Skip to content
Preprint

The logical set of Gaussian states under the stabilizer subsystem decomposition

Sep 2026 · 0 citations · 10 references
Physics

Abstract

Universal quantum computation requires non-Gaussianity in continuous-variable systems and non-stabilizerness in discrete-variable systems. Yet, mapping a Gaussian state into the Gottesman-Kitaev-Preskill logical subspace can yield a logical qubit with non-stabilizer resources. To understand how the continuous-variable structure determines logical resources, we characterize the image of single-mode Gaussian states under the corresponding extraction channel, known as the stabilizer subsystem decomposition. Specifically, we derive series expressions for the logical Bloch vector and characterize the resulting reachable set, enabling an analytical treatment of the robustness of magic of the logical states. We then turn this geometric framework into a certification tool: by mapping a discrete-variable qubit witness to a continuous-variable squeezing witness, we obtain lower bounds on the squeezing of prepared states. We also show that ensembles of Gaussian states can violate both stabilizer and classical bounds. Violation of the stabilizer bound certifies the relational resource known as"set-magic,"while violation of the classical bound enables the certification of cryptographic randomness at moderate squeezing.

View source

Similar papers

Preprint Sep 2026

Causal inequalities witness non-stabilizerness

Stabilizer operations describe a fragment of quantum theory that is known to be efficiently classically simulable, thanks to the Gottesman-Knill theorem. For this reason, nonstabilizer resources such as magic states are necessary for universal quantum computation. Interestingly, the operational and axiomatic approaches...

Leonardo Vaglini, Nasra Daher Ahmed, Ravi Kunjwal · 0 citations
Preprint Aug 2026

Universal magic state concentration

Magic plays a dual role in quantum computation: it promotes stabilizer dynamics from efficient classical simulability to computational universality, but also challenges fault-tolerant architectures, since non-stabilizer operations are harder to protect against noise. Magic state distillation addresses this issue, yet e...

Jacopo Rizzo, Lorenzo Leone · 1 citation
Preprint Sep 2026

Certifying fermionic Gaussian states (and a little more) with optimal precision dependence

Fermionic Gaussian states are the workhorse reference states for qubit-based quantum simulation of fermionic systems, yet existing certification protocols either proceed via fidelity estimation, leading to suboptimal sample complexity in the target precision $\epsilon$, only apply to Haar-typical states, or require ada...

Ninnat Dangniam, Laphas Premcharoen, Metrasit Sripech et al. · 0 citations
Preprint Aug 2026

Stabilizer Statistical Mechanics: A Framework for Efficient Quantification and Classification of Magic States

The partition function is statistical mechanics'answer to an exponentially large spectrum, distilling it into a single analytic object whose temperature dependence resolves the full structure of the underlying ensemble. We show that magic, the resource separating universal quantum computation from classically simulable...

William E. Salazar, G. Saxena, Jack S Baker et al. · 3 citations · ⚡1
Preprint Aug 2026

Probing quantumness of superpositions of Gaussian states via Tsirelson probability

Quantifying nonclassicality in continuous-variable systems remains a fundamental problem in quantum information science. The Tsirelson probability, central to the Tsirelson precession protocol, is defined as the average probability that a precessing quadrature yields a positive outcome when measured at $K$ equally spac...

Yue Zhang · 0 citations
Preprint Oct 2026

Avoiding Exponentially Large Groups with Open Quantum System Technology

We propose a novel approach to state preparation by embracing the full power of open quantum systems. Instead of working with the whole unitary group in $n$ qubits, we identify a small Lie group $G$ in $(n+3)$ qubits. The dimension of its Lie algebra is $\text{poly}(n)$. Every state can be approximated starting from an...

Ji-Hong Cai, Advith Govindarajan, M. Junge · 0 citations

We use cookies to run the site and, with your consent, for analytics and to show ads. See our Cookie Policy.