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<p style="text-align:center;margin:0px" align="center"><b><span
style="font-family:'century gothic' ,
sans-serif;color:#5f5f5f" lang="EN-GB">Institut za fiziku,
Bijenička cesta 46,</span></b></p>
<p style="text-align:center;margin:0px" align="center"><b><span
style="font-family:'century gothic' ,
sans-serif;color:#5f5f5f" lang="EN-GB">predavaonica u
zgradi Mladen Paić</span></b></p>
<strong><b><span style="font-size:14pt;font-family:'century
gothic' , sans-serif;color:#993300" lang="EN-GB">srijeda,
25. 09. 2019. u 15:00 sati</span></b><br>
</strong></div>
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roman", "new york", times, serif; font-size:
12pt; text-align: center;"><strong></strong> </div>
<div style="text-align: center;"><span style="color: rgb(85, 145,
60); font-family: "times new roman", serif;
font-size: 12pt;"><span style="font-size:21.3333px"><b><font
face="times new roman, serif">Light beams carrying
orbital angular momentum interacting with cold atoms</font></b></span></span><font
face="times new roman, serif" color="#55913c"><span
style="font-size: 21.3333px;"></span></font></div>
<div style="text-align: center;"><font face="century gothic,
sans-serif"><span style="font-size: 18.6667px;"><b>dr. Hamid
Reza Hamedi</b></span></font></div>
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roman", "new york", times, serif; font-size:
12pt; text-align: center;"> </div>
<div style="text-align: center;">
<div style="text-align: center;"><font face="century gothic,
sans-serif"><span style="font-size: 14.6667px;"><b>Institute
of Theoretical Physics and Astronomy, Vilnius
University, Sauletekio 3, Vilnius LT-10257, Lithuania</b></span></font><span
style="font-size:small;font-family:'arial'"></span> </div>
</div>
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roman", "new york", times, serif; font-size:
12pt; text-align: center;"><span
style="font-size:small;font-family:'arial'"></span> </div>
The interaction of coherent light with atomic systems allow
observation of several important and interesting quantum
interference effects such as coherent population trapping (CPT),
electromagnetically induced transparency (EIT) and stimulated
Raman adiabatic passage (STIRAP). These phenomena are based on the
coherent preparation of atoms in a so-called dark state which is
immune against the loss of population through the spontaneous
emission. On the other hand, light can carry an orbital angular
momentum (OAM). Such light beams have helical (twisted) wavefronts
that spiral along the beam direction much like a corkscrew. A
number of interesting effects appear when this type of optical
beams interact with the atomic systems. Among them optical
vorticities of slow light have caused a considerable interest, as
the OAM brings a new degree of freedom in manipulation of the
optical information during the storage and retrieval of the slow
light [1]. We have devoted some attention to the interplay of
light carrying OAM and atomic systems. During this talk, I will
review some of our recent works on different scenarios for the
exchange of optical vortices in atom-light coupling setups [2-4].
I will try to talk also about a scenario for detection of the
structured light by measuring the absorption profile of a weak
nonvortex probe beam in a highly resonant five-level atom-light
coupling setup [5]. <br>
<br>
[1] R. Pugatch, M. Shuker, O. Firstenberg, A. Ron, and N.
Davidson, Phys. Rev. Lett. 98, 203601 (2007).<br>
[2] H. R. Hamedi, J. Ruseckas, and G. Juzeliūnas, Phys. Rev. A 98,
013840 (2018).<br>
[3] H. R. Hamedi, J. Ruseckas, E. Paspalakis, and G. Juzeliūnas,
Phys. Rev. A 99, 033812 (2019).<br>
[4] H. R. Hamedi, E. Paspalakis, G. Žlabys, G. Juzeliūnas, and J.
Ruseckas, Phys. Rev. A 100, 023811 (2019)<br>
[5] H. R. Hamedi, V. Kudriašov, J. Ruseckas, and G. Juzeliūnas,
Opt. Express 26, 28249-28262 (2018).<br>
<br>
</div>
<div style="color: rgb(0, 0, 0); font-family: arial, helvetica,
sans-serif; font-size: 12pt; text-align: left;"><b><span
style="font-size:12pt;font-family:'century gothic' ,
sans-serif" lang="EN-GB"><b><span
style="font-size:11pt;font-family:'century gothic' ,
sans-serif" lang="EN-GB"> </span></b></span></b><b><span
style="font-size:12pt;font-family:'century gothic' ,
sans-serif" lang="EN-GB"><b><span
style="font-size:11pt;font-family:'century gothic' ,
sans-serif" lang="EN-GB">Voditelji seminara IF-a: <a
href="mailto:balog@ifs.hr">Ivan Balog</a> i <a
href="mailto:ddominko@ifs.hr">Damir Dominko</a></span></b></span></b></div>
<pre class="moz-signature" cols="72">--
Damir Dominko
Research associate
Institute of Physics Zagreb
Bijenicka cesta 46, 02-226
10000 Zagreb, Croatia
office: +385 1 469 8821
cell: +385958172990
e-mail: <a class="moz-txt-link-abbreviated" href="mailto:ddominko@ifs.hr">ddominko@ifs.hr</a></pre>
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