Muzzle the Shuttle: Efficient Compilation for Multi-Trap Trapped-Ion Quantum Computers

Trapped-ion systems can have a limited number of ions (qubits) in a single trap. Increasing the qubit count to run meaningful quantum algorithms would require multiple traps where ions need to shuttle between traps to communicate. The existing compiler has several limitations which result in a high number of shuttle operations and degraded fidelity. In this paper, we target this gap and propose compiler optimizations to reduce the number of shuttles. Our technique achieves a maximum reduction of $51.17\mathrm{\%}$ in shuttles (average $\approx 33\mathrm{\%}$) tested over $125$ circuits. Furthermore, the improved compilation enhances the program fidelity up to $22.68$X with a modest increase in the compilation time.