Matthias Rosenkranz

Decoded Quantum Interferometry (DQI) without Dicke state preparation. My latest paper is out
arxiv.org/abs/2601.15171
scirate.com/arxiv/2601.1...

Superconducting pairing correlations on a trapped-ion quantum computer The Fermi-Hubbard model is the starting point for the simulation of many strongly correlated materials, including high-temperature superconductors, whose modelling is a key motivation for the construc...

The eagle-eyed will have spotted the first Helios experiments last week - run by my colleagues and our external partners.

arxiv.org/abs/2511.02125
arxiv.org/abs/2511.03686
arxiv.org/abs/2511.03689

Helios: A 98-qubit trapped-ion quantum computer We report on Quantinuum Helios, a 98-qubit trapped-ion quantum processor based on the quantum charge-coupled device (QCCD) architecture. Helios features $^{137}$Ba$^{+}$ hyperfine qubits, all-to-all c...

Our new quantum computer Helios is out. Take a look at this paper for technical details of its design, operations, and benchmarks.

arxiv.org/abs/2511.05465

To be fair, the DQI paper didn't claim an advantage for Maxcut but suggested one for a different problem

Our paper elucidating resources required for quantum Gibbs state preparation via Lindblad simulation is now published in @quantum-journal.bsky.social

quantum-journal.org/papers/q-202...

Built for All: Introducing Our New Software Stack Our next-generation quantum computer, Helios, will come online this year as more than a new chip. It will arrive as a full-stack platform that sets a new standard for the industry.

🧵 1/? Today #quantinuum announced Guppy, the new programming language my team has been developing, and Selene the new simulator that goes with it. This is the software stack that supports our new Helios #quantum computer, and it successors. #quantumcomputing

www.quantinuum.com/blog/built-f...

Our latest paper is out. In a joint work with Marcello Benedetti and Matthias Rosenkranz ( @mrosenkranz.bsky.social ) , we present a new quantum algorithm for solving Lyapunov equations.
scirate.com/arxiv/2508.0...
arxiv.org/abs/2508.04689

We have an opening for a research scientist in the quantum algorithms team at Quantinuum. This is permanent in London or Cambridge, UK. Details: jobs.eu.lever.co/quantinuum/2...

Quantum Error-Corrected Computation of Molecular Energies We present the first demonstration of an end-to-end pipeline with quantum error correction (QEC) for a quantum computation of the electronic structure of molecular systems. Using Quantinuum H2-2, we c...

What's this? Some very nice work by my colleagues.
#quantinuum #quantumcomputing #ftqc #quantum
arxiv.org/abs/2505.09133

Happy that our paper on state preparation for multivariate functions is out in @quantum-journal.bsky.social. We've also open sourced the code. Give it a go in your algorithm: github.com/CQCL/mvsp

Digital quantum magnetism at the frontier of classical simulations The utility of near-term quantum computers for simulating realistic quantum systems hinges on the stability of digital quantum matter--realized when discrete quantum gates approximate continuous time ...

Hi #quantum bluesky 👋 In arxiv.org/abs/2503.20870 with #Quantinuum, Fermioniq, Caltech, EPFL, TUM we show Quantinuum's H2 ion-trap #quantumcomputer can simulate dynamical evolution of a 2D Ising model at late times and sizes pushing beyond classical means(MPS, PEPS, sparse Pauli propagation, NN).

Here's one from our algorithms team and QuSoft/CWI

If you’re running randomized benchmarking on your quantum computer, stop and read our paper!

arxiv.org/pdf/2502.00154

The deadline for talk submissions at QCTiP 2025 is coming up! Consider submitting a talk until January 10.

We see this is a step towards implementing recent quantum Gibbs sampling algorithms on quantum hardware.

Many thanks for the fantastic work to my co-authors Eric Brunner, Luuk Coopmans, Gabriel Matos, Fred Sauvage and Yuta Kikuchi, all @quantinuum.bsky.social

Finally, we analyse algorithmic errors by simulating the full quantum circuits. Circuit simulations with a noise model confirm the trade-off between algorithmic errors and noise, whereby a larger Trotter time step can lead to smaller overall error.

Then we analyse analytically and numerically convergence, mixing time, spectral gap etc. for a mixed-field Ising model and random k-local Pauli jump operators. We also find a certain noise resilience of the protocol at relevant error rates

We propose a simplified Lindblad simulation algorithm combining various earlier ideas, e.g. the Chen et al. quantum thermal state preparation algorithm, QDrift-like randomized jump operators, a single-ancilla protocol for the dissipative term, ETH for good convergence and simpler coherent term etc.

Lindblad engineering for quantum Gibbs state preparation under the eigenstate thermalization hypothesis Building upon recent progress in Lindblad engineering for quantum Gibbs state preparation algorithms, we propose a simplified protocol that is shown to be efficient under the eigenstate thermalization...

Very happy that our new paper on quantum Gibbs state preparation is out today 🎅

scirate.com/arxiv/2412.1...

We hope this bridges the gap between the recent theoretical advances in Lindblad simulation algorithms for quantum Gibbs sampling and their eventual quantum hardware implementation.

Interesting question by Mark Wilde on Twitter:
There have been many breakthrough algorithms for thermal state preparation recently. Does any of them prepare a canonical purification of a thermal state? i.e, the following state
(\sqrt{e^{-H}/Z} ⊗ I) ∑_i |i⟩ ⊗ |i⟩
with |i⟩ = computational basis

Overlooking a snow-covered landscape with white mountains in the background and Tibetan prayer flags on a pole in the foreground

Key Gompa (monastery) against a mountain backdrop

Stupas at Tabo monastery

A turquoise Spiti river running through a valley with shrubs on the left and snow-capped mountains in the distance

I would include Spiti Valley (Himachal Pradesh, India).

Besides the spectacular landscape, places like Tabo Monastery hold beautiful frescoes some of which date to ~1000 CE

Submissions for QCTiP 2025 are now open.

Thank you

Optimization by Decoded Quantum Interferometry We introduce Decoded Quantum Interferometry (DQI), a quantum algorithm for reducing classical optimization problems to classical decoding problems by exploiting structure in the Fourier spectrum of th...

it will be interesting to see whether this "classical attack" gives anything for the "optimization by decoded quantum interferometry" paper
arxiv.org/abs/2408.08292

The plot thickens:
"While all the proofs in the paper are correct to the best of our knowledge, we have been recently informed about a classical attack on our polynomial system."

Yes please.

Pure statesman

So close! Somebody please post something really good 🙏

Happy No arXiv Announcements Day to those who celebrate