ELFT HÍRADÓ

[Janos Asboth <asboth.janos AT ttk.bme.hu>]

Meghívó

BME Elméleti Fizika Szeminárium,

nov. 28. péntek 10h15,

1111 Budapest, Budafoki út 8., BME F III. magasföldszint 01.,
Elméleti Fizika Tanszék szemináriumi szoba

Szombathy Dominik (BME TTK Elméleti Fizika Tanszék):
Magic and Complexity in Quantum Circuits (PhD házi védés)

My doctoral research examines the mechanisms that generate quantum
resources, which are important in realising quantum computational
advantage, with a particular focus on non-stabilizerness, which
characterises resources beyond entanglement.

While Clifford circuits efficiently generate entanglement, they remain
classically simulable. However, the introduction of non-Clifford
operations, like the T-gate, leads to a rapid transition in both spectral
statistics and resource generation. My dissertation systematically examines
how periodic orbit structures and spectral degeneracies in pure Clifford
circuits are progressively disrupted by the presence of non-Clifford gates.
This T-gate doping eventually leads to chaotic behaviour exponentially
fast, and in the form of reproducing random unitary statistics, universal
quantum computation. A transition can also be seen for the
non-stabilizerness statistics, while only reaching random unitary behaviour
linearly.

Non-stabilizerness or magic quantifies non-Cliffordness, or in other words,
how far a state lies from a stabiliser state. In random unitary circuits,
we quantify how magic and entanglement are generated, and while their mean
values correlate, fluctuations of these resources are asymptotically
independent. This work also extends the investigation of stabiliser Rényi
entropy in open quantum systems under noise channels. Showing that
non-trivial stabiliser Rényi entropy can emerge as a result of
environmental noise.

Link to PhD thesis and thesis points:
https://drive.google.com/drive/folders/1h5BNz_ItbCcVpjF5QFXwLMnCZ2nH5mxq?usp=sharing

Minden érdeklődőt szeretettel várunk.
Asbóth János,
 szemináriumi koordinátor