Experimental Realization of Optimal Time-Reversal on an Atom Chip for Quantum Undo Operations

Year: 2022

Authors: Mastroserio I., Gherardini S., Lovecchio C., Calarco T., Montangero S., Cataliotti F.S., Caruso F.

Autors Affiliation: Dipartimento di Fisica e Astronomia, Universita di Firenze, via Sansone 1, Sesto Fiorentino, I-50019, Italy; LENS, Universita di Firenze, via Nello Carrara 1, Sesto Fiorentino, I-50019, Italy; Dipartimento di Fisica “Ettore Pancini”, Universita degli Studi di Napoli Federico II, via Cinthia 21, Napoli, I-80126, Italy; Istituto Nazionale di Ottica (CNR-INO), Area Science Park, Basovizza, Trieste, I-34149, Italy; Forschungszentrum Julich, Peter Grunberg Inst PGI 8, Wilhelm Johnen Str, D-52428 Julich, Germany; Dipartimento di Fisica e Astronomia “G. Galilei” & Padua Quantum Technologies Research Center, Universita di Padova, Via Francesco Marzolo 8, Padova, I-35131, Italy; Istituto Nazionale di Fisica Nucleare (INFN), Sezione di Padova, Via Francesco Marzolo 8, Padova, I-35131, Italy; Istituto Nazionale di Ottica (CNR-INO), Largo Enrico Fermi 6, Firenze, I-50125, Italy

Abstract: The authors report the use of the dressed chopped random basis optimal control algorithm to realize time-reversal procedures. The latter are aimed for the implementation of quantum undo operations in quantum technology contexts as quantum computing and quantum communications. The last performed operation can be time-reversed via the undo command so as to perfectly restore a condition in which any new operation, chosen by the external user, can be applied. By generalizing this concept, the undo command can also allow for the reversing of a quantum operation in a generic time instant of the past. Here, thanks to optimal time-reversal routines, all these functionalities are experimentally implemented on the fivefold (Formula presented.) Hilbert space of a Bose-Einstein condensate of non-interacting Rb atoms in the ground state, realized with an atom chip. Each time-reversal transformation is attained by designing an optimal modulated radio frequency field, achieving on average an accuracy of around 92% in any performed test. The experimental results are accompanied by a thermodynamic interpretation based on the Loschmidt echo. These findings are expected to promote the implementation of time-reversal operations in a real scenario of gate-based quantum computing with a more complex structure than the five-level system considered here.


Volume: 5 (12)      Pages from:   to:

More Information: The authors thank Francesco Scazza for useful and insightful comments. F.C. was financially supported by the European Union´s Horizon 2020 research and innovation programme under FET-OPEN Grant Agreement No. 828946 (PATHOS). S.G. also acknowledges The Blanceflor Foundation for financial support through the project “The theRmodynamics behInd thE meaSuremenT postulate of quantummEchanics (TRIESTE)”. S.M. acknowledges support from the Horizon2020 program QuantERA ERA-NET Cofund in Quantum Technologies project T-NISQ, the Italian PRIN2017, and Fondazione CARIPARO, the BMBF project QRydDemo, and the INFN project QUANTUM. Open access funding provided by Universita degli Studi di Firenze within the CRUI-CARE Agreement.
KeyWords: Optimal control, Atom chip, Quantum undo operations, Entropy rectification, Time-reversal
DOI: 10.1002/qute.202200057