🎯🤖 Piccolo

Piccolo.jl

Piccolo.jl is a Julia package for quantum optimal control. It finds control pulses that implement quantum operations — gates, state transfers, and open-system dynamics — by solving a trajectory optimization problem over the joint space of quantum states and drive amplitudes.

What you can do

• Synthesize gates or state transfers on qubits, qudits, cavities, and composite systems
• Model common hardware out of the box: transmons, transmon–cavity systems, trapped-ion chains, Rydberg arrays, and cat qubits
• Choose a pulse parameterization: piecewise constant, linear or cubic spline, Gaussian/erf envelopes, or custom functions
• Optimize gate duration (free-time), global phases (free-phase), and system parameters jointly with the pulse
• Suppress leakage via explicit costs and constraints on population outside the computational subspace
• Design robust pulses by optimizing fidelity over an ensemble of parameter variations
• Handle open systems with Lindbladian dynamics and density matrix objectives

Piccolo uses unitarity-preserving integrators and IPOPT as its NLP solver, and is part of the Harmoniqs ecosystem.