Koherentni efekti u hladnom atomskom plinu

master's thesis

• Title (english): Coherent effects in cold atomic gas
• Author: Mateo Kruljac
• Mentor: Damir Aumiler (mentor)
• Mentor: Damir Veža (mentor)
• Committee member: Damir Veža (predsjednik povjerenstva)
• Committee member: Damir Aumiler (član povjerenstva)
• Committee member: Ivica Smolić (član povjerenstva)
• Committee member: Davor Horvatić (član povjerenstva)
• Committee member: Hrvoje Buljan (član povjerenstva)
• Granter: University of Zagreb; Faculty of Science; (Department of Physics); Zagreb
• Defense date and country: 2018-07-04, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Physics

Abstract

U ovome radu proučavani su koherentni efekti u hladnom atomskom plinu izotopa rubidija 87Rb uslijed interakcije s dva lasera. Predstavljena je teorijska pozadina interakcije dvaju lasera s atomom u lambda konfiguraciji, pri čemu je jedan laser kontinuiranog zračenja, a drugi femtosekundni (pulsni) laser. Odabrani su prijelazi rubidija 52S1/2(F = 1) → 52P3/2(F’ = 2) i 52S1/2(F = 2) → 52P3/2(F’ = 2). Predstavljena je i pozadina laserskog hlađenja i zarobljavanja atoma radi stvaranja hladnog atomskog oblaka, a objašnjene su specifičnosti femtosekundnog lasera koje omogućuju ispitivanje koherentnih efekata. Predstavljene su metode frekventne stabilizacije lasera kontinuiranog zračenja i femtosekundnog lasera, potrebne za visoku preciznost mjerenja. Rezultati su dobiveni mjerenjem sile laserskog zračenja na hladni oblak rubidija, kao i mjerenjem laserski inducirane fluorescencije oblaka uslijed interakcije s laserima. Mjerenja su uspoređena s teorijom, a u skladu su s numeričkim modelom, što potvrđuje mogućnost korištenja femtosekundnog lasera za ispitivanje koherentnih efekata.

Abstract (english)

In this thesis we studied coherent effects in a cold atomic gas of rubidium isotope 87Rb interacting with two lasers. A theoretical background on the interaction of two lasers with an atom in lambda configuration is presented. One of the lasers is a continuous-wave laser, while the other is a pulsed, femtosecond laser. Rubidium transitions 52S1/2(F = 1) → 52P3/2(F’ = 2) and 52S1/2(F = 2) → 52P3/2(F’ = 2) were chosen and used, as they correspond to a lambda configuration. Also presented is a short theory of laser cooling and trapping, which is used to make a cloud of cold rubidium atoms for the experiment of coherent effects. We explain the methods of frequency stabilization of continuous-wave and femtosecond lasers, needed for measurements of high precision. The results were acquired by measuring laser radiation force on a rubidium cloud, as well as by measuring laser induced fluorescence of the cloud interacting with the lasers. We compared the measurements to the theoretical predictions and they correspond very well to the numerical models. We conclude that the femtosecond laser is a very useful tool which can be used in the experiments focused on coherent effects, as well as continuous-wave lasers have been used.

• Keywords: femtosekundni laser; koherencija; lambda konfiguracija; atom rubidija; sila zračenja
• Keywords (english): femtosecond laser; coherence; lambda configuration; rubidium atoms; radiation force
• Language: croatian
• URN:NBN: urn:nbn:hr:217:949848
• Study programme: Title: Physics; specializations in: Research; Course: Research; Study programme type: university; Study level: integrated undergraduate and graduate; Academic / professional title: magistar/magistra fizike (magistar/magistra fizike)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2018-07-13 13:25:43