directory for sample usage of qstack. Some key examples include:

• bell.py: Demonstrates creating a Bell state.
• teleport.py: Implements quantum teleportation using entanglement and classical communication.
• noisy_bell.py: Simulates a Bell state with noise, introducing realistic quantum system modeling.
• steane.py: Demonstrates quantum error correction using the Steane code, showcasing fault-tolerant quantum computation.
• cpu.py: Highlights the independent operation of the classical processor (CPU) for handling classical logic and measurement results.
• qpu.py: Highlights the independent operation of the quantum processor (QPU) for executing quantum instructions.

Run an example using:

python examples/steane.py

High-Level Syntax Examples

qstack supports a high-level syntax for defining quantum programs. Here are a couple of examples:

Example 1: Bell State

allocate q1:
  h q1
  allocate q2:
    cx q1 q2
  measure
measure

Example 2: Quantum Teleportation

allocate q1:
  allocate q2:
    allocate q3:
      h q2
      cx q2 q3
      cx q1 q2
      h q1
    measure
  measure
  ?? apply_corrections(q1)
measure q3

Documentation

The core functionality of qstack is implemented under the src/qstack/ directory. Key modules include:

• compiler.py: Handles the compilation of quantum programs, including error correction.
• emulator.py: Simulates quantum program execution, supporting both noiseless and noisy environments.
• layer.py: Defines abstraction layers for quantum operations, such as the Toy and clifford_min layers.
• noise.py: Models noise in quantum computations, enabling realistic simulations.
• stack.py: Implements the stack-based qubit allocation and measurement, central to qstack's design.
• classic_processor.py and qpu.py: Define the independent interfaces for classical and quantum processors, respectively.

Refer to the source code for detailed implementation and extendability.

License

This project is licensed under the standard MIT License. See the LICENSE file for details.