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View article: Room-temperature quantum entanglement in a van der Waals material
Room-temperature quantum entanglement in a van der Waals material Open
Entanglement is central to quantum science and technology. Atomic defects in two-dimensional (2D) van der Waals (vdW) materials offer exciting prospects for quantum sensing, with spatial resolution reaching 1 nm demonstrated using scanning…
View article: Coherent Spins in van der Waals Semiconductor GeS<sub>2</sub> at Ambient Conditions
Coherent Spins in van der Waals Semiconductor GeS<sub>2</sub> at Ambient Conditions Open
Optically active spin defects in van der Waals (vdW) materials have emerged as versatile quantum sensors, enabling applications for a wide range of quantum phenomena in condensed matter systems. Their ease of exfoliation and compatibility …
View article: Spin-State-Selective Excitation in Spin Defects of Hexagonal Boron Nitride
Spin-State-Selective Excitation in Spin Defects of Hexagonal Boron Nitride Open
Hexagonal boron nitride (hBN) has emerged as a promising two-dimensional platform for quantum sensing due to its optically addressable spin defects, such as the negatively charged boron vacancy (VB-). Spectral overlap of spin transitions d…
View article: Sub-Terahertz Spin Relaxation Dynamics of Boron-Vacancy Centers in Hexagonal Boron Nitride
Sub-Terahertz Spin Relaxation Dynamics of Boron-Vacancy Centers in Hexagonal Boron Nitride Open
Quantum sensors based on spin-defect relaxation have become powerful tools for detecting faint magnetic signals, yet their operation has remained largely confined to low magnetic fields and gigahertz frequencies. Extending such sensors int…
View article: Single nuclear spin detection and control in a van der Waals material
Single nuclear spin detection and control in a van der Waals material Open
Optically active spin defects in solids 1,2 are leading candidates for quantum sensing 3,4 and quantum networking 5,6 . Recently, single spin defects were discovered in hexagonal boron nitride (hBN) 7–11 , a layered van der Waals (vdW) mat…
View article: Nanotube spin defects for omnidirectional magnetic field sensing
Nanotube spin defects for omnidirectional magnetic field sensing Open
Optically addressable spin defects in three-dimensional (3D) crystals and two-dimensional (2D) van der Waals (vdW) materials are revolutionizing nanoscale quantum sensing. Spin defects in one-dimensional (1D) vdW nanotubes will provide uni…
View article: Single nuclear spin detection and control in a van der Waals material
Single nuclear spin detection and control in a van der Waals material Open
Optically active spin defects in solids are leading candidates for quantum sensing and quantum networking. Recently, single spin defects were discovered in hexagonal boron nitride (hBN), a layered van der Waals (vdW) material. Due to its t…
View article: Towards real-world applications of levitated optomechanics
Towards real-world applications of levitated optomechanics Open
Levitated optomechanics, a rapidly expanding field that employs light to monitor and manipulate the mechanical motion of levitated objects, is increasingly relevant across physics, engineering, and other fields. This technique, which invol…
View article: Giant enhancement of vacuum friction in spinning YIG nanospheres
Giant enhancement of vacuum friction in spinning YIG nanospheres Open
Experimental observations of vacuum radiation and vacuum frictional torque are challenging due to their vanishingly small effects in practical systems. For example, a nanosphere rotating at in free space slows down due to friction fro…
View article: Observation of non-contact Casimir friction
Observation of non-contact Casimir friction Open
Quantum mechanics predicts the occurrence of random electromagnetic field fluctuations, or virtual photons, in vacuum. The exchange of virtual photons between two bodies in relative motion could lead to non-contact quantum vacuum friction …
View article: Giant Enhancement of Vacuum Friction in Spinning YIG Nanospheres
Giant Enhancement of Vacuum Friction in Spinning YIG Nanospheres Open
Experimental observations of vacuum radiation and vacuum frictional torque are challenging due to their vanishingly small effects in practical systems. For example, a rotating nanosphere in free space slows down due to friction from vacuum…
View article: Isotope engineering for spin defects in van der Waals materials
Isotope engineering for spin defects in van der Waals materials Open
Spin defects in van der Waals materials offer a promising platform for advancing quantum technologies. Here, we propose and demonstrate a powerful technique based on isotope engineering of host materials to significantly enhance the cohere…
View article: Nanotube spin defects for omnidirectional magnetic field sensing
Nanotube spin defects for omnidirectional magnetic field sensing Open
Optically addressable spin defects in three-dimensional (3D) crystals and two-dimensional (2D) van der Waals (vdW) materials are revolutionizing nanoscale quantum sensing. Spin defects in one-dimensional (1D) vdW nanotubes will provide uni…
View article: Quantum control and Berry phase of electron spins in rotating levitated diamonds in high vacuum
Quantum control and Berry phase of electron spins in rotating levitated diamonds in high vacuum Open
Levitated diamond particles in high vacuum with internal spin qubits have been proposed for exploring macroscopic quantum mechanics, quantum gravity, and precision measurements. The coupling between spins and particle rotation can be utili…
View article: Optomechanics of optically-levitated particles: A tutorial and perspective
Optomechanics of optically-levitated particles: A tutorial and perspective Open
Optomechanics, the study of the mechanical interaction of light with matter, has proven to be a fruitful area of research that has yielded many notable achievements, including the direct detection of gravitational waves in kilometer-scale …
View article: Isotope engineering for spin defects in van der Waals materials
Isotope engineering for spin defects in van der Waals materials Open
Spin defects in van der Waals materials offer a promising platform for advancing quantum technologies. Here, we propose and demonstrate a powerful technique based on isotope engineering of host materials to significantly enhance the cohere…
View article: Coherent dynamics of strongly interacting electronic spin defects in hexagonal boron nitride
Coherent dynamics of strongly interacting electronic spin defects in hexagonal boron nitride Open
Optically active spin defects in van der Waals materials are promising platforms for modern quantum technologies. Here we investigate the coherent dynamics of strongly interacting ensembles of negatively charged boron-vacancy ( $${{{{{{{{\…
View article: Quantum sensing and imaging with spin defects in hexagonal boron nitride
Quantum sensing and imaging with spin defects in hexagonal boron nitride Open
Color centers in hexagonal boron nitride (hBN) have recently emerged as promising candidates for a new wave of quantum applications. Thanks to hBN’s high stability and two-dimensional (2D) layered structure, color centers in hBN can be rea…
View article: Quantum sensing of paramagnetic spins in liquids with spin qubits in hexagonal boron nitride
Quantum sensing of paramagnetic spins in liquids with spin qubits in hexagonal boron nitride Open
Paramagnetic ions and radicals play essential roles in biology and medicine, but detecting these species requires a highly sensitive and ambient-operable sensor. Optically addressable spin color centers in 3D semiconductors have been used …
View article: Quantum sensing and imaging with spin defects in hexagonal boron nitride
Quantum sensing and imaging with spin defects in hexagonal boron nitride Open
Color centers in hexagonal boron nitride (hBN) have recently emerged as promising candidates for a new wave of quantum applications. Thanks to hBN's high stability and 2-dimensional (2D) layered structure, color centers in hBN can serve as…
View article: Near-field GHz rotation and sensing with an optically levitated nanodumbbell
Near-field GHz rotation and sensing with an optically levitated nanodumbbell Open
A levitated non-spherical nanoparticle in a vacuum is ideal for studying quantum rotations and is an extremely sensitive torque and force detector. It has been proposed to probe fundamental particle-surface interactions such as the Casimir…
View article: Multiplane optical microscope
Multiplane optical microscope Open
This disclosure provides systems, methods, and apparatus related to optical microscopy. In one aspect, an apparatus includes a sample holder, a first objective lens, a plurality of optical components, a second objective lens, and a mirror.…
View article: Roadmap for optical tweezers
Roadmap for optical tweezers Open
Optical tweezers are tools made of light that enable contactless pushing, trapping, and manipulation of objects, ranging from atoms to space light sails. Since the pioneering work by Arthur Ashkin in the 1970s, optical tweezers have evolve…
View article: Coherent dynamics of strongly interacting electronic spin defects in hexagonal boron nitride
Coherent dynamics of strongly interacting electronic spin defects in hexagonal boron nitride Open
Optically active spin defects in van der Waals materials are promising platforms for modern quantum technologies. Here we investigate the coherent dynamics of strongly interacting ensembles of negatively charged boron-vacancy ($\mathrm{V}_…
View article: Observation and control of Casimir effects in a sphere-plate-sphere system
Observation and control of Casimir effects in a sphere-plate-sphere system Open
A remarkable prediction of quantum field theory is that there are quantum electromagnetic fluctuations (virtual photons) everywhere, which leads to the intriguing Casimir effect. While the Casimir force between two objects has been studied…
View article: Correlative Nanoscale Imaging of Strained hBN Spin Defects
Correlative Nanoscale Imaging of Strained hBN Spin Defects Open
Spin defects like the negatively charged boron vacancy color center ($V_B^-$) in hexagonal boron nitride (hBN) may enable new forms of quantum sensing with near-surface defects in layered van der Waals heterostructures. Here, we reveal the…
View article: Greatly Enhanced Emission from Spin Defects in Hexagonal Boron Nitride Enabled by a Low-Loss Plasmonic Nano-Cavity
Greatly Enhanced Emission from Spin Defects in Hexagonal Boron Nitride Enabled by a Low-Loss Plasmonic Nano-Cavity Open
Two-dimensional hexagonal boron nitride (hBN) has been known to host a variety of quantum emitters with properties suitable for a broad range of quantum photonic applications. Among them, the negatively charged boron vacancy (VB-) defect w…
View article: On-demand assembly of optically-levitated nanoparticle arrays in vacuum
On-demand assembly of optically-levitated nanoparticle arrays in vacuum Open
Realizing a large-scale fully controllable quantum system is a challenging task in current physical research and has broad applications. Ultracold atom and molecule arrays in optical tweezers in vacuum have been used for quantum simulation…