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Abstract Neuromodulation technologies have gained considerable attention for their clinical potential in treating neurological disorders and advancing cognition research. However, traditional methods like electrical stimulation and optogenetics face technical and biological challenges that limit their therapeutic and research applications. A promising alternative, photoelectric neurostimulation, uses near‐infrared light to generate electrical pulses and thus enables stimulation of neuronal activity without genetic alterations. This study explores various design strategies to enhance photoelectric stimulation with minimally invasive, ultrasmall, untethered carbon electrodes. Employing a multiphoton laser as the near‐infrared (NIR) light source, benchtop experiments are conducted using a three‐electrode setup and chronopotentiometry to record photo‐stimulated voltage. In vivo evaluations utilize Thy1‐GCaMP6s mice with acutely implanted ultrasmall carbon electrodes. Results highlighted the beneficial effects of high duty‐cycle laser scanning and photovoltaic polymer interfaces on the photo‐stimulated voltages by the implanted electrode. Additionally, the promising potential of carbon‐based diamond electrodes are demonstrated for photoelectric stimulation and the application of photoelectric stimulation in precise chemical delivery by loading mesoporous silica nanoparticles (SNPs) co‐deposited with polyethylenedioxythiophene (PEDOT). Together, these findings on photoelectric stimulation utilizing ultrasmall carbon electrodes underscore its immense potential for advancing the next generation of neurostimulation technology.
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Development & characterization of electrodes for large-scale Xenon Time Projection Chambers
Abstract Dual-phase liquid xenon time projection chambers are the core detector elements of many experiments that conduct searches for Dark Matter and rare events, as well as in neutrino and high-energy physics. As part of this detector technology, high-voltage electrodes are instrumental for the generation of observable signals and their physical interpretation. Thus, electrode design and manufacturing has to fulfill stringent requirements, and their production is associated with significant engineering challenges. In this work we describe the successful development of electrodes on the 1.5 m-scale, from their design and simulation to subsequent assembly and high-voltage testing in a gaseous argon environment. The produced electrodes were recently installed as an anode and a cathode during an upgrade to the XENONnT experiment.
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- PAR ID:
- 10668747
- Publisher / Repository:
- IOP Publishing
- Date Published:
- Journal Name:
- Journal of Instrumentation
- Volume:
- 21
- Issue:
- 02
- ISSN:
- 1748-0221
- Page Range / eLocation ID:
- P02035
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1088/1748-0221/21/02/P02035
