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Initializing 214 Pure 14-Qubit Entangled Nuclear Spin States in a Hyperpolarized Molecular Solid
Gerd Kothe1, Michail Lukaschek1, Tomoaki Yago2
1Department of Physical Chemistry, University of Freiburg, Albertstrasse 21, 79104 Freiburg, Germany.
The Journal of Physical Chemistry Letters
|April 7, 2021
Summary
Molecular solids enable high-dimensional quantum entanglement. Researchers achieved entanglement of 14 nuclear spins, creating over 10,000 multiqubit entangled states for quantum computing.
Area of Science:
- Quantum physics
- Materials science
- Quantum information science
Background:
- Quantum entanglement is key for quantum computing.
- Existing platforms like quantum dots and superconductors have limitations.
- Molecular solids offer a promising alternative for realizing quantum entanglement.
Purpose of the Study:
- To introduce molecular solids as a novel platform for quantum entanglement.
- To demonstrate high-dimensional multiqubit entanglement in a molecular system.
- To explore the potential of molecular solids for large-scale quantum information processing.
Main Methods:
- Utilized triplet pentacene in a host single crystal under level anticrossing conditions.
- Employed laser pulses to generate triplet states and initiate electron spin-nuclear spin entanglement.
- Used microwave pulses to disentangle electron spin and create multiqubit entanglement among proton spins.
Main Results:
- Successfully generated entanglement between an electron spin and 14 proton spins (qubits).
- Achieved high nuclear spin polarization.
- Verified the initialization of 2^14 pure 14-qubit entangled nuclear spin states.
- Obtained an average degree of entanglement (E_av) of 0.77 ± 0.03.
Conclusions:
- Demonstrated the feasibility of using molecular solids for quantum entanglement.
- Showcased the creation of high-dimensional multiqubit entanglement.
- Opened pathways for quantum information processing with over 10,000 multiqubit entangled states and computational space dimensions exceeding 10^53.
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