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VERSION:2.0
CALSCALE:GREGORIAN
PRODID:UW-Madison-Physics-Events
BEGIN:VEVENT
SEQUENCE:2
UID:UW-Physics-Event-5095
DTSTART:20190410T150000Z
DURATION:PT1H0M0S
DTSTAMP:20260313T113414Z
LAST-MODIFIED:20190410T142323Z
LOCATION:5280 Chamberlin Hall
SUMMARY:Few and many-body dynamics of Rydberg excitations in a lattice
 \, Atomic Physics Seminar\, Dr. David Petrosyan \, Institute of Electr
 onic Structure and Lasers\,   FORTH\, Heraklion\, Crete\, Greece
DESCRIPTION:Strong\, long-range\, resonant and dispersive dipole-dipol
 e interactions between the atoms in high-lying Rydberg states makes th
 em uniquely suited to simulate and study various spin-lattice models. 
 In this seminar\, I will discuss two proposals [1\,2] to implement spi
 n chains with interesting properties using Rydberg atoms in a lattice.
 <br>
\nI will show that an XXZ spin model with strong nearest-neighbor
  interactions and tunable long-range hopping of excitations can be rea
 lized by a regular array of laser driven atoms\, with an excited Rydbe
 rg state representing the spin-up state and a Rydberg-dressed ground s
 tate corresponding to the spin-down state [1]. This scheme permits the
  observation of coherent quantum dynamics of spin excitations - magnon
 s\, their scattering and exotic interaction-bound states.<br>
\nI will
  next describe a lattice of Rydberg superatoms - collections of atoms 
 in microtraps that can each accommodate at most one Rydberg excitation
 . The coupling of superatoms to the laser radiation is collectively en
 hanced and they can represent mesoscopic\, strongly polarizable spins.
  We studied a regular array of such effective spins driven by a laser 
 field tuned to compensate the interaction-induced level shifts between
  the neighboring superatoms [2]. After the initial transient with reso
 nantly facilitated excitation of large clusters of superatoms\, the sy
 stem relaxes to the steady state having nearly universal excitation de
 nsity of 2/3. This state is characterized by highly-nontrivial equilib
 rium dynamics of quasi-particles – excitation holes in the lattice o
 f Rydberg excited superatoms.<br>
\n<br>
\n[1] F. Letscher\, D. Petros
 yan\, Phys. Rev. A 97\, 043415 (2018)<br>
\n[2] F. Letscher\, D. Petro
 syan\, M. Fleischhauer\, New J. Phys. 19\, 113014 (2017)  
URL:https://www.physics.wisc.edu/events/?id=5095
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