1. Purdue University Spring 2014 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 6 (2/5/2014) Slide 1yongchen@purdue.edu Introduction to Quantum Optics & Quantum Photonics PHYS522 ECE695 (“Coherent Optics & Quantum Electronics”) http://www.physics.purdue.edu/academic_programs/courses/phys522/ Lecture 7 Light-Matter Interaction 1: Radiative Transitions (Atoms & Molecules) Reminder: HWK2 due Lecture notes taker

2. Purdue University Spring 2014 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 6 (2/5/2014) Slide 2yongchen@purdue.edu Introduction to Quantum Optics & Quantum Photonics PHYS522 ECE695 (“Coherent Optics & Quantum Electronics”) http://www.physics.purdue.edu/academic_programs/courses/phys522/ Course Outline Part 1: basic review: Optics+Quantum; Part 2: Basic Light- matter interaction; laser; Part 3: Quantum Optics of photons Part 4: More advanced light-matter interaction Part 5: Quantum information/photonics/ applications Subject to change; Check updates on course web/wiki

3. Purdue University Spring 2014 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 6 (2/5/2014) Slide 3yongchen@purdue.edu Introduction to Quantum Optics & Quantum Photonics PHYS522 ECE695 (“Coherent Optics & Quantum Electronics”) http://www.physics.purdue.edu/academic_programs/courses/phys522/ This Lecture Radiative transition in atom (2-level) (FQ Chap 4.1-4.4; also helpful: FS Appendix B) Transitions on Molecules (FS Chap 8.2)

4. Purdue University Spring 2014 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 6 (2/5/2014) Slide 4yongchen@purdue.edu Introduction to Quantum Optics & Quantum Photonics PHYS522 ECE695 (“Coherent Optics & Quantum Electronics”) http://www.physics.purdue.edu/academic_programs/courses/phys522/ Classical & Semiclassical L-M interaction 00 Classical Semi-Classical (Lorentz)dipole oscillator model

5. Purdue University Spring 2014 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 6 (2/5/2014) Slide 5yongchen@purdue.edu Introduction to Quantum Optics & Quantum Photonics PHYS522 ECE695 (“Coherent Optics & Quantum Electronics”) http://www.physics.purdue.edu/academic_programs/courses/phys522/ “Driven damped Harmonic Oscillator” Powerful mechanical analogue of L-M interaction γ

6. Purdue University Spring 2014 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 6 (2/5/2014) Slide 6yongchen@purdue.edu Introduction to Quantum Optics & Quantum Photonics PHYS522 ECE695 (“Coherent Optics & Quantum Electronics”) http://www.physics.purdue.edu/academic_programs/courses/phys522/ γ “Driven damped Harmonic Oscillator”

7. Purdue University Spring 2014 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 6 (2/5/2014) Slide 7yongchen@purdue.edu Introduction to Quantum Optics & Quantum Photonics PHYS522 ECE695 (“Coherent Optics & Quantum Electronics”) http://www.physics.purdue.edu/academic_programs/courses/phys522/ (FS Chap 1)

8. Purdue University Spring 2014 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 6 (2/5/2014) Slide 8yongchen@purdue.edu Introduction to Quantum Optics & Quantum Photonics PHYS522 ECE695 (“Coherent Optics & Quantum Electronics”) http://www.physics.purdue.edu/academic_programs/courses/phys522/ +

9. Purdue University Spring 2014 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 6 (2/5/2014) Slide 9yongchen@purdue.edu Introduction to Quantum Optics & Quantum Photonics PHYS522 ECE695 (“Coherent Optics & Quantum Electronics”) http://www.physics.purdue.edu/academic_programs/courses/phys522/

10. Purdue University Spring 2014 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 6 (2/5/2014) Slide 10yongchen@purdue.edu Introduction to Quantum Optics & Quantum Photonics PHYS522 ECE695 (“Coherent Optics & Quantum Electronics”) http://www.physics.purdue.edu/academic_programs/courses/phys522/ Now move on to quantum (semiclassical) Last quiz: average 30% molecule

11. Purdue University Spring 2014 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 6 (2/5/2014) Slide 11yongchen@purdue.edu Introduction to Quantum Optics & Quantum Photonics PHYS522 ECE695 (“Coherent Optics & Quantum Electronics”) http://www.physics.purdue.edu/academic_programs/courses/phys522/ Semiclassical Light-Matter interaction: Einstein Coefficients (Planck blackbody) (FQ Ch4/FS App-B)

12. Purdue University Spring 2014 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 6 (2/5/2014) Slide 12yongchen@purdue.edu Introduction to Quantum Optics & Quantum Photonics PHYS522 ECE695 (“Coherent Optics & Quantum Electronics”) http://www.physics.purdue.edu/academic_programs/courses/phys522/ Radiative Transition Rates Fermi Golden Rule (DOS of final state: light (photon) +matter [neglect if discrete]) X-polarized:

13. Purdue University Spring 2014 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 6 (2/5/2014) Slide 13yongchen@purdue.edu Introduction to Quantum Optics & Quantum Photonics PHYS522 ECE695 (“Coherent Optics & Quantum Electronics”) http://www.physics.purdue.edu/academic_programs/courses/phys522/ Selection Rules (even/odd)(orbital)

14. Purdue University Spring 2014 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 6 (2/5/2014) Slide 14yongchen@purdue.edu Introduction to Quantum Optics & Quantum Photonics PHYS522 ECE695 (“Coherent Optics & Quantum Electronics”) http://www.physics.purdue.edu/academic_programs/courses/phys522/ “forbidden” transition Metastable state Fluorescence phosphorescence Transition matrix element

15. Purdue University Spring 2014 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 6 (2/5/2014) Slide 15yongchen@purdue.edu Introduction to Quantum Optics & Quantum Photonics PHYS522 ECE695 (“Coherent Optics & Quantum Electronics”) http://www.physics.purdue.edu/academic_programs/courses/phys522/ Also can engineer DOS g to control transition rates! cavityPhotonic crystal (bandgap)/ Metamaterials …

16. Purdue University Spring 2014 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 6 (2/5/2014) Slide 16yongchen@purdue.edu Introduction to Quantum Optics & Quantum Photonics PHYS522 ECE695 (“Coherent Optics & Quantum Electronics”) http://www.physics.purdue.edu/academic_programs/courses/phys522/ Molecules & molecular solids

17. Purdue University Spring 2014 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 6 (2/5/2014) Slide 17yongchen@purdue.edu Introduction to Quantum Optics & Quantum Photonics PHYS522 ECE695 (“Coherent Optics & Quantum Electronics”) http://www.physics.purdue.edu/academic_programs/courses/phys522/ Jablonski Diagram Singlet Triplet SO coupling

18. Purdue University Spring 2014 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 6 (2/5/2014) Slide 18yongchen@purdue.edu Introduction to Quantum Optics & Quantum Photonics PHYS522 ECE695 (“Coherent Optics & Quantum Electronics”) http://www.physics.purdue.edu/academic_programs/courses/phys522/ (X) 1 Σ (2) 1 Σ (2) 3 Σ (1) 3 Σ (3) 1 Σ LIF excitation

19. Purdue University Spring 2014 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 6 (2/5/2014) Slide 19yongchen@purdue.edu Introduction to Quantum Optics & Quantum Photonics PHYS522 ECE695 (“Coherent Optics & Quantum Electronics”) http://www.physics.purdue.edu/academic_programs/courses/phys522/ Heaters Li 550 ̊ C Rb 300 ̊ C Rb 300 ̊ C Cooling water PMT Monochromator λ -meter Molecular Spectroscopy in a heat-pipe ( 7 Li 85 Rb) (A) Laser Induced Fluorescence (LIF) (B) Excitation Spectroscopy Laser LIF Laser

20. Purdue University Spring 2014 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 6 (2/5/2014) Slide 20yongchen@purdue.edu Introduction to Quantum Optics & Quantum Photonics PHYS522 ECE695 (“Coherent Optics & Quantum Electronics”) http://www.physics.purdue.edu/academic_programs/courses/phys522/ Korek et al., Chem Phys 256 1 Laser Induced Fluorescence (LIF) Dutta et al., Chem Phys Lett (2011), doi:10.1016/j.cplett.2011.05.059 From low v’ levels of B 1 Π state

21. Purdue University Spring 2014 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 6 (2/5/2014) Slide 21yongchen@purdue.edu Introduction to Quantum Optics & Quantum Photonics PHYS522 ECE695 (“Coherent Optics & Quantum Electronics”) http://www.physics.purdue.edu/academic_programs/courses/phys522/ Fluorescence from successively higher vib. (1) 1 П states PR v PR

22. Purdue University Spring 2014 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 6 (2/5/2014) Slide 22yongchen@purdue.edu Introduction to Quantum Optics & Quantum Photonics PHYS522 ECE695 (“Coherent Optics & Quantum Electronics”) http://www.physics.purdue.edu/academic_programs/courses/phys522/ Franck-Condon Overlap of Vibronic state

23. Purdue University Spring 2014 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 6 (2/5/2014) Slide 23yongchen@purdue.edu Introduction to Quantum Optics & Quantum Photonics PHYS522 ECE695 (“Coherent Optics & Quantum Electronics”) http://www.physics.purdue.edu/academic_programs/courses/phys522/ Photo-association laser

24. Purdue University Spring 2014 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 6 (2/5/2014) Slide 24yongchen@purdue.edu Introduction to Quantum Optics & Quantum Photonics PHYS522 ECE695 (“Coherent Optics & Quantum Electronics”) http://www.physics.purdue.edu/academic_programs/courses/phys522/ PA rate of 7 Li near FR a > 0a < 0 I = 1.65 W/cm 2 v’’ = 83 T ~ 10  K v’’ = 84 v’’ = 83 v’’ = 82 ~10 4 M.Junker et al., PRL 2008

25. Purdue University Spring 2014 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 6 (2/5/2014) Slide 25yongchen@purdue.edu Introduction to Quantum Optics & Quantum Photonics PHYS522 ECE695 (“Coherent Optics & Quantum Electronics”) http://www.physics.purdue.edu/academic_programs/courses/phys522/ v’’ r r E RcRc 2S 1/2 + 2S 1/2 2S 1/2 + 2P 1/2 Why the zero? f(R c )R~ 2 big small Rate depends on ground state wavefunction (Franck- Condon) Bohn and Julienne PRA 60, 414 (1999).

26. Purdue University Spring 2014 Prof. Yong P. Chen (yongchen@purdue.edu) Lecture 6 (2/5/2014) Slide 26yongchen@purdue.edu Introduction to Quantum Optics & Quantum Photonics PHYS522 ECE695 (“Coherent Optics & Quantum Electronics”) http://www.physics.purdue.edu/academic_programs/courses/phys522/ Next Lecture (8): Light Matter Interaction --- Solids (interband transition) FS Chap 3.