Nedestruktivno slikanje in magnetometrija s Faradayevo rotacijo v plinu cezijevih atomov

magistrsko delo

Tina Arh (Author), Rok Žitko (Mentor), Peter Jeglič (Co-mentor)

Abstract

V magistrski nalogi je opisana uporaba Faradayevega pojava za izdelavo optičnega magnetometra z vročimi cezijevimi atomi, magnetometra s hladnimi cezijevimi atomi in za nedestruktivno slikanje hladnih atomov. Na začetku dela predstavimo fizikalno ozadje obravnavanih pojavov, predvsem paramagnetne Faradayeve rotacije, pa tudi Larmorjeve precesije in optičnega črpanja. V nadaljevanju opišemo osnovne principe delovanja optičnega magnetometra, pri čemer za boljše razumevanje prepletamo klasično in kvantnomehansko sliko pojavov, kot sta optično črpanje in Larmorjeva precesija. Predstavimo režime delovanja magnetometra in opišemo relaksacijske mehanizme, ki zavirajo idealno delovanje naprave. Nato opišemo izvedbo optičnega magnetometra v Laboratoriju za hladne atome, eksperimentalno postavitev in izbrane pogoje delovanja. Predstavimo eksperimente, ki nam omogočijo karakterizacijo optičnega črpanja, občutljivosti magnetometra in Faradayeve rotacije, ter pokažemo meritev radiofrekvenčnega šuma ozadja. V naslednjem poglavju se posvetimo eksperimentalni postavitvi magnetometra s hladnimi atomi, ki nam omogoča merjenje magnetnega polja v oblaku atomov pri temperaturi blizu absolutne ničle. Pojasnimo tudi manipulacijo atomskih stanj z radiofrekvenčnimi pulzi in izmerimo njene učinke. V zadnjem poglavju opišemo še osnovne principe nedestruktivnega Faradayevega slikanja hladnih atomov ter protokol zajemanja in obdelave slik. Pokažemo nekaj primerov opazovanja propagacije oblaka hladnih atomov s serijo Faradayevih slik in primerjavo destruktivnosti za različne frekvence žarka za slikanje. Nazadnje opišemo še načrte in ideje za nadaljnje delo in razvoj na vseh treh področjih.

Keywords

optični magnetometer;Faradayev pojav;Larmorjeva precesija;optično črpanje;Bell-Bloomov magnetometer;radiofrekvenčni magnetometer;cezijeva para;hladni atomi;radiofrekvenčni pulz;Rabijeva oscilacija;nedestruktivno slikanje;

Data

Language:	Slovenian
Year of publishing:	2019
Typology:	2.09 - Master's Thesis
Organization:	UL FMF - Faculty of Mathematics and Physics
Publisher:	[T. Arh]
UDC:	537
COBISS:	3370596
Views:	1430
Downloads:	269
Average score:	0 (0 votes)
Metadata:

Other data

Secondary language:	English
Secondary title:	Non-destructive imaging and magnetometry with Faraday rotation in a gas of cesium atoms
Secondary abstract:	In this thesis we describe the use of the Faraday effect for operation of an optical magnetometer with hot cesium vapor, a magnetometer with cold cesium atoms and for non-destructive imaging of cold atoms. In the beginning we present a theoretical background of the important phenomena, such as paramagnetic Faraday rotation, Larmor precession and optical pumping. Next, we describe the basic principles of operation of an optically pumped magnetometer, combining a quantum picture with the classical for better understanding. Three schemes of operation are presented, along with an explanation of the underlying principles that enable probing of the magnetometer response and some processes that suppress the perfect operation. Then we describe the realization of the optical magnetometer in the Cold Atom Laboratory, the chosen operation regime and the experimental setup. Some experiments for characterization of optical pumping, magnetometer sensitivity and Faraday rotation are shown, along with radio-frequency background noise measurements. In the next chapter we focus on experimental realization of the cold atom magnetometer that allows us to measure magnetic fields in an atomic cloud with temperatures close to absolute zero. Manipulation of the atomic states with radio-frequency pulses is explained and its effects are measured. In the last chapter we describe the basic principles of a non-destructive Faraday imaging of the cold atoms, the imaging protocol and analysis. We observe the propagation of the cold atom clouds with series of Faraday images and compare destructiveness for different detunings of the imaging beam. In the end, the plans and ideas for future work and development of the experiments in all three areas are described.
Secondary keywords:	optical magnetometer;Faraday effect;Larmor precession;optical pumping;Bell-Bloom magnetometer;radio-frequency magnetometer;cesium vapor;cold atoms;radio-frequency pulse;Rabi oscillation;non-destructive imaging;
Type (COBISS):	Master's thesis/paper
Study programme:	0
Thesis comment:	Univ. v Ljubljani, Fak. za matematiko in fiziko, Oddelek za fiziko
Pages:	66 str.
ID:	11242073