Peng Ju
Current Organizations / Institutes
The organizations/institutes from the scholar's latest article
Peng Ju has a total of 18 co-authors. Here are the top co-authors by number of shared publications:
Kunhong Shen
Department of Physics and Astronomy
3 shared publications- Tongcang Li
Department of Physics and Astronomy, Purdue University, West Lafayette, USA
3 shared publications - Sumukh Vaidya
Department of Physics and Astronomy
2 shared publications - Xingyu Gao
Department of Physics and Astronomy
2 shared publications Debasish Banerjee
Toyota Research Institute of North America
1 shared publication- Naveed Hussain
Toyota Research Institute of North America
1 shared publication
Latest Publications
- 30 March 2026
- Published by American Chemical Society (ACS) in Nano Letters
- Vol. 26 (13) , 4410-4417
Quantum Sensing of Opaque Materials with Plasmonically Enhanced Hexagonal Boron Nitride Spin Defects
Spin defects in hexagonal boron nitride (hBN) are emerging platforms for quantum sensing. The negatively charged boron vacancy () is widely studied due to its robust spin properties, but its low brightness often requires plasmonic enhancement, limiting sensing in optically opaque or scattering environments, such as batteries. Here, we design and nanofabricate a coplanar waveguide integrated with nanoslit arrays to enable back-side excitation and photoluminescence collection from hBN spin defects. Using a neon focused ion beam, we pattern periodic nanoslits through a thin gold film, allowing simultaneous microwave delivery and optical access through the substrate. We demonstrate device performance via T1 relaxometry and magnetic field mapping of nickel nanoparticles. This platform enables plasmonically enhanced quantum sensing in opaque materials and liquids, expanding applications beyond conventional transparent systems.- 30 March 2026
- Published by American Chemical Society (ACS) in Nano Letters
- Vol. 26 (13) , 4410-4417
Quantum Sensing of Opaque Materials with Plasmonically Enhanced Hexagonal Boron Nitride Spin Defects
Spin defects in hexagonal boron nitride (hBN) are emerging platforms for quantum sensing. The negatively charged boron vacancy () is widely studied due to its robust spin properties, but its low brightness often requires plasmonic enhancement, limiting sensing in optically opaque or scattering environments, such as batteries. Here, we design and nanofabricate a coplanar waveguide integrated with nanoslit arrays to enable back-side excitation and photoluminescence collection from hBN spin defects. Using a neon focused ion beam, we pattern periodic nanoslits through a thin gold film, allowing simultaneous microwave delivery and optical access through the substrate. We demonstrate device performance via T1 relaxometry and magnetic field mapping of nickel nanoparticles. This platform enables plasmonically enhanced quantum sensing in opaque materials and liquids, expanding applications beyond conventional transparent systems.- 1 November 2023
- Published by American Chemical Society (ACS) in Nano Letters
- Vol. 23 (22) , 10157-10163
Near-Field GHz Rotation and Sensing with an Optically Levitated Nanodumbbell
A levitated nonspherical nanoparticle in a vacuum is ideal for studying quantum rotations and is an ultrasensitive torque detector for probing fundamental particle-surface interactions. Here, we optically levitate a silica nanodumbbell in a vacuum at 430 nm away from a sapphire surface and drive it to rotate at GHz frequencies. The relative linear speed between the tip of the nanodumbbell and the surface reaches 1.4 km s-1 at a submicrometer separation. The rotating nanodumbbell near the surface demonstrates a torque sensitivity of (5.0 ± 1.1) × 10-26 N m Hz-1/2 at room temperature. Moreover, we probed the near-field laser intensity distribution beyond the optical diffraction limit with a nanodumbbell levitated near a nanograting. Our numerical simulations show that the system can measure the Casimir torque and will improve the detection limit of non-Newtonian gravity by several orders of magnitude.
- 1 November 2023
- Published by American Chemical Society (ACS) in Nano Letters
- Vol. 23 (22) , 10157-10163
Near-Field GHz Rotation and Sensing with an Optically Levitated Nanodumbbell
A levitated nonspherical nanoparticle in a vacuum is ideal for studying quantum rotations and is an ultrasensitive torque detector for probing fundamental particle-surface interactions. Here, we optically levitate a silica nanodumbbell in a vacuum at 430 nm away from a sapphire surface and drive it to rotate at GHz frequencies. The relative linear speed between the tip of the nanodumbbell and the surface reaches 1.4 km s-1 at a submicrometer separation. The rotating nanodumbbell near the surface demonstrates a torque sensitivity of (5.0 ± 1.1) × 10-26 N m Hz-1/2 at room temperature. Moreover, we probed the near-field laser intensity distribution beyond the optical diffraction limit with a nanodumbbell levitated near a nanograting. Our numerical simulations show that the system can measure the Casimir torque and will improve the detection limit of non-Newtonian gravity by several orders of magnitude.
- 12 July 2023
- Published by American Chemical Society (ACS) in ACS Photonics
- Vol. 10 (8) , 2894-2900
Quantum Sensing of Paramagnetic Spins in Liquids with Spin Qubits in Hexagonal Boron Nitride
- 12 July 2023
- Published by American Chemical Society (ACS) in ACS Photonics
- Vol. 10 (8) , 2894-2900
Quantum Sensing of Paramagnetic Spins in Liquids with Spin Qubits in Hexagonal Boron Nitride