SpIn-orbitronic QuAntum bits in Reconfigurable 2D-Oxides

Project Information

IQARO

Grant agreement ID: 101115190

DOI

10.3030/101115190

EC signature date 31 July 2023

Start date 1 October 2023

End date 30 September 2027

Funded under

• The European Innovation Council (EIC)

Total cost

€ 3 717 545,25

EU contribution

€ 3 717 545,25

Coordinated by

CONSIGLIO NAZIONALE DELLE RICERCHE
Italy

Periodic Reporting for period 1 - IQARO (SpIn-orbitronic QuAntum bits in Reconfigurable 2D-Oxides)

Reporting period: 2023-10-01 to 2024-09-30

Summary of the context and overall objectives of the project

Qubits, the units of information in quantum computers, are made of quantum systems like electrons or photons. Like classical bits, they must have two distinct states which can be manipulated without losing quantum coherence. Realising the tremendous potential of quantum computing requires scaling up the number of qubits while maintaining control over their properties, a highly challenging goal. The EIC-funded IQARO project has introduced a new quantum system in this framework by developing spin-orbitronics qubits in oxides. The spin-degrees of freedom are manipulated with electric fields through the spin-momentum locking of the electrons, thus avoiding the need for complicated fabrication of on-chip micromagnet or the application of RF magnetic fields, and consenting the coupling of spins by photons, phonons or direct capacitive coupling. In the first year of the project, single and double quantum dots based on 2D electron gases formed at oxide interfaces have been realized as a basic starting point for qubits.
IQARO’s grand-challenge is the foundation of a novel quantum material platform for the development of fast, scalable qubits integrated with silicon-technology at wafer-scale size. We aim at realizing spin-orbit (SO) qubits surpassing state of art technologies and at demonstrating radically new quantum control methods based on the exceptional spin-orbitronics properties of oxide 2D-electron gases (2DEGs).

Work performed from the beginning of the project to the end of the period covered by the report and main results achieved so far

IQARO proposes a beyond state-of-the-art platform based on a novel quantum material for solid state qubits.
The specific activities performed in IQARO in the first reporting period are:
• Design and optimization of QDs at LAO/STO interface have been achieved by successful study of the electronic properties of the interface and effective growth of LAO/STO membranes. The study of the spin-flip dynamics and EDSR in the single and double QD also showed that one can optimize the parameters (size of the dot, confinement potential, AC external fields, distance between the dots) in such a way to initialize and read the state of the QD with a fidelity reaching the 99,6%.
• Growth control of epitaxial LAO on STO through techniques like PLD, monitored by RHEED and characterized by AFM, has been demonstrated. This control is crucial for achieving the desired interface quality. Finally, the growth of free-standing oxide-membranes (LAO/STO) by strained-induced spalling was achieved.

All the step above allow us to conclude that Milestone 1 on the design and optimization of the QD was accomplished. In the future, lithographic techniques will enable the fabrication of an oxide-based qubit. The next steps toward achieving quantum dots at the LAO/STO interfaces will be a significant milestone toward realizing quantum devices based on this system.

Progress beyond the state of the art and expected potential impact (including the socio-economic impact and the wider societal implications of the project so far)

The novelty of IQARO consists in:
• Validating a novel electric field -controlled SO-qubits platform characterized by a set of unique handles for novel quantum control paradigms, like spin-orbitronics methods of quantum control based on the large degree of electron’s spin-momentum locking of this system.
• Promoting novel schemes of driving exchange interactions based on quantum control to speed gate operations;
• Exploiting novel functionalities of oxide interfaces to perform initialization and read-out of a single spin quantum dot using spin-charge conversion.
IQARO complies with the expected outcomes of the call EIC pathfinder challenge: Alternative approaches to quantum information processing, communication and sensing by exploiting a novel information processing technology platform and by pushing synergetic collaboration with existing European platforms, infrastructures, and innovation eco-system in quantum technology. The innovative qubit technology explored in IQARO allows a change in paradigm compared to current qubit platforms, offering wide-reaching impacts on Europe’s economy and science beyond the already vast fields of application for Quantum information.
IQARO will set out a credible pathway to further develop quantum technologies and their applications in the areas of quantum information, in order to strengthen European technical sovereignty in this strategic field and achieve first-mover industry leadership.

IQARO PATH TOWARDS THE SPIN-ORBIT QUBIT