Synthesizing Compound Pulse Gadgets for Hamiltonian Simulation on Trapped-Ion Platforms

2026-07-01Hardware Architecture

Hardware ArchitectureEmerging Technologies
AI summary

The authors explain that usual methods for running quantum algorithms on trapped-ion devices make the process slow and noisy because they break operations into many small steps. They propose a new way to create continuous control pulses that combine these steps into bigger chunks, reducing the total time needed. Using a molecule simulation as an example, they show that their approach can run algorithms faster and with less delay in control commands. This could help quantum computers run more complex tasks before decoherence ruins the information.

Quantum Singular Value TransformationQSVTHamiltonian SimulationTrapped-ion Quantum ComputingGradient Ascent Pulse Engineering (GRAPE)Pulse SynthesisLindblad Master EquationDecoherenceBlock-encodingQuantum Control
Authors
Ria Patel, Masoud Hakimi Heris, Yuan Liu, Frank Mueller
Abstract
Standard gate-level transpilation introduces significant physical noise and overhead for high-precision quantum algorithms, such as the Quantum Singular Value Transformation (QSVT), on near-term trapped-ion hardware. Current compilers treat quantum operations as discrete units, forcing the physical control layer to execute highly fragmented laser pulses. To address this hardware-software disconnect, this work introduces a holistic pulse synthesis strategy that bypasses discrete gate-stitching to compile algorithms directly into continuous compound pulse gadgets. As a proof-of-concept, we target Hamiltonian simulation of the $H_2$ molecule, block-encoding the problem into a QSVT circuit to approximate the time-evolution operator $U = e^{-i H t}$ across 3 computational ions (2 system, 1 ancilla). We utilize the Gradient Ascent Pulse Engineering (GRAPE) algorithm to generate these compound gadgets and evaluate our methodology using noisy Lindblad master equation simulations. Preliminary observations indicate that the proposed strategy achieves significant temporal compression, reducing the total pulse schedule duration compared to standard compilers. Furthermore, synthesizing operations holistically eliminates the control-layer latency associated with discrete pulse lookup overhead. By streamlining the physical control schedule, this methodology offers a promising pathway to execute operations faster, highlighting the potential for compound gadgets to increase the computational depth achievable within fundamental $T_2$ decoherence limits.