ELFT HÍRADÓ

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

Meghívó

BME Elméleti Fizika Szeminárium,

máj. 16 péntek 10h15,
1111 Bp., Budafoki út 8., BME FIII. magasföldszint 1, szemináriumi szoba

Rakovszky Tibor (BME Elm. Fiz.):
Topological Quantum Spin Glass Order and its realization in qLDPC codes

Ordered phases of matter have close connections to computation. Two
prominent examples are spin glass order, with wide-ranging applications in
machine learning and optimization, and topological order, closely related
to quantum error correction. In this talk, I will introduce the concept of
topological quantum spin glass (TQSG) order [1] which marries these two
notions, exhibiting both the complex energy landscapes typical of many spin
glasses, and the quantum memory and long-range entanglement characteristic
of topologically ordered systems. Using techniques from coding theory and a
quantum generalization of Gibbs state decompositions, we show that TQSG
order is realized at low-temperatures in various quantum error correcting
codes, namely so-called low density parity check (LDPC) codes on expander
graphs. This extends previous results on the connection between classical
LDPC codes and spin glasses to the quantum realm.

[1] B Placke, T Rakovszky, NP Breuckmann, V Khemani: "Topological Quantum
Spin Glass Order and its realization in qLDPC codes", arXiv 2412.13248

Minden érdeklődőt szeretettel várunk.
Asbóth János,
 szemináriumi koordinátor