arXiv subjects

Tali Dadosh

Publications and source records attributed to Tali Dadosh.

3 recordsLinked to original sources

arXiv2026

Continuous-Wave SOFISM with SPAD Array Detection

We present a continuous-wave (CW) implementation of super-resolution optical fluctuation imaging with image scanning microscopy (SOFISM) using a pixelated single-photon avalanche diode (SPAD) detector camera. In a scanning-based geometry, SOFISM requires fluorescence fluctuations on timescales compatible with the pixel dwell time while maintaining sufficient signal under confocal excitation. Photoswitchable fluorophores in an aqueous switching buffer containing the glucose oxidase-catalase oxygen-scavenging system (GLOXY) and mercaptoethylamine (MEA) were therefore used to promote blinking and reduce photobleaching. Correlation analysis of sparse-emitter measurements showed that Alexa Fluor 647 (AF647) exhibits microsecond-scale fluctuation dynamics suitable for CW SOFISM and guided the choice of imaging conditions for scanned samples. Frame rate and delay accumulation were optimized from detector-pair subset variability using a mean-to-STD criterion. The optimal binning time was 2.5 $\mu$s, underscoring the advantage of SPAD-based detection for resolving the relevant fluctuation dynamics. The method was demonstrated on HeLa cell microtubules labeled with AF647, yielding improved spatial resolution in the constructed SOFISM images compared with the corresponding ISM images. Additional super-resolved images from samples labeled with CF568 and Alexa Fluor 555 (AF555) showed the approach is readily generalizable to other fluorophores. These results establish CW SOFISM as a practical fluctuation-based super-resolution method for confocal microscopy.

physics.optics↗

arXiv2009

Controlling Nanogap Quantum Dot Photoconductivity through Optoelectronic Trap Manipulation

Nanoscale devices are being extensively studied for their tunable electronic and optical properties, but the influence of impurities and defects is amplified at these length scales and can lead to poorly understood variations in characteristics of semiconducting materials. By performing a large ensemble of photoconductivity measurements in nanogaps bridged by core-shell CdSe/ZnS semiconductor nanocrystals, we discover optoelectronic methods for affecting solid-state charge trap populations. We introduce a model that unifies previous work and transforms the problem of irreproducibility in nanocrystal electronic properties into a reproducible and robust photocurrent response due to trap state manipulation. Because traps dominate many physical processes, these findings may lead to improved performance and device tunability for various nanoscale applications through the control and optimization of impurities and defects.

cond-mat.mes-hall↗

arXiv2002

Fabrication of Nano-Scale Gaps in Integrated Circuits

Nano-size objects like metal clusters present an ideal system for the study of quantum phenomena and for constructing practical quantum devices. Integrating these small objects in a macroscopic circuit is, however, a difficult task. So far the nanoparticles have been contacted and addressed by highly sophisticated techniques which are not suitable for large scale integration in macroscopic circuits. We present an optical lithography method that allows for the fabrication of a network of electrodes which are separated by gaps of controlled nanometer size. The main idea is to control the gap size with subnanometer precision using a structure grown by molecular beam epitaxy.

cond-mat.mes-hall↗