Selective excitation of a particular fluorophore in the presence of others demands clever design of the optical field interacting with the molecules. We describe the use of 20- to 50-GHz pulse-train excitation leading to two-photon absorption, followed by successive one-photon stimulated emission as a potential technique in the context of controlling two-photon molecular fluorescence, with applications in microscopy.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1117/1.3509383 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
A compact Nd:YVO/Cr:YAG passively Q-switched laser in a near-hemispherical resonator is exploited to realize high-peak-power pulsed beams with high spatial degrees of freedom. Beneficial from the advantages of strong intracavity beam focusing as well as the point-like excitation condition for the proposed cavity design, various high-order structured pulses as coherent superpositions of multiple degenerate eigenmodes are stably generated under different off-axis pump schemes. Besides, by employing external-cavity astigmatic mode conversion (AMC), the oval-shaped and chessboard-like structured pulses under on-axis and 1D off-axis pumping are transformed into exotic modes with polygonal and figure-eight-shaped envelopes to further enrich the spatial complexity of the generated fields.
View Article and Find Full Text PDFMonitoring the Energy of a Cavity by Observing the Emission of a Repeatedly Excited Qubit.
Phys Rev Lett
October 2024
Ecole Normale Supérieure de Lyon, CNRS, Laboratoire de Physique, F-69342 Lyon, France.
The number of excitations in a large quantum system (harmonic oscillator or qudit) can be measured in a quantum nondemolition manner using a dispersively coupled qubit. It typically requires a series of qubit pulses that encode various binary questions about the photon number. Recently, a method based on the fluorescence measurement of a qubit driven by a train of identical pulses was introduced to track the photon number in a cavity, hence simplifying its monitoring and raising interesting questions about the measurement backaction of this scheme.
View Article and Find Full Text PDFMeasuring the total photon economy of molecular species through fluorescent optical cycling.
Phys Chem Chem Phys
August 2024
Department of Chemistry and Biochemistry, University of California, Los Angeles, 607 Charles E. Young Drive, Los Angeles, California 90095-1569, USA.
The total photon economy of a chromophore molecular species represents a study of how absorbed photons partition among various electronic states and ultimately dissipate their excited energy into the environment. A complete accounting of these rates and pathways would allow one to optimize chromophores and their environments for applications. We describe a technique, fluorescent optical cycling (FOC), which allows for simultaneous observation of prompt and delayed emission during and after multiple pulsed excitation, ultimately granting access to multi-state photophysical rates.
View Article and Find Full Text PDFTwo-photon imaging of excitatory and inhibitory neural response to infrared neural stimulation.
Neurophotonics
April 2024
Second Affiliated Hospital, Zhejiang University, Interdisciplinary Institute of Neuroscience and Technology, School of Medicine, Hangzhou, China.
Significance: Pulsed infrared neural stimulation (INS, 1875 nm) is an emerging neurostimulation technology that delivers focal pulsed heat to activate functionally specific mesoscale networks and holds promise for clinical application. However, little is known about its effect on excitatory and inhibitory cell types in cerebral cortex.
Aim: Estimates of summed population neuronal response time courses provide a potential basis for neural and hemodynamic signals described in other studies.
Optimizing assessment of low frequency H-reflex depression in persons with spinal cord injury.
PLoS One
May 2024
Crawford Research Institute, Shepherd Center, Atlanta, Georgia, United States of America.
Considering the growing interest in clinical applications of neuromodulation, assessing effects of various modulatory approaches is increasingly important. Monosynaptic spinal reflexes undergo depression following repeated activation, offering a means to quantify neuromodulatory influences. Following spinal cord injury (SCI), changes in reflex modulation are associated with spasticity and impaired motor control.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!