A Compilation Framework for Quantum Simulation of Non-unitary Dynamics
This work addresses the problem of efficient compilation for open-system quantum simulation, which is important for quantum computing applications involving noise and dissipation.
The paper presents a compilation framework for quantum simulation of non-unitary dynamics, treating quantum channels as first-class objects. The optimized pipeline reduces gate count by up to 99% over an unoptimized baseline and scales better than circuit-first Stinespring compilation.
Most quantum compilers assume programs are reversible unitary circuits. This fits closed-system algorithms, but not open-system simulation, where the natural program objects are quantum channels describing non-unitary dynamics. We present a channel-first compilation framework that treats channels as first-class compilation objects. Our core IR, ChannelIR, represents channels explicitly in Kraus form, a standard channel representation, with Pauli-sum structure, enabling algebraic rewrites before circuit synthesis. We instantiate the framework with LindFront, a frontend that lowers continuous-time Lindbladian generators to short-time channels, and a backend that compiles these channels to executable circuits with structure-aware optimizations. On Lindbladian and channel-simulation benchmarks, the optimized pipeline reduces gate count by up to 99% over an unoptimized channel-first baseline and scales better than circuit-first Stinespring compilation.