Physics 344
Foundations of 21
st
Century Physics:
Relativity, Quantum Mechanics and
Their Applications
Their Applications
Instructor:
Dr. Mark Haugan
Office:
PHYS 282
[email protected]
TA:
Dan Hartzler
Office:
PHYS 7
[email protected]
Grader:
Shuo Liu
Office:
PHYS 283
[email protected]
Office Hours: If you have questions, just email us to make an
appointment.
We enjoy talking about physics!
appointment.
Notices:
Midterm II at 8:00pm, Thursday, December 2 in MSEE B012

This
** preview**
has intentionally

**sections.**

*blurred***to view the full version.**

*Sign up*
The Energy of Cavity Fields
Last lecture we began the wave-model analysis of the distribution of field energy
stored in a resonant cavity in order to complete our blending of the wave and
photon models of light into a quantum mechanics of single photon states of the
electromagnetic field.
Recall that we can represent generic cavity fields as superpositions of modal
1
( , )
sin(
)sin(
)
y
n
n
n
n
n
E
x t
E
k x
t
ω
δ
∞
=
=
+
∑
fields, each with their own amplitude and phase,
(
)
n=1
sin(
)
sin(
)
cos(
)
n
n
n
n
n
k x
t
t
α
ω
β
ω
∞
≡
+
∑
with
or, equivalently,
cos(
)
n
n
n
E
α
δ
=
and
sin(
)
n
n
n
E
β
δ
=
∞
∑
2
2
2
n
n
n
E
α
β
=
+
and
tan(
)
n
n
n
α
δ
β
=
(
)
1
( , )
cos(
)cos(
)
cos(
)
cos(
)
sin(
)
z
n
n
n
n
n
n
n
n
n
n
cB
x t
E
k x
t
k x
t
t
ω
δ
α
ω
β
ω
=
∞
=
+
≡
−
∑
n=1