D. Moraru | Searcharxiv

arXiv2024

Ultra-sensitive Short-Wave Infrared Single-Photon Detection using a Silicon Single-Electron Transistor

Ultra-sensitive short-wave infrared (SWIR) photon detection is a crucial aspect of ongoing research in quantum technology. However, developing such detectors on a CMOS-compatible silicon technological platform has been challenging due to the low absorption coefficient for silicon in the SWIR range. In this study, a codoped silicon-based single-electron transistor (SET) in a silicon-on-insulator field-effect transistor (SOI-FET) configuration is fabricated, which successfully detects single photons in the SWIR range with ultra-high sensitivity. The detection mechanism is evidenced by the shift in the onset of the SET current peaks and by the occurrence of random telegraph signals (RTS) under light irradiation, as compared to the dark condition. The calculated sensitivity of our device, in terms of noise equivalent power, is approximately 10-19 W Hz-1/2.

physics.app-ph↗

arXiv1998

Power Law Decays in the Optical Counterparts of GRB 970228 and GRB970508

We report on R_c and K band observations of the optical counterpart to GRB 970508 with the Fred Lawrence Whipple Observatory (FLWO) 1.2m telescope. Eleven R_c-band observations were obtained on 1997 May 12, and three on May14. The counterpart clearly faded between the two nights. On May 12 there was no evidence for variability (<9%) on 10-70 minute time scales based on 11 R_c-band observations. On May 19 a one hour observation set a limit on the K magnitude of K>18.2. Comparison of these data points with those obtained by other authors shows that the decay of the optical counterpart can be well fitted by a power law of the form f ~ t**-alpha where alpha = 1.22 +/- 0.03 with occasional fluctuations superposed. We note that the decay of the optical counterpart to another burst, GRB 970228, can also be well fitted with a power law with exponent alpha = 1.0/+0.2/-0.5 with occasional fluctuations superposed. These two decay light curves are remarkably similar in form to that predicted by cosmic-fireball models.

astro-ph↗