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VERSION:2.0
PRODID:Icfo
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BEGIN:VEVENT
UID:6a0770944c95c
DTSTART:20240621T130000Z
SEQUENCE:0
TRANSP:OPAQUE
DTEND:20240621T140000Z
LOCATION:Seminar Room 
SUMMARY:ICFO | ZIXI LI
CLASS:PUBLIC
DESCRIPTION:A resonantly excited atomic optical dipole simultaneously gener
 ates a propagating (far-) and an evanescent (near-) electromagnetic field.
  The near-field component diverges in the limit of vanishing distance\, in
 dicating an optical antenna with potential for giant near-field intensity 
 enhancement. In principle\, any atomic optical dipole in a solid can serve
  as an optical antenna\; however\, most of them suffer from environment-in
 duced decoherence that largely mitigates field enhancement. Here\, we demo
 nstrate that germanium vacancy centers in diamond - optically-coherent ato
 m-like dipoles in a solid - are exemplary antennas. We measure up to milli
 on-fold optical intensity enhancement in the near-field of resonantly exci
 ted germanium vacancies. We utilize germanium vacancy antennas to detect a
 nd control the charge state of nearby carbon vacancies and generate measur
 able fluorescence from individual vacancies through Forster resonance ener
 gy transfer. Comparison with plasmonic nanospheres - a prototypical near-f
 ield enhancement medium -- shows that atomic antennas can generate orders-
 of-magnitude larger field intensity at nanometer lengthscales. Our study r
 eveals the capacity of atomic antennas for efficient optical energy concen
 tration in solids\, with broad applications in spectroscopy\, sensing\, an
 d quantum science.\n&nbsp\;
DTSTAMP:20260515T191428Z
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