Abstract
Precision measurements of the quantum Hall resistance
with alternating current (ac) in the kHz range were
performed on epitaxial graphene in order to assess its
suitability as a quantum standard of impedance. The
quantum Hall plateaus measured with alternating current
were found to be flat within one part in 107. This is
much better than for plain GaAs quantum Hall devices and
shows that the magnetic-flux-dependent capacitive ac
losses of the graphene device are less critical. The
observed frequency dependence of about -8?×?10-8/kHz is
comparable in absolute value to the positive frequency
dependence of plain GaAs devices, but the negative sign
is attributed to stray capacitances which we believe can
be minimized by a careful design of the graphene device.
Further improvements thus may lead to a simpler and more
user-friendly quantum standard for both resistance and
impedance.
| Original language | English |
|---|---|
| Article number | 073511 |
| Number of pages | 4 |
| Journal | Applied Physics Letters |
| Volume | 105 |
| Issue number | 7 |
| DOIs | |
| Publication status | Published - 2014 |
| MoE publication type | A1 Journal article-refereed |
Keywords
- graphene
- semiconductors
- electrical resistivity
- quantum measurement theory
- alternating current