Acoustic tweezers

Abstract

Acoustic tweezers are gaining increasing attention as a noncontact method that is capable of handling microparticles and nanoparticles in a controllable manner. By designing the acoustic field, objects, such as cells, bacteria, exosomes, and even worms, could be precisely and flexibly manipulated by the acoustic radiation force. With the advantages of non-invasiveness, label-free operation, and low power consumption, acoustic tweezers have been proven to be crucially important for a diverse range of applications, particularly in the biomedical domain. In this paper, we review the historical development and the current state of the theory of the acoustic radiation force. Furthermore, we introduce recent advancements in acoustic tweezers based on the standing wave, travelling wave, single beam, and arbitrary wave fields; its mechanism and potential applications are also presented. Finally, some perspectives referring to the future development of acoustic tweezers are discussed.

Interstate vibronic coupling constants between electronic excited states for complex molecules

“…The elements of the coupling matrix ( ) represent the changes in the excited state potentials with respect to 0 ( ) and vary smoothly as a function of nuclear displacements. They are expanded in Taylor series around the reference geometry (here taken to be the Franck-Condon point, Q=0): 19 , butatriene cation 20 , benzene cation 21 and its fluoroderivatives, 22,23,24 naphthalene and anthracene cations, 25 …), and also transition metal complexes. 26,27,28,29 In molecules with symmetry, selection rules strongly restrict the number of non-zero electronic-vibrational coupling constants which largely simplifies the problem of parametrizing these constants.…”

Nanomaterial Patterning in 3D Printing

“…On the other hand, SAWs oscillate in the range of tens to hundreds of megahertz, localized to the surface of the element. They are often generated by patterned interdigitated transducers (IDT), which expand and contract a piezoelectric material 287,292. This continuous deformation generates SAWs that propagate along the longitudinal and transverse directions.…”

“…This continuous deformation generates SAWs that propagate along the longitudinal and transverse directions. Waves vibrating at higher frequency have a shorter wavelength rendering them suitable for attaining superior spatial resolution 292. For instance, the frequency of SAWs vibrating at 100 MHz corresponds to a wavelength of less than 100 µm, making them desirable for higher resolution patterning.…”

The effect of site-specific spectral densities on the high-dimensional exciton-vibrational dynamics in the FMO complex

“…The particular choice of this tree strongly influences the required numerical effort [31,34]; for applications to coupled electron-vibrational dynamics, see also Refs. [35,36]. In the following simulations we use a grouping according to the magnitude of the HR factor and frequency as detailed in Ref.…”