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DTSTAMP:20260404T110135Z
UID:624ea2960cf4f929701808@ist.ac.at
DTSTART:20220504T110000
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DESCRIPTION:Speaker: Helmut Ritsch\nhosted by Johannes Fink\nAbstract: An a
 rray of closely spaced\, dipole coupled quantum emitters exhibits collecti
 ve energy shifts as well as super- and sub-radiance with characteristic ta
 ilorable spatial radiation patterns. In particular optical absorption and 
 emission properties of ring shaped sub-wavelength nanoscopic quantum emitt
 er structures are unique. As striking example we identify a sub-wavelength
  sized ring of exactly 9 identical dipoles with an extra identical emitter
  with a extra loss channel at the center as the most efficient configurati
 on to deposit incoming photon energy to center without reemission.The enha
 ncement is most pronounced a given resonance frequency but still stays vis
 ible for broadband light absorption. For very tiny structures below a tent
 h of a wavelength a full quantum description exhibits an even larger enhan
 cement than predicted from a classical dipole approximation.The origin of 
 the effect can be tied to a specific geometric property of nonagons allowi
 ng for the appearance of a special collective dark state with dominant cen
 ter occupation. By special design of the center absorber one can harness t
 he same efficiency enhancement also at different wavelengths and for other
  geometric structures.On the one hand this could be the basis of a new gen
 eration of highly efficient and selective nano antennas for single photon 
 detectors for microwaves\, infrared and optical frequencies as used e.g. i
 n quantum information processing or single molecule spectroscopy\, while o
 n the other hand it could be an important piece towards understanding the 
 surprising efficiency of natural light harvesting molecules.Adding gain to
  such systems allows to design minimalistic classical as well as non-class
 ical light sources.References:Holzinger\, Raphael\, Mariona Moreno-Cardone
 r\, and Helmut Ritsch. "Nanoscale continuous quantum light sources based o
 n driven dipole emitter arrays\, Appl. Phys. Lett. 2021Holzinger\, Raphael
 \, et al. "Nanoscale coherent light source." Physical Review Letters 124.2
 5 (2020): 253603Moreno-Cardoner\, Maria\, Raphael Holzinger\, and Helmut R
 itsch. "Efficient frequency-selective single-photon antennas based on a bi
 o-inspired nano-scale atomic ring design with 9-fold symmetry." arXiv prep
 rint arXiv:2010.09771 (2020).
LOCATION:Heinzel Seminar Room / Office Bldg West (hybrid enabled) (I21.EG.1
 01)\, ISTA
ORGANIZER:swiddman@ist.ac.at
SUMMARY:Helmut Ritsch: Minimalistic efficient quantum devices build of dipo
 le coupled nano arrays of quantum emitters
URL:https://talks-calendar.ista.ac.at/events/3706
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