introduction to nanomechanics (fall 2010) martino poggio
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Introduction to Nanomechanics(Fall 2010)
Martino Poggio
Introduction to Nanomechanics 2
Equipartition Theorem
05.10.2009 Introduction to Nanomechanics
22
2
1
2
1
2
1xkxmTkB
Tk
kx B2
Tk
kxx B
rms 2
Introduction to Nanomechanics 3
L = 2 mw = 100 mmt = 50 mmESS = 200 GPa
3
3
4L
Ewtk
k = 78 k /N m
Tk
kxx B
rms 2
xrms = 0.2 pm
for T = 300 K
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Introduction to Nanomechanics 4
L = 150 mmw = 40 mmt = 5 mmESi = 169 GPa
3
3
4L
Ewtk
k = 63 /N m
Tk
kxx B
rms 2
xrms = 8 pm
for T = 300 K
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Introduction to Nanomechanics 5
L = 120 mmw = 3 mmt = 100 nmESi = 169 GPa
3
3
4L
Ewtk
k = 73 /mN m
Tk
kxx B
rms 2
xrms = 8 nm
for T = 300 K
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Introduction to Nanomechanics 6
L = 120 mmw = 3 mmt = 100 nmESi = 169 GPa
3
3
4L
Ewtk
k = 73 /mN m
Tk
kxx B
rms 2
xrms = 9 Å
for T = 4.2 K
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Introduction to Nanomechanics 7
3500 3750 4000 4250
1E-5
1E-4
1E-3
0.01
0.1
1
10
100
1000
An
g2 /Hz
Frequency (Hz)
3500 3750 4000
Frequency (Hz)
4250
1000
100
10
1
0.1
0.01
1E-3
1E-4
1E-5
Spre
ctra
l den
sity
(Å2 /
Hz)
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