Charge-carrier transport measurements through single molecules

Charge-Carrier Transport Measurements through

Single Molecules

Cuvillier Verlag Göttingen

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10 ² 10 ³ 10 ⁴ 10 ⁵ 10 ⁶ 10 ⁷ 10 ⁸ 10 ⁹ 10 ¹⁰ 10 ¹¹

Closing

R esistance []

QPC (12.9 k )

Pushing rod distance [a.u.]

b c

M M

a

After application Before application

2465 2455 2455

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Voltage [V]

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-0.9 -0.6 -0.3 0.0 0.3 0.6 0.9

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raw data 25 cycles

+ 0.4 V

- 0.4 V

a b

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Current [nA]

Voltage [V] Counts

c d

Current [nA]

Voltage [V]

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Voltage [V]

S2

S1 S1

S1 S2 & S3

S2 S3 S3

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S

CH ₃

C H ₃

CH ₃

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81

N

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C

S S

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S

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0 5 10 15 20 25 30 35

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-20 0 20 40

0 20 40 60 80 100

Voltage [V]

Current [nA] Diff . Conductance [nS]

Current [nA] Diff . Conductance [nS]

a

b 50 K ^{S S}

2

S S

) cond

250 K

2 ) cond

2

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85

S S

100 200 300 400 500 600 700 800

Co u n ts

Resistance [M W ] B

A

Resistance [M ] S

Counts

V = 5mV

0 100 200 300 400 500 600 700 800 Resistance [M ] S

Counts

10 ⁶ 10 ⁷ 10 ⁸ 10 ⁹ 10 ¹⁰ 10 ¹¹

Pushing rod position approx.

6 pm V = 5mV

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