Download Modern Optics PHY485F/1485F www.physics.utoronto.ca/~phy485

Modern Optics
PHY485F/1485F
www.physics.utoronto.ca/~phy485/ModOpt/
Robin Marjoribanks
McLennan Physics 1104C
[email protected]
What makes this course
important?
foundation course in modern (quantum) optics
basic literacy in a modern, active area of physics
fundamental science, concepts, understanding
a subject of technology that supports many others
an extremely active, intense area of current
research
numerous Nobel prizes in the last decade
Topics
 laser as a pivot-point
 look backwards from invention to classical optics
needed to understand how the laser tailors light,
 forward to the quantum optics explosion that has
followed
 basic optics
 diffraction theory
 gaussian beams
 laser resonators
 semiclassical laser theory
 ultrafast pulse generation
 a selection of currently active research topics:
 laser cooling, photonic bandgap structures, extreme
optics, quantum information and other topics
The Laser Oscillator
Laser oscillators are built in a Fabry-Perot resonator
W. Silvfast
http://cord.org/step_online/st1-5/st15ttl.htm
 solutions are standing waves in this laser cavity
 spectrum of possible frequencies satisfy:
wn = n 2π c / L
= n wo
L is the cavity length
c is speed of light
 these modes may each have their own amplitude En
thus the optical field in the cavity can be written:
En ei(nwot+f(n))
In a free cavity, with random f(n), we get ‘wild’ light. In a cavity where
we make f(n)=0, we lock the modes together
Ultrafast Ti:sapphire laser
 Kerr effect makes intense pulses ‘self-focus’ slightly




intense pulses pass better through aperture, where weak ones blocked
alters stability of cavity slightly, favoring intense pulses
also can affect deflection of beam, to same effect
modelocking can start from mechanical vibration: ‘magic modelocking’
Er-fiber laser
(Modern Physics Lab PHY326/426)
output:
1550 nm
100 fs
2–40 mW
pump:
980 nm diode
60 mW min
fiber coupled
modelocking:
Kerr ellipserotation
polarizer
discrimination
dispersion
2 kinds of fiber
opposite GVD
pump input coupler
(WDM 980/ 1550nm )
optical pump
(980nm diode laser)
pigtail fiberoptic leads
pigtail fiberoptic leads
Er-doped fiber
(5m length)
pigtail fiberoptic leads
polarization
controller
Faraday
isolator/polarizer
polarization
controller
pigtail fiberoptic leads
pigtail fiberoptic leads
output coupler
Controller for thermoelectric cooler on pump
partial recompression
MetroCor fiber length
electrical feedthroughs
fiber optic feedthroughs
Course Approach
multiple resources:
textbook
lectures
online materials: demos, applications
office hours
other texts
study/work groups
all are needed
each has particular advantages
Lectures
will concentrate on what lectures do best
won’t just lead you through the textbook
will provide interaction and feedback that
books cannot
will provide demonstrations and
animations
will depend on you having read/prepared
also
Textbook
“Optics” (4th edition), Hecht
we’ll use this for its wonderful illustrations
and applications, but it is organized by
device rather than by principle — we’ll use it
for its modules, as we proceed more logically
(see guide to topics on website)
optional (cheap): “Introduction to Modern
Optics” by Grant R. Fowles (get online
errata correcting a number of errors)
reference: “Lasers” by P.W. Milonni and
J.H. Eberly (Wiley).
Office Hours
Professor Marjoribanks
Wednesdays 2–3 pm (OK?)
MP1104C
markers to be determined
Contact
I’ll initiate email using only your official
registered U of T email address (e.g.,
[email protected])
problem set changes, class
announcements, reminders may go there
you’re responsible for email
Problem sets
Problem set due dates (posted on web)
PS#1 - due 2 October
PS#2 - due 21 October
Midterm Test: 28 October 2008, 5-7 pm OK?
PS#3 - due 13 November
PS#4 - due 4 December (zero extensions)
Group seminar presentations 22 November 10-5pm
solutions posted on course web-site
late policy: 20% off per day
zero, once solutions are posted (~3 days)
getting Midterm back
the TAs each mark part of the midterm
I am at a conference the third week of November
 if the TAs don’t both get their marking done in
one week, you won’t get the midterm back before
the start of December
Marking scheme
Term work:
4 problem sets (best 3 out of 4)
30%
seminar group presentation (22 Nov) 10%
term test
60%
100%
Final exam
final exam
Course mark:
100%
60/40 flip-flop
Midterm test – only impossibles
27 Monday 28 Tues
9-10
10-11
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11-12
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29 Wed
30 Thurs
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31 Friday
12-1pm
1-2
2-3
3-4
2
4-5
2
5-6
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8
2
6-7
3
8
3
7-8
8-9
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2
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Colloq
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