Mondays and Wednesdays, 13:00 to 14:15 pm
PAIS Room 1160
Fall 2023
Instructor
Jean-Claude Diels
Physics & Astronomy room PAIS 2236
phone 277 4026
CHTM, room 114A, phone 272 7830
email: jcdiels@unm.edu
Teaching Assistant
Elaheh Zamani ezamani@unm.edu
Reference material
Lectures summary, homework assignments will be posted on dielslab.unm.edu.
Possibly the only reference book written by an experimentalist – I would call it the Laser Holy Book – is: LASERS, by Anthony E. Siegman, University Press.
Other references:
- Laser electronics, J.Y Verdeyen, Prentice Hall
- Solid state laser engineering, W. Koechner, Springer verlag
- Photonics, Saleh
Assignments
Homework problems will be assigned on a regular base, due generally on Wednesdays. They will count for 40% of the final grade.
Some problems will be treated in class.
Exams
One midterm and one final; 30% of grade each.
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Please note: the following two lines are links
Syllabus
INTRODUCTION
This introduction (power point link) contains some general insructions, syllabus, a (naive) introduction on waves, complex representation of the fields, wave addition leading to interference and coherent versus incoherent wave addition.
Wave addition leads to energy conservation, which leads to a phase relation between any reflected and transmitted wave by an optical system.
Simplest phenomenon with waves. Not so simple. Even the Duck pound wave, or the acoustic wave, can show a transverse Doppler shift.
The transverse Doppler shift with light leads us to the Lorentz transformation.
Next introductory topic: the extreme dynamic range of laser light properties.
dynamic range of laser light properties
The ppt file above contains a few slides about the photon , its linear and angular momentum, radiation pressure, highest power/intensities achieved.
There is a phase shift in a rotating ring resonator between th light circulating in the sense of rotation, and the counter-circulation beam. Sagnac interpreted his measurement as a proof of the existence of ether.
Today the shift is explained by relativity (the Lorentz transformation).
However, if the ring is an active laser instead of a passive resonator, the Sagnac phase shift can be measurred as a beat frequency (= phase shift divided by cavity round-trip time. 3 classical interpretations are given for that beat frequency.
Reading material: TIme dilation length contraction, Lorentz transformation, from Forshaw, J.R.; Smith, A.G. Dynamics and Relativity; JohnWiley & Sons Ltd.: New York, NY, USA, 2009; pp. 124–126.
REVIEW OF MAXWELL'S EQUATIONS
Lecture 9-6-2023
Reading material: Maxwell step by step
Dipole emission - Polarization
"Linear polarization" but ... frequency dependent --> transient response
Laser-Matter interaction: Polarization from a 2 level system
From transient to steady state: rate equations, linear response
Lecture 9-11-2023:
Fourier Review and 2-level systems (updated 9/21)
Reading material: Semi-classical interaction
Einstein coefficients and blackbody radiation Lecture 9-27-23
Rate equations
In the following ppt files:
Parameters of rate equations how they are connected. / Maxwell’s equations versus Einstein coefficients / Defying reciprocity in optics / Power broadening, homogeneous broadening inhomogeneous broadening / Creating an inversion with rate equations / Saturation, self saturation, mutual saturation / Design amplifiers
Rate equations - short vs long relax
Broadening-rate equations III-Oct9
Next ppt file: Sample laser problem / More on saturation: induced gratings / Saturation of inhomogeneous broadened lines
Reading material: the oscillator model - Homogeneous and inhomogeneous broadening
Fabry-Perot Etalon
Gaussian beams
Qualitative introduction on the formation of Gaussian beams in a laser cavity: Introduction
Derivation of the q complex parameter - Application of the ABCD matrices to the evolution of 1/q: Gaussian-q
Gaussian beams - cavity stability - space-time analogy
The Gaussian solution of Maxwell's equation is an approximation of a more general paraxial approximation, in which the wavefronts and envelope of rays make families of confocal ellipsoids and hyperbooids.
Reading: Confocal parameter
Gaussian cavities - "equilibrium" and "stability" in space and time. More Gaussian-space-time including longitudinal and transverse modes.
Modes and lasers
Single mode gas lasers; He-Ne laser, laser gyro, multimode solid state lasers, single mode Q-switch by injection seeding, injection lock-in in laser gyros.
Mode-locking
Pulse parameters for high field experiments – introducing the CEP. Single pulse --- the CEP and the uncertainty principle. Defining and controlling the CEP.
Measuring the CEO. ppt file of Nov 13
Some laser systems
Some comments about HW5, Kramers-Kronig, November22
Laser examples (CO2, ion lasers, AO modulators, excimer lasers)
Pre-mid term test review
HOMEWORK
hOMEWORK 1: Illustration of Doppler shift and radiation pressure
Homework 2: Fourier transforms
Homework 5 and solution