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Magnetic field dependent tunneling in glasses
1Physikalisch-Technische Bundesanstalt, Abbestrasse 2-12, D-10587 Berlin, Germany.
Physical Review Letters
|October 4, 2000
Summary
Quantum effects of electromagnetic flux were observed in barium alumosilicate glass below 100 mK. Dielectric response became sensitive to magnetic fields, showing unexpected behavior and oscillations.
Area of Science:
- Condensed matter physics
- Quantum mechanics
- Materials science
Background:
- Dielectric properties of amorphous solids are typically independent of magnetic fields at low temperatures.
- Quantum tunneling systems in glasses exhibit unique low-temperature behaviors.
Purpose of the Study:
- To investigate the influence of magnetic fields on the dielectric response of barium alumosilicate glass at cryogenic temperatures.
- To explore potential quantum effects related to electromagnetic flux in this material.
Main Methods:
- Experiments conducted below 100 milliKelvin (mK).
- Measurement of dielectric response in the presence of varying magnetic fields.
- Analysis of dielectric saturation and resonant regime oscillations.
Main Results:
- Dielectric response became sensitive to magnetic fields below 100 mK, contrary to expectations.
- Weak magnetic fields lifted dielectric saturation.
- Oscillations in dielectric response were observed in the low-temperature resonant regime.
Conclusions:
- The observed phenomena suggest quantum effects of electromagnetic flux.
- A proposed mechanism involves magnetic induction violating time-reversal invariance, causing flux periodicity in tunneling system energy levels.
- Low-temperature interactions between tunneling systems enhance these effects, making them measurable.
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