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Associated Chromosome Trap for Identifying Long-range DNA Interactions
Published on: April 23, 2011
Proximity-induced superconductivity in DNA
A Y Kasumov1, M Kociak, S Guéron
1Laboratoire de Physique des Solides, Associé au CNRS, Bât 510, Université Paris-Sud, 91405, Orsay, France.
Science (New York, N.Y.)
|February 24, 2001
Summary
Double-stranded DNA exhibits ohmic conductivity down to 1 Kelvin. DNA molecules maintain phase coherence over hundreds of nanometers, even at millikelvin temperatures, suggesting potential as molecular wires.
Area of Science:
- Molecular electronics
- Condensed matter physics
- Nanotechnology
Background:
- Understanding the electrical properties of DNA is crucial for molecular electronics.
- Previous studies have explored DNA conductivity with varying results.
- Investigating DNA behavior at cryogenic temperatures is essential for its application in quantum devices.
Purpose of the Study:
- To measure the conductivity of double-stranded DNA molecules at cryogenic temperatures.
- To determine the ohmic behavior and resistance of DNA over a wide temperature range.
- To investigate proximity-induced superconductivity in DNA.
Main Methods:
- DNA molecules were deposited using a combing process across a submicron slit.
- Conductivity measurements were performed between rhenium/carbon metallic contacts.
- Measurements were conducted from room temperature down to 1 Kelvin.
Main Results:
- DNA conduction was found to be ohmic between room temperature and 1 Kelvin.
- The resistance per DNA molecule was less than 100 kilohm and showed weak temperature dependence.
- Proximity-induced superconductivity was observed below the superconducting transition temperature of the contacts.
Conclusions:
- DNA molecules can conduct electricity down to millikelvin temperatures.
- Phase coherence is maintained over several hundred nanometers in DNA molecules.
- These findings support the potential of DNA as a component in cryogenic electronic devices.
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