SAMOP 2023 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
Q: Fachverband Quantenoptik und Photonik
Q 8: QI Poster I (joint session QI/Q)
Q 8.31: Poster
Monday, March 6, 2023, 16:30–19:00, Empore Lichthof
Programmable cooling on noisy quantum computers: Implementation and error analysis — •Imane El Achchi1, Anne Matthies1, Achim Rosch1, Mark Rudner2, and Erez Berg3 — 1Institute for Theoretical Physics, University of Cologne, 50937 Cologne, Germany — 2University of Washington, Seattle, WA 98195-1560, US — 3Weizmann Institute of Science, Rehovot, 76100, Israel
Recent advances in quantum computing provide a vast playground for the application of quantum algorithms on noisy intermediate-scale quantum devices. Here, we test the performance of the programmable adiabatic demagnetization protocol proposed in Ref. [1] on IBM’s quantum devices. The cooling protocol prepares low-energy states for any gapped Hamiltonian independently of the system’s initial state. Half the qubits simulate the system, and the other a bath in a strong Zeeman field, initialized in the polarized state. Entropy is transferred from the system to the bath by slowly decreasing the Zeeman field. Finally, the bath spins are measured and reset to the polarized state. The process is repeated throughout the protocol until a low-energy state of the system is reached. Cooling protocols are generally stable against low noise, making them a promising application for near-term quantum computers. We experimentally observe a cooling effect for the available small system size and limited gate depth on the IBM quantum device using quantum optimal control. Furthermore, we analytically analyze the dynamics of the cooling protocol to find a dark state of the corresponding quantum channel.
[1] arxiv: 2210.17256