2021
Programming the full stack of an open-access quantum computer
Virginia Frey, Richard Rademacher, Elijah Durso-Sabina, Noah Greenberg, Nikolay Videnov, Matthew L. Day, Rajibul Islam, Crystal Senko
IEEE International Conference on Quantum Computing and Engineering         arXiv:2106.06549
This manuscript describes the full stack programming of QuantumION, an open-access, remote-controlled, trapped-ion quantum information processor for the research community, currently being developed at Waterloo. QuantumION is a joint initiative with Prof. Crystal Senko’s research group and funded by Canada First Research Excellence Fund (CFREF).
Abstract: We present a new quantum programming language called ‘Quala’ that enables true full-stack programming of quantum hardware. Quala allows seamless integration of abstraction layers such as the digital circuit layer and the analog control pulse waveform layer. Additionally, the language supports user-issued low-level hardware instructions like FPGA actions. Mid-circuit measurements and branching decision logic support real-time, adaptive programs. This flexibility allows users to write code for everything from quantum error correction to analog quantum simulation. The combination of a user-facing calibration database and a powerful symbolic algebra framework provides users with an unprecedented level of expressiveness and transparency. We display the salient characteristics of the language structure and describe how the accompanying compiler can translate programs written in any abstraction layer into precisely timed hardware commands. We intend for this language to bridge the gap between circuit-level programming and physical operations on real hardware while maintaining full transparency in each level of the stack. This eliminates the need for “behind-the-scenes” compilation and provides users with insights into the day-to-day calibration routines.