lecture15

lecture15 - LIGHT-MATTER INTERACTION Two-level atom in an...

Info iconThis preview shows pages 1–6. Sign up to view the full content.

View Full Document Right Arrow Icon
Two-level atom in an optical resonator hv o = E 2 -E 1 Three forms of interaction: Spontaneous emission Absorption Stimulated emission LIGHT-MATTER INTERACTION Book: 13.3 E 2 E 1  f N 2 N 1 Density of photon states
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
SPONTANEOUS EMISSION OF PHOTONS Wiki Spontaneous emission: 1 ph is added to EM field Transition is independent of the number of photons in the mode Occurs randomly - emitted photons are not in phase, incoherent, with no directionality
Background image of page 2
2 2 AN dt dN ) E E ( AN ) E E ( dt dN 1 2 2 1 2 2 E 2 E 1  f N 2 N 1 SPONTANEOUS EMISSION OF PHOTONS Optical power emitted, per unit volume Downward process Einstein’s A coefficient [A] : 1/s
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Absorption of photons Einstein’s B coefficient, B 12 [B 12 ] : m 3 /s Optical power absorbed, per unit volume f N B dt dN 1 12 1 ) E E ( f N B ) E E ( dt dN 1 2 1 12 1 2 1 E 2 E 1  f N 1 N 2 LIGHT-MATTER INTERACTION: ABSORPTION Upward process
Background image of page 4
f N B dt dN 2 21 2 ) E E ( f N B ) E E ( dt dN 1 2 2 21 1 2 2
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 6
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 14

lecture15 - LIGHT-MATTER INTERACTION Two-level atom in an...

This preview shows document pages 1 - 6. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online