Quantum Operations and Metrology with Entangled Electrons in a Penning Trap

Vladimir S. Malinovsky

Lucas Lamata, Diego Porras, J. I. Cirac +2 more

Entanglement of isolated elementary particles other than photons has not yet been achieved. We show how building blocks demonstrated with one trapped electron might be used to make a model system and method for entangling two electrons. Applications are then considered, including two-qubit gates and more precise quantum metrology protocols.

Tracy E. Northup, Andreas Stute, Bernardo Casabone +3 more

At the University of Sussex we are building a coplanar-waveguide (CPW) Penning trap. This is a novel planar Penning trap, which results form the projection of the well-known cylindrical trap onto the surface of a chip [1]. The trap allows for the compensation of electrical anharmonicities up to the sixth order and permits the observation of a single trapped electron, a primary goal not yet achieved with planar Penning trap technology. The electron can be coupled to a distant superconducting coplanar-waveguide resonator, such as those used in circuit-QED with artificial two level systems. The cyclotron motion interacts coherently with the microwave resonator, implementing a system of two coupled quantum harmonic oscillators and with applications in quantum metrology and quantum computation. In the poster, we report on recent experimental progress in the construction of a cryogenic CPW- Penning trap.

Sugam Kumar

Quantum computers have the potential to solve problems far beyond the reach of classical computers by using the principles of superposition and entanglement. However, existing platforms face challenges such as short coherence times, interference from the environment, and difficulties in scaling up.Trapped electrons in a planar Penning trap offer a promising alternative. Unlike other qubits, electrons do not interact with nuclear spins, which helps maintain quantum states for much longer. Additionally, their strong confinement allows for fast and precise quantum operations. In our approach, electron spins serve as logical qubits, while their motional states are used for entanglement. Our setup consists of 2-dimensional array of micro-sized Penning traps fabricated on a ceramic chip, placed inside a 1T superconducting magnet and cooled in a dilution refrigerator to reach millikelvin temperatures. This extreme cooling reduces unwanted motion and makes it possible to entangle electron spins and perform quantum gates with high accuracy. At Inter-University Accelerator Centre (IUAC), New Delhi, India, we are developing a prototype planar Penning trap. This new system offers a stable, scalable, and high-coherence platform for quantum computing.

Mauro Paternostro, Diogo de Oliveira Soares Pinto