P04 - Quantum Information Protocols with Limited Resources

Ignacio Cirac


After many years of intensive research, it is now possible to control and manipulate tens of qubits with high precision. This has been achieved with trapped ions, cold atoms, superconductors, and photons, and it is very likely that other technologies will soon catch up. Even though a full-fledged quantum computer is still very far in time, it is expected that in the next few years quantum processors composed of up to hundred qubits will be available, and that one will be able to reliably perform more than thousand quantum gates without having to resort to error correction schemes. Under these conditions, can we take advantage of those small systems? And, what can we learn?

The long-term goals and visions of this project are to: (i) develop applications and protocols which can be carried out with small quantum processors, and that outperform existing and planned classical devices; (ii) use quantum systems to learn few/many-body quantum phenomena; (iii) Revisit classical algorithms and protocols inspired by quantum devices; (iv) bridge the gap between abstract results and specific experimental setups.

PI Ignacio Cirac on
Quantum Information Protocols with Limited Resources


Subproject Leader: Ignacio Cirac

PostDoc: Flavio Baccari

PhDs: Esther Cruz

Master: Benjamin Schiffer

Admins: Eileen Welz, Elena Wiggert





The quantum marginal problem for symmetric states: applications to variational optimization, nonlocality and self-testing
A. Aloy, M. Fadel, J. Tura
Preprint (2020)

Algorithms for quantum simulation at finite energies
S. Lu, M. Carmen Bañuls, J. I. Cirac
Preprint (2020)

Entanglement marginal problems
M. Navascues, F. Baccari, A. Acin
Preprint (2020)

Ultrafast molecular dynamics in terahertz-STM experiments: Theoretical analysis using Anderson-Holstein model
T. Shi, J. I. Cirac, E. Demler
Phys. Rev. Research 2, 033379 (2020)

A variational approach for many-body systems at finite temperature
T. Shi, E. Demler, J. I. Cirac
Phys. Rev. Lett. 125, 180602 (2020)

Generation of Photonic Matrix Product States with a Rydberg-Blockaded Atomic Array
Z. Wei, D. Malz, A. González-Tudela, J. I. Cirac
preprint (2020)

Device-Independent Certification of Genuinely Entangled Subspaces
F. Baccari, R. Augusiak, I. Šupić, Antonio Acín
Phys. Rev. Lett. 125, 260507 (2020)

Bounding sets of sequential quantum correlations and device-independent randomness certification
J. Bowles, F. Baccari, A. Salavrakos
Quantum 4, 344 (2020)

Matrix Product States: Entanglement, symmetries, and state transformations
D. Sauerwein, A. Molnar, J. I. Cirac, B. Kraus
Physical Review Letters 123, 170504 (2019)