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Chemical Communications (Cambridge,... Feb 2023Due to its contactless and fuel-free operation, optical rotation of micro-/nano-objects provides tremendous opportunities for cellular biology, three-dimensional (3D)... (Review)
Review
Due to its contactless and fuel-free operation, optical rotation of micro-/nano-objects provides tremendous opportunities for cellular biology, three-dimensional (3D) imaging, and micro/nanorobotics. However, complex optics, extremely high operational power, and the applicability to limited objects restrict the broader use of optical rotation techniques. This Feature Article focuses on a rapidly emerging class of optical rotation techniques, termed optothermal rotation. Based on light-mediated thermal phenomena, optothermal rotation techniques overcome the bottlenecks of conventional optical rotation by enabling versatile rotary control of arbitrary objects with simpler optics using lower powers. We start with the fundamental thermal phenomena and concepts: thermophoresis, thermoelectricity, thermo-electrokinetics, thermo-osmosis, thermal convection, thermo-capillarity, and photophoresis. Then, we highlight various optothermal rotation techniques, categorizing them based on their rotation modes (, in-plane and out-of-plane rotation) and the thermal phenomena involved. Next, we explore the potential applications of these optothermal manipulation techniques in areas such as single-cell mechanics, 3D bio-imaging, and micro/nanomotors. We conclude the Feature Article with our insights on the operating guidelines, existing challenges, and future directions of optothermal rotation.
PubMed: 36723196
DOI: 10.1039/d2cc06955e -
Nature Communications Sep 2023Kagome metals AVSb (A = K, Cs, Rb) provide a rich platform for intertwined orders, where evidence for time-reversal symmetry breaking, likely due to the long-sought...
Kagome metals AVSb (A = K, Cs, Rb) provide a rich platform for intertwined orders, where evidence for time-reversal symmetry breaking, likely due to the long-sought loop currents, has emerged in STM and muon spin relaxation experiments. An isotropic component in the spontaneous optical rotation has also been reported and was interpreted as the magneto-optic Kerr effect. Intriguingly, the observed rotations differ by five orders of magnitude between different wavelengths and samples, suggesting more intricate physics. Here we report optical rotation and polar Kerr measurements in CsVSb crystals at the same wavelength. We observe large isotropic components of 1 milliradian in the optical rotation that do not respond to applied magnetic fields, while the spontaneous Kerr signal is less than 20 nanoradians. Our results prove unambiguously that the reported isotropic rotation is not from time-reversal symmetry breaking but represents the long-sought specular optical rotation and indicates a new intertwined order.
PubMed: 37658070
DOI: 10.1038/s41467-023-41080-5 -
Molecules (Basel, Switzerland) Dec 2022The controversial question of whether optical rotation data can be used to distinguish floral from honeydew honey was investigated. Specific optical rotation angles were...
The controversial question of whether optical rotation data can be used to distinguish floral from honeydew honey was investigated. Specific optical rotation angles were determined for 41 honey samples, including floral, honeydew, and adulterated honey, indicating that moderate to high positive optical rotation angles were found for all adulterated samples measured. A strong correlation between the sugar profile and the specific optical rotation angle of honey was confirmed, and a method based on C NMR metabolomics was proposed to calculate specific optical rotation angles with good correlation with the experimental values. The results indicate that optical rotation is not a reliable method for distinguishing the origin of honey but could indicate adulteration.
Topics: Honey; Optical Rotation; Magnetic Resonance Spectroscopy
PubMed: 36558078
DOI: 10.3390/molecules27248916 -
Science Advances Jun 2022Rotation of micro/nano-objects is important for micro/nanorobotics, three-dimensional imaging, and lab-on-a-chip systems. Optical rotation techniques are especially...
Rotation of micro/nano-objects is important for micro/nanorobotics, three-dimensional imaging, and lab-on-a-chip systems. Optical rotation techniques are especially attractive because of their fuel-free and remote operation. However, current techniques require laser beams with designed intensity profile and polarization or objects with sophisticated shapes or optical birefringence. These requirements make it challenging to use simple optical setups for light-driven rotation of many highly symmetric or isotropic objects, including biological cells. Here, we report a universal approach to the out-of-plane rotation of various objects, including spherically symmetric and isotropic particles, using an arbitrary low-power laser beam. Moreover, the laser beam is positioned away from the objects to reduce optical damage from direct illumination. The rotation mechanism based on opto-thermoelectrical coupling is elucidated by rigorous experiments combined with multiscale simulations. With its general applicability and excellent biocompatibility, our universal light-driven rotation platform is instrumental for various scientific research and engineering applications.
PubMed: 35704582
DOI: 10.1126/sciadv.abn8498 -
Nano Letters Sep 2020Optical rotation of laser tweezed nanoparticles offers a convenient means for optical to mechanical force transduction and sensing at the nanoscale. Plasmonic...
Optical rotation of laser tweezed nanoparticles offers a convenient means for optical to mechanical force transduction and sensing at the nanoscale. Plasmonic nanoparticles are the benchmark system for such studies, but their rapid rotation comes at the price of high photoinduced heating due to Ohmic losses. We show that Mie resonant silicon nanorods with characteristic dimensions of ∼220 × 120 nm can be optically trapped and rotated at frequencies up to 2 kHz in water using circularly polarized laser light. The temperature excess due to heating from the trapping laser was estimated by phonon Raman scattering and particle rotation analysis. We find that the silicon nanorods exhibit slightly improved thermal characteristics compared to Au nanorods with similar rotation performance and optical resonance anisotropy. Altogether, the results indicate that silicon nanoparticles have the potential to become the system of choice for a wide range of optomechanical applications at the nanoscale.
PubMed: 32787173
DOI: 10.1021/acs.nanolett.0c02240 -
Optics Express Sep 2020We design and fabricate a double-layered chiral metamaterial with 4-fold rotational symmetry, which simultaneously exhibits optical rotation and electromagnetically...
We design and fabricate a double-layered chiral metamaterial with 4-fold rotational symmetry, which simultaneously exhibits optical rotation and electromagnetically induced transparency (EIT) effects. Using analytical equivalent circuit model and Lorentz's coupled oscillator model, we interpret the physical mechanisms and derive material equations. Importantly, we find that magnetic dipole and electric quadrupole play important roles in optical rotation and keeping the symmetry of the material equations. Our work offers a better understanding of optical rotation in chiral metamaterials, and provides a new and simple approach to combine optical rotation and EIT effects into a single metamaterial.
PubMed: 33114849
DOI: 10.1364/OE.403421 -
Science Advances Nov 2022Light-induced rotation of microscopic objects is of general interest as the objects may serve as micromotors. Such rotation can be driven by the angular momentum of...
Light-induced rotation of microscopic objects is of general interest as the objects may serve as micromotors. Such rotation can be driven by the angular momentum of light or recoil forces arising from special light-matter interactions. However, in the absence of intensity gradient, simultaneously controlling the position and switching the rotation direction is challenging. Here, we report stable optical trapping and switchable optical rotation of nanoparticle (NP)-assembled micromotors with programmed phase of light. We imprint customized phase gradients into a circularly polarized flat-top (i.e., no intensity gradient) laser beam to trap and assemble metal NPs into reconfigurable clusters. Modulating the phase gradients allows direction-switchable and magnitude-tunable optical torque in the same cluster under fixed laser wavelength and handedness. This work provides a valuable method to achieve reversible optical torque in micro/nanomotors, and new insights for optical trapping and manipulation using the phase gradient of a spatially extended light field.
PubMed: 36399578
DOI: 10.1126/sciadv.add6664 -
The New Phytologist Jan 2020
Topics: Cell Wall; Color; Commelinaceae; Fruit; History, 20th Century; History, 21st Century; Nanostructures; Optical Rotation; Plant Physiological Phenomena; Research
PubMed: 31788822
DOI: 10.1111/nph.16263 -
Scientific Reports Feb 2019The process of unwinding and renaturation of DNA has been widely used in studies of nucleotide sequence organization. Compared with traditional methods for DNA unwinding...
The process of unwinding and renaturation of DNA has been widely used in studies of nucleotide sequence organization. Compared with traditional methods for DNA unwinding and renaturation, the label-free and non-destruction detection technology is significant and desiderated. We realized an optical system based on optical rotation via weak measurement for detection of single- and double-strand state of DNA. The optical rotation, which was induced by the status change of single and double DNA strands, was exploited to modulate the preselected polarization of a weak measurement system. With this modulation, the optical rotation caused by the separation of DNA strands can be determined through the center wavelength shift of the output spectrum. By monitoring the wavelength shift in real time, the separation processes of the DNAs with different base ratio (25% and 70%) and length (4nt and 40nt), and DNAs with three terminally modified cholesterol molecules were experimentally explored in varied pH and temperature conditions. In addition, the detection limit of the DNA concentration was obtained to be 5 × 10 mol/L. Our work based on optical rotation detection of single- and double-strand DNA exhibits the unique advantages of real-time monitoring, label-free, non-destruction and simplicity.
Topics: Base Sequence; DNA; DNA, Single-Stranded; Hydrogen-Ion Concentration; Nucleic Acid Renaturation; Quantum Theory; Temperature
PubMed: 30760805
DOI: 10.1038/s41598-018-38454-x -
ArXiv Jan 2023Controllable rotation of micro-/nano-objects provides tremendous opportunities for cellular biology, three-dimensional (3D) imaging, and micro/nanorobotics. Among...
Controllable rotation of micro-/nano-objects provides tremendous opportunities for cellular biology, three-dimensional (3D) imaging, and micro/nanorobotics. Among different rotation techniques, optical rotation is particularly attractive due to its contactless and fuel-free operation. However, optical rotation precision is typically impaired by the intrinsic optical heating of the target objects. Optothermal rotation, which harnesses light-modulated thermal effects, features simpler optics, lower operational power, and higher applicability to various objects. In this Feature Article, we discuss the recent progress of optothermal rotation with a focus on work from our research group. We categorize the various rotation techniques based on distinct physical mechanisms, including thermophoresis, thermoelectricity, thermo-electrokinetics, thermo-osmosis, thermal convection, and thermo-capillarity. Benefiting from the different rotation modes (i.e., in-plane and out-of-plane rotation), diverse applications in single-cell mechanics, 3D bio-imaging, and micro/nanomotors are demonstrated. We conclude the article with our perspectives on the operating guidelines, existing challenges, and future directions of optothermal rotation.
PubMed: 36713256
DOI: No ID Found