相关论文: Axion Detection with Quantum Hall Effect
Axion dark matter inevitably generates electromagnetic radiation in quantum Hall effect experiments that use strong magnetic fields. Although these emissions are very weak, we have shown using a QCD axion model that they influence the…
Axion dark matter is converted to electromagnetic radiations in the presence of strong magnetic field. The radiations possibly give rise to non trivial phenomena in condensed matter physics. Especially, we discuss that saturation of…
We propose a new method for detecting dark matter axions using a resonant cavity coupled with a quantum Hall system. When a small sample exhibiting quantum Hall effect is placed inside the cavity and the cavity is tuned to resonance,…
If the symmetry breaking inducing the axion occurs after the inflation, the large axion isocurvature perturbations can arise due to a different axion amplitude in each causally disconnected patch. This causes the enhancement of the…
Dark matter axions may cause transitions between atomic states that differ in energy by an amount equal to the axion mass. Such energy differences are conveniently tuned using the Zeeman effect. It is proposed to search for dark matter…
The quantum Hall plateau transition was studied at temperatures down to 1 mK in a random alloy disordered high mobility two-dimensional electron gas. A perfect power-law scaling with \kappa=0.42 was observed from 1.2K down to 12mK. This…
The amplitude of the pseudoscalar (axion) or scalar field fluctuates on a time scale of order of million field oscillation periods which is a typical coherence time in the virialized axion galactic dark matter halo model. This causes…
The phase transitions from one plateau to the next plateau or to an insulator in quantum Hall and quantum anomalous Hall (QAH) systems have revealed universal scaling behaviors. A magnetic-field-driven quantum phase transition from a QAH…
We theoretically consider disorder and temperature effects on the integer quantum Hall effect (IQHE) using a variety of distinct and complementary analytical and numerical techniques. In particular, we address simple, physical, and…
The temperature of baryons at the end of the cosmic dark ages can be inferred from observations of the 21-cm hyperfine transition in neutral hydrogen. Any energy injection from the dark sector can therefore be detected through these…
We report low temperature electronic transport results on the fractional quantum Hall effect of composite fermions at Landau level filling nu = 4/11 in a very high mobility and low density sample. Measurements were carried out at…
When axion cold dark matter interacts with a static magnetic field, it can be converted to photons with energy near the axion's mass. Classical analysis shows that incorporating a resonant cavity significantly enhances this conversion rate,…
We report the observation of TEMPERATURE-INDUCED transitions between insulator, metal, and quantum-Hall behaviors for transport coefficients in the very dilute high mobility two-dimensional electron system in silicon. We consider the…
Current techniques cannot detect axion dark matter over much of its parameter space, particularly in the theoretically well-motivated region where the axion decay constant f_a lies near the GUT and Planck scales. We suggest a novel…
Non-virialized dark-matter axions may be present in the Milky Way halo in the form of low-velocity-dispersion flows. The Axion Dark Matter eXperiment performed a search for the conversion of these axions into microwave photons using a…
We report ultra-low temperature experiments on the obscure fractional quantum Hall effect (FQHE) at Landau level filling factor $\nu$=5/2 in a very high mobility specimen of $\mu=1.7 \times 10^7$ cm$^2$/Vs. We achieve an electron…
The temperature and scale dependence of resistivities in the standard scaling theory of the integer quantum Hall effect is discussed. It is shown that recent experiments, claiming to observe a discrepancy with the global phase diagram of…
The axion thermalization rate is a crucial input to determine the hot dark matter bound of axions, resulting from the scattering processes in the thermal bath of early Universe. We demonstrate that the commonly employed axion thermalization…
Our study presents experimental measurements of the contact and longitudinal voltage drops in Hall bars, as a function of the current amplitude. We are interested in the heating phenomenon which takes place before the breakdown of the…
Precision measurements of the Hall effect have been carried out for both archetypal heavy fermion compound - CeCu6 and exemplary solid solutions CeCu6-xAux (x= 0.1 and 0.2) with quantum critical behavior. The experimental results have been…