scholarly journals Transmission and tunneling probability in two-band metals: Influence of magnetic breakdown on the Onsager phase of quantum oscillations

2017 ◽  
Vol 43 (2) ◽  
pp. 173-185 ◽  
Author(s):  
Jean-Yves Fortin ◽  
Alain Audouard
Keyword(s):  
Tunneling Probability ◽  
Quantum Oscillations ◽  
Magnetic Breakdown

THE STUDY OF THE MAGNETIC BREAKDOWN EFFECT AS A FUNCTION OF ANGLE IN THE ORGANIC CONDUCTOR K- (BEDT-TTF)2Cu(NCS)2 IN HIGH MAGNETIC FIELDS

2002 ◽  
Vol 16 (20n22) ◽  
pp. 3355-3359
Author(s):  
I. MIHUT ◽  
C. C. AGOSTA ◽  
C. H. MIELKE ◽  
M. TOKOMOTO
Keyword(s):  
Magnetic Field ◽  
Magnetic Fields ◽  
Spin Splitting ◽  
High Magnetic Fields ◽  
Organic Conductor ◽  
Cross Sectional ◽  
Tank Circuit ◽  
Quantum Oscillations ◽  
Magnetic Breakdown ◽  
Splitting Factor

The magnetic breakdown effect can be seen by the growth of new frequencies in the quantum oscillations in clean metals as a function of magnetic field. We have studied the variation of the amplitudes in the quantum oscillations in the resistance (the Shubnikov-de Haas effect) as a function of angle in the quasi-two dimensional-organic conductor κ-(BEDT-TTF)2Cu(NCS)2. The measurements were made by means of a radio frequency (rf) tank circuit (~ 50 MHz) at very high magnetic fields(50T-60T) and low temperature(500 mK). The geometry of the rf excitation we used excited in-plane currents, and therefore we measured the in-plane resistivity. In contrast to conventional transport measurements that measure the inter-plane resistivity, the in-plane resistivity is dominated by the magnetic breakdown frequencies. As a result we measured much higher breakdown frequency amplitudes than conventional transport experiments. As is expected, the angular dependence of the Shubnikov-de Haas frequencies have a 1/cosθ behavior. This is due to the change of the cross sectional area of the tubular Fermi surface as the angle with respect to the magnetic field is changed. The amplitude of the oscillations changes due to the spin splitting factor which takes into account the ratio between the spin splitting and the energy spacing of the Landau levels which also has 1/cosθ behavior. We show that our data agree with the semi-classical theory (Lifshitz-Kosevich formula).

scholarly journals Quantum oscillations, magnetic breakdown and thermal Hall effect in Co3Sn2S2

2021 ◽  
Author(s):  
Linchao Ding ◽  
Jahyun Koo ◽  
Changjiang Yi ◽  
Liangcai Xu ◽  
Huakun Zuo ◽  
...  
Keyword(s):  
Hall Effect ◽  
Quantum Oscillations ◽  
Magnetic Breakdown

A study of the quantum oscillations in the thermopower of molybdenum

1982 ◽  
Vol 60 (2) ◽  
pp. 122-130 ◽  
Author(s):  
R. Fletcher
Keyword(s):  
Liquid Helium ◽  
Field Dependence ◽  
Large Amplitude ◽  
Experimental Results ◽  
Quantum Oscillations ◽  
Magnetic Breakdown ◽  
Good Agreement

This paper is concerned with quantum oscillations in the thermoelectric coefficients of metals which do not undergo magnetic breakdown, and in particular focuses on the compensated metal Mo. An expression for the amplitude of the oscillations in the thermopower has been developed and is tested using a detailed set of experimental results on Mo taken with [Formula: see text] over the range 1.5–8 T at liquid helium temperatures. Good agreement is obtained for the temperature and field dependence, and absolute amplitudes are predicted to within a factor near unity. Oscillations of appreciable amplitude arc neither expected nor observed in the Nernst–Ettingshausen (N.E.) coefficient of Mo. Available thermopower data on In have also been analysed; it is concluded that, contrary to a previous speculation. In does not undergo magnetic breakdown at fields of the order of 2 T. It is suggested that, contrary to the thermopower. the N.E. coefficient will provide an unambiguous test for the occurrence of breakdown in metals since it is expected to exhibit large amplitude quantum oscillations only under breakdown conditions.

scholarly journals Quantum Oscillations from Nodal Bilayer Magnetic Breakdown in the Underdoped High Temperature SuperconductorYBa2Cu3O6+x

2012 ◽  
Vol 108 (19) ◽  
Author(s):  
Suchitra E. Sebastian ◽  
N. Harrison ◽  
Ruixing Liang ◽  
D. A. Bonn ◽  
W. N. Hardy ◽  
...  
Keyword(s):  
High Temperature ◽  
Quantum Oscillations ◽  
Magnetic Breakdown

Anomalous effect of magnetic breakdown on the oscillatory magnetization

1985 ◽  
Vol 400 (1818) ◽  
pp. 145-161 ◽  
Keyword(s):  
Orbit Interaction ◽  
Energy Band Structure ◽  
Field Amplitude ◽  
Conventional Theory ◽  
Anomalous Effect ◽  
Quantum Oscillations ◽  
Magnetic Breakdown ◽  
Field Modulation ◽  
The Magnetic Field ◽  
Good Agreement

It is shown that the effect of magnetic breakdown on the oscillatory magnetization in metals can vary dramatically from that predicted by conventional theory. We report a detailed study of the amplitude of the de Haas–van Alphen (d. H. v. A.) magnetization of the magnetic breakdown β orbit in aluminium, which exhibits unexpected behaviour as a function of the magnitude and orientation of the magnetic field. Amplitude measurements have been made by using a sensitive field-modulation technique in which the interference, in particular, from quantum oscillations in the conductivity, could be reliably separated out. A generalized model for the effect of magnetic breakdown on the amplitude has been developed to explain these results. Calculations of the amplitude based on this model, with the use of breakdown fields deduced from an energy band structure including the spin–orbit interaction, are found to be in good agreement with experiment. The new model indicates that when breakdown is important, the d. H. v. A. frequency is not determined in general by an extremal cross section of the Fermi surface, as is conventionally assumed.

High Field Magnetoresistance and Quantum Oscillations in Iron Whiskers

1975 ◽  
Vol 53 (3) ◽  
pp. 284-298 ◽  
Author(s):  
M. A. Angadi ◽  
E. Fawcett ◽  
Mark Rasolt
Keyword(s):  
Fermi Surface ◽  
High Field ◽  
Quantum Oscillations ◽  
Hole Pocket ◽  
Strain Dependence ◽  
Magnetic Breakdown ◽  
Minority Spin ◽  
Iron Whiskers ◽  
Lower Frequencies

[100] and [111] iron whiskers were measured to determine the origin of open orbits responsible for anisotropy of the high field magnetoresistance. The marked strain dependence of the minima resulting from [Formula: see text] open orbits permits their unambiguous identification as resulting from magnetic breakdown at a symmetry degeneracy, de Haas–Shubnikov oscillations were observed, and complementary de Haas–van Alphen measurements showed the lower frequencies (in the range 1.2–1.5 MG) to correspond to a hole pocket of the minority spin Fermi surface.

Sign in / Sign up

Export Citation Format

Share Document