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Quadrupolar Resonance Spectroscopy of Individual Nuclei Using a Room-Temperature Quantum Sensor
S Alex Breitweiser1,2, Mathieu Ouellet1, Tzu-Yung Huang1
1Quantum Engineering Laboratory, Department of Electrical and Systems Engineering, University of Pennsylvania, 200 S. 33rd St., Philadelphia, Pennsylvania 19104, United States.
Nano Letters
|December 12, 2024
Summary
Researchers used nitrogen-vacancy centers in diamond to perform nuclear quadrupolar resonance (NQR) spectroscopy on individual nitrogen-14 nuclei. This technique revealed subtle variations between nuclei and uncovered a new quadrupolar term.
Area of Science:
- Quantum Information Science
- Solid-State Physics
- Spectroscopy
Background:
- Nuclear quadrupolar resonance (NQR) spectroscopy probes chemical bonding via nuclear spin interactions.
- Traditional NQR requires large ensembles, masking individual molecular variations.
- Solid-state spin qubits, like nitrogen-vacancy (NV) centers in diamond, enable single nuclear spin control and readout.
Purpose of the Study:
- To utilize NV centers for high-resolution NQR spectroscopy at the single-nucleus level.
- To investigate molecule-to-molecule variations in nuclear quadrupolar interactions.
- To explore quantum control of nuclear spins using NQR.
Main Methods:
- Performed NQR spectroscopy on nitrogen-14 (14N) nuclei associated with NV centers in diamond at room temperature.
- Mapped the nuclear quadrupolar Hamiltonian for individual nuclei.
- Designed quantum pulse sequences for initializing, reading out, and controlling the 14N nuclear spin state.
Main Results:
- Resolved minute, individual variations in the nuclear quadrupolar Hamiltonian.
- Identified correlations between NV electronic and 14N nuclear spin states.
- Discovered a previously unreported symmetry-breaking quadrupolar term.
Conclusions:
- NV-center-based NQR spectroscopy offers unprecedented resolution for studying nuclear spin interactions.
- This technique reveals subtle variations and new physics in solid-state systems.
- Quantum control of nuclear spins via NQR opens avenues for quantum sensing and information processing.
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