CNTQUBIT · Carbon nanotube based nanomechanical qubit
Horizon 2020 — Marie Skłodowska-Curie Actions
- Duration
- 2021-04-01 → 2023-03-31
- EU contribution
- €160,932
- Participants
- 1
- Scheme
- MSCA-IF
Lines connect the coordinator with its partners.
Results in brief
Carbon nanotube based nanomechanical qubit
Many modern challenges such as climate change and food security are difficult to address using classical computing. Quantum computers are expected to fare much better, because their fundamental computing unit, the quantum bit (qubit) can utilize quantum properties such as entanglement. These qubits are in practice realized on a specific hardware platform, but so far, no particular architecture has demonstrated superiority. This project sought to demonstrate a fundamentally new type of platform to host such qubits. The qubit is realized with a carbon nanotube (CNT) whose mechanical vibrations are coupled to an embedded and trapped electron. The first objective was to demonstrate the interplay between the vibrations and the electron, whilst the second was to utilize this coupling for the formation of a qubit. The image shows a scanning electron micrograph image of our platform. The carbon nanotube is indicated by the red arrows are grows from catalyst nanoparticles in the blue regions. The electron is confined along the suspended nanotube in the small region indicated by the dashed yellow rectangle by applying voltages to the electrodes highlighted in red.
Data: CORDIS, © European Union
Project objective
This proposal outlines our vision for generating the first mechanical quantum bit (qubit) ever produced. The qubit will be realized with a carbon nanotube (CNT) in two steps. First, a carbon nanotube mechanical resonator is prepared in its quantum ground state and strongly coupled to an embedded electronic two-level system (eTLS). The eTLS is realized by carefully tuning the energy states of two spatially distinct charge quantum dots until they hybridize. This double quantum dot is hosted along the suspended carbon nanotube and localized such that it couples strongly to a high mechanical quality factor vibrational mode. Secondly, the strong coupling between the emergent eTLS and the CNT mechanical mode enables a tunable and strong anharmonicity in the mechanical restoring potential. This anharmonicity makes it possible to use the system as a qubit, which will be realized by integrating the nano-electromechanical (NEMS) device with a superconducting microwave cavity. This allows for the mechanical qubit to be coherently addressed and sensitively read-out using the state-dependent frequency shift imparted by the qubit on the superconducting cavity.
Original text from CORDIS.
Participants
- FUNDACIO INSTITUT DE CIENCIES FOTONIQUES · CastelldefelsCoordinatorSpain
Links
Data: CORDIS, © European Union