PH6214/603: Physics of Ultracold Atoms (Ph. D/ MSc Elective)

Season 5 (2025) (Jan-May '25)

Lecture 1 (Introduction)

 





































Season 4 (2023) (October-November '23)

Lecture 1: Introduction (3rd October 23)

lecture 1 pptx (click to open)
 

Lecture 2: Origin of Radiation Pressure (4th October 23)

lecture 2 pptx (click to open)


Lecture 3: Concept of Doppler effect and Cooling (6th October 23)
 
lecture 3 pptx (click to open)


Lecture 4: Concept of Doppler effect and Cooling continued
 
lecture 4 pptx (click to open)


Lecture 5: Mathematiclal derivation of  Cooling Force

lecture 5 pptx (click to open)

Discussion on Semi-classical treatment  on derivation of excited state population using Time dependent Schrodinger wave equation For relevant material (Click here)


Lecture 6: Laser Cooling (contd)

lecture 6 pptx (click to open)


Lecture 7 : Laser Cooling (contd)

lecture 7 pptx (click to open)


Lecture 8 : Concept of Magneto Optical Trap (MOT)

lecture 8 pptx (click to open)


Lecture 9: Concept of Magneto Optical Trap (MOT)


lecture 9 pptx (click to open)



Lecture 10: Concept of Magneto Optical Trap (MOT)
Discussion on selection rules for different light polarization 

lecture 10 pptx (click to open)


Lecture 11: Force in  Magneto Optical Trap (MOT)

lecture 11 pptx (click to open)



Lecture 12: Experimental Sequence and Automation

lecture 12 pptx (click to open)



Lecture 13 and 14: Necessity of MOT and Multilevel treatment

lecture 13 and 14 pptx (click to open)

lecture 15: Forced Evaporative Cooling (click to open)


Practice Problem and Imaging of atoms

Season 3 (2023)
 

Lecture 1 (07/03/2023)

Introduction


 
 Lecture 2 (09/03/2023)

Concept of Laser cooling and Doppler effects in 1 -D

 Lecture 2 PPTX 
 
 Lecture 3 (13/03/2023)

Concept of Laser cooling and Doppler effects in 1 -D
contd

 Lecture 3 PPTX
 
 Lecture 4 (14/03/2023)

Finding an approximate mathematical expression for Laser cooling Force
in 1-D

 Lecture 4 PPTX

Discussion on Semi-classical treatment  on derivation of excited state population using Time dependent Schrodinger wave equation
For relevant material (Click here)
 
 
Lecture 5 (16/03/2023)

Concept of Laser cooling, Limitations of Laser cooling

Lecture 5 PPTX

 Lecture 6 (20/03/2023)
 
Vacuum assembly, Experimental sequence for Laser cooling

Lecture 6 PPTX 
 
 
Lecture 7 (21/03/2023) 

Experimental sequence for Laser cooling, Zeeman Effect
 
Lecture 7 PPTX  
 
 
Lecture 8 (23/03/2023) 

Concept of Magneto Optical Trap (MOT)

Lecture 8 PPTX  



Lecture 9 (27/03/2023) 

Concept of Magneto Optical Trap (MOT) continued

Lecture 9 PPTX  


Lecture 10 and 11

Concept of Magnetic Tapping

Lecture 10 and 11 PPTX



Lecture 12 and 13 (10/4/23 and 11/4/23)

Concept of Magnetic Trapping and evaporative cooling

Lecture 12 and 13 PPTX
 
 
 Lecture 14 (14/4/23)

Concept of RF induced  evaporative cooling (continued)
 
Lecture 14 PPTX  
 
 
 Lecture 15, 16 and 17

 Lecture 15, 16, 17  PPTX   
 
 
 
 Lecture 18 and 19

 Lecture 18,19  PPTX    
 



 
 
 

Lecture 1 (06/01/2020): 
 

Course Syllabus  and teaching plan for this course was discussed
Lecture_0 (Introduction) (Click to download PPT)


Lecture 2 (08/01/2020)

How Cold is Ultracold?, Quantum gas, atomic systems, Resonances, Atoms
and photons, Quantum Systems.

Lecture 3 (10/01/2020)

Doppler effect and laser, Doppler cooling of atomic gas using lasers
Click for ppt: Lec3 download

Lecture 4 (17/01/2020)

Concept of Doppler cooling revisited, Energy and Momentum Picture in detail,
Animations and Videos, Draw backs of Doppler cooling to reach Ultra low temperatures, Effect of Magnetic Field on atoms, Splitting of Hyper-fine lines and Zeeman effect.

Click for ppt: Lec4download

Lecture 5 (20/01/2020)

Limitations of Doppler Cooling, Effect of Light and Magnetic Field on atoms

Click for ppt: Lec5download

Lecture 6 (22/01/2020)

Concept of Zeeman Splitting, Spatial effects of light and polarization's on atoms,
Introduction to Magneto-Optical Trapping (MOT)

Click for ppt: Lec6download

Lecture 7 (24/01/2020)

MOT and  Doppler Cooling Sequence, Importance of MOT, Experiment Sequence

Last year Lectures/REFERENCES

Lecture 2 ( 08/01/2019):
 
Origin of cooling mechanisms and radiation pressure on atomic beams 

Supplementary review articles given in below links

1. https://cdn.journals.aps.org/files/RevModPhys.70.721.pdf

2. http://iopscience.iop.org/article/10.1088/1355-5111/7/1/002/pdf

3. https://getlink.pro/youtube/how-laser-cooling-works


Lecture 3 ( 09/01/2019):

Power point slide show on doppler cooling  (Click here to down load PPT)

Relevant videos on Optical molasses (Click to see videos)

1. Rb Laser cooling video
2. Optical Molasses

Laser cooling leads to a velocity dependent force and it is limited to Doppler limited temperature. Spatial 
confinement could be added using Zeeman splitting this is called as Magneto Optical Trapping (MOT).

Introduction to MOT is given in this lecture

Lecture 4 ( 11/01/2019):

Power point slide show on MOT  (Click here to down load PPT)

Concept of Magneto Optical Trapping (MOT) using two level model will be explained in this lecture

Lecture 5 ( 15/01/2019)

Spatial confinement of atoms achieved with the Zeeman Splitting 
Polarization of light play a major role in space selective laser cooling
Sigma+ Sigma- configuration is discussed 
MOT configuration is discussed

Lecture 6 (17/01/2019)

Difference between Optical Molasses and MOT discussed

Laser frequency de-tunings for MOT 

Vacuum Chamber of MOT and Rb atoms inside the Science Chamber

Experimental Sequence of MOT

Lecture 7 (18/01/2019)

Mathematical formulation of Laser cooling Force

Momentum equation and derivation of scattering Force

Discussion on Semi-classical treatment  on derivation of excited state population 
using Time dependent Schrodinger wave equation

For relevant material (Click here)

Lecture 8 (22/01/2019)

Scattering Force in the presence of Co-propagating and Counter Propagating beams

Mathematical derivation of Net cooling Force (Optical Molasses)

Force takes the form of a velocity dependent damped force


Lecture 9 (24/01/2019)

Forces in Magneto-optical trap

Detuning and Scattering Force for sigma +  and sigma minus polarized light

Mathematical representation

Lecture 10 (25/01/2019)

Mathematical derivation of net cooling Forces in Magneto-optical trap (Continued)

Lecture 11 (29/01/2019)

Mathematical derivation of net cooling Forces in Magneto-optical trap

Net force takes the form of a Damped Harmonic Oscillator

Heating and Cooling rates in MOT

Derivation of Doppler limit Temperature achieved in MOT
Limitations of MOT
Relevant Materials
1. Derivation of Optical Molasses Cooling Force
2. Derivation of Net Force in a MOT
3. Laser cooling and Trapping (W.D. Philips and H.J. Metcalf)

Lecture 12 (07/02/2019)

Tutorial I - Discussion (Click to open)


Lecture 13 (08/02/2019)

Tutorial I - Discussion  Continued (Click to open)


Lecture 14  (12/02/2019)

Laser cooling of Multi-level atoms (Rubidium as an example)

Role of Repumping Laser light in Multi-level atoms

Lecture 15  (14/02/2019)

Magneto-Optical Trapping  of Multi-level atoms (Rubidium as an example)

Lecture 16  (15/02/2019)

Concept and Principle behing Magnetic trapping

A conservative potential for laser cooled atoms

Lecture 17  (19/02/2019)

Quiz I

MID SEMESTER EXAM 26/2/2019

Lecture 18  (05/03/2019)

Magnetic Trap Loading and Concept of Evaporative Cooling

Radio frequency based Evaporative cooling