IQM Quantum Computers to showcase latest quantum research at APS March Meeting 2023

This year at the APS March Meeting in Las Vegas, United States, IQM Quantum Computers will share its latest quantum research with a global audience of physicists, scientists, and students, both in person from March 5–10 and online from March 20–22.

More than 15 scientists and quantum engineers from the company will present talks ranging from the unimon qubit, the long-distance transmon coupler with CZ gate fidelity above 99.8%, to the design of superconducting quantum circuits for simulations of nanoscale-NMR systems, and more.

In addition, IQM has lined up an interactive agenda, including virtual reality, chip demos, ask-me-anything sessions, one-on-one meetings, and happy hour, to connect with a cross-section of stakeholders.

The annual meeting organised by the American Physical Society (APS) has been one of the most important conferences on IQM’s events calendar. The meeting is expected to bring together a diverse international community of over 10,000 experts.

Image: IQM Team at last year's APS March Meeting 2022

“This is my first time attending the APS March Meeting, and I am excited to share the most recent results from our recently published paper, “Long Distance Transmon Coupler with CZ gate Fidelity above 99.8%,” with other groups and companies. Participants should expect a thorough deep dive into the qubit designs at IQM and an in-depth understanding of the analysis of our high-fidelity CZ gates,” said Quantum Engineer Fabian Marxer.

Year after year, the APS March Meeting excites Juha Vartiainen, the Chief Operating Officer and Co-founder at IQM Quantum Computers. “It's an annual update with the brightest minds from the scientific community. This year I am looking forward to discussions on processors and fabrication, control electronics, partnerships, and collaboration.”

As a Product Manager, Jorge Santos sees APS March Meeting as an important industry event, adding: “It also allows me to contact a very wide audience working on other topics, enabling me to identify possible synergies with other industries and academic fields and recognise new potential use cases for our technology.”

For Manuel Algaba, a Quantum Algorithm Engineer, presenting at APS March is such an interesting opportunity that he looks forward to sharing IQM’s latest scientific work with academia, industry, and everyone involved in making use of quantum.

“Our new fermion-to-qubit mapping, together with the compression technique we developed, paves the way to achieving quantum simulations of interesting materials using quantum computers. People usually do this by implementing a lot of small steps resembling the simulation you want to achieve. However, in the NISQ era, your qubits are very likely to have lost all their quantum behaviour after a couple of steps. What we did is to reduce the size of these steps to the minimal one ever described for some interesting models, allowing for the implementation of more steps before the lifetime of the qubits is over.”

No matter whether you attend in person or virtually, keep reading some of the summaries to get a quick overview of each paper from IQM.

IQM at the APS March Meeting 2023:

Showcase Booth #831

Image: IQM booth at APS March Meeting 2023


Estimating the error budgets of quantum gates in superconducting qubits

Presenter: Miha Papič, Quantum Engineer

When: Monday, March 6, 11:42–11:54 AM (Room 406)

Abstract: We have constructed detailed noise models of the error mechanisms present in current quantum computing hardware based on superconducting circuits. We then use Bayesian learning to estimate the contributions of a number of noise sources to the errors of quantum gates in order to gain a better understanding about how to further improve current quantum computers.

Long-distance transmon coupler as a building block for quantum processors

Presenter: Antti Vepsalainen, Senior Quantum Engineer

When: Friday, March 10, 1:30–1:42 PM (Room 401/402)

Abstract: Tunable coupling of superconducting qubits has been widely studied due to its importance for isolated gate operations in extensible quantum processor architectures. Here, we demonstrate a tunable qubit-qubit coupler based on a floating transmon device which allows us to place qubits at least 2 mm apart from each other while maintaining over 50 MHz coupling between the coupler and the qubits. In the introduced tunable-coupler design, both the qubit-qubit and the qubit-coupler couplings are mediated by two waveguides instead of relying on direct capacitive couplings between the components, reducing the impact of the qubit-qubit distance on the couplings. This leaves space for each qubit to have an individual readout resonator and a Purcell filter needed for fast high-fidelity readout. In addition, simulations show that the large qubit-qubit distance reduces unwanted non-nearest neighbor coupling and allows multiple control lines to cross over the structure with minimal crosstalk.

Fabrication of uniform Manhattan-style transmon qubits on 150 mm wafers

Presenter: Liuqi Yu, Quantum Physicist

When: Thursday, March 9, 4:12–4:24 PM (Room 401/402)

Abstract: To scale up the number of qubits patterned onto a single wafer, the quantum processor rapidly increases in its footprint. To maintain the processor’s performance, a precise control over the frequencies of individual qubits is often of great importance. Highly coherent transmon qubits can be fabricated through angled depositions. The qubit frequency is directly associated with room temperature Josephson junction (JJ) resistance via Ambegaokar–Baratoff relation. When fabricating on large-scale wafer, since the evaporation source is point-like, the effective deposition angles are different for individual JJs depending on their positions on the wafer. It inevitably leads to varying JJ resistances even for the same designed JJ size. Consequently, it presents a challenging task to accurately allocate design qubit frequencies on a large-scale wafer. In this work, we fabricate identical Manhattan-style JJs across a 150 mm wafer to examine the spatial uniformity of their resistances. To compensate the variation of the deposition angle, the designed JJ sizes are individually adjusted according to their positions on the wafer. The room temperature resistance measurements show a variation in the resistance of about 10% across the wafer. The uniformity is further improved by local annealing of individual JJs post fabrication. The resultant standard deviation of the resistance is reduced to less than 1%, which is suitable for large scale qubit production.

You can also follow @meetIQM on Twitter and LinkedIn: for our updates during the event.


Michael Sarpong Bruce is a Communications Specialist at IQM. He has over ten years of experience in marketing and communications across diverse industries, including mining, telecommunications, and insurance. He is also a former business journalist and has experience in public relations and media buying agencies.