Joint ICTP/SISSA Condensed Matter Seminar, 18 May at 14:00, Khadijeh Najafi

[CMSP Seminars Secretariat]

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  Joint ICTP/SISSA Condensed Matter Seminar
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** * * Thursday**, 18 May 2023, 14:00*****(CET)** * **
In person: *Luigi Stasi Seminar Room **(Leonardo Building, second floor)***
**
/Zoom: 
https://zoom.us/meeting/register/tJUkdu2qrDoiHNCqrg_09BiB97PgPalbUfWx/<https://zoom.us/meeting/register/tJIsfuuhqjsrE9EZY2loNxNobg8Lf39NUVHJ>

Speaker: *Khadijeh Najafi *(IBM Quantum)

Title: *Detecting central charge in a superconducting quantum processor
*

Abstract:

Physical systems at the continuous phase transition point exhibit 
conformal symmetry rendering local scaling invariance. In two 
dimensions, the conformal group possesses infinite generators described 
by Virasoro algebra with an essential parameter known as a central 
charge. While the central charge manifests itself in a variety of 
quantities, its detection in experimental setup remains elusive.

In this work, we utilize Shannon-Renyi entropy on a local basis of a 
one-dimensional quantum spin chain at a critical point. We first use a 
simulated variational quantum eigen solver to prepare the ground state 
of the critical transfer field Ising model and XXZ model with open and 
periodic boundary conditions and perform local Pauli X and Z basis 
measurements. Using error mitigation such as probabilistic error 
cancellation, we extract an estimation of the local Pauli observables 
needed to determine the Shannon-Renyi entropy with respect to subsystem 
size. Finally, we obtain the central charge in the sub-leading term of 
Shannon-Renyi entropy.