Unexpected additional damping of magnetic quantum oscillations in layered organic conductors in tilted magnetic fields

ABSTRACTIn this work, we report the results of studies of the transverse magnetoresistance (MR) of single-crystal Bi nanowires with diameter d<80 nm. The single-crystal nanowire samples were prepared by the Taylor-Ulitovsky technique. Due to the semimetal-to-semiconductor transformation and high density of surface states with strong spin-orbit interactions, the charge carriers are confined to the conducting tube made of surface states. The non monotonic changes of transverse MR that are equidistant in a direct magnetic field were observed at low temperatures in a wide range of magnetic fields up to 14 T. The period of oscillations depends on the wire diameter d as for the case of longitudinal MR. An interpretation of transverse MR oscillations is presented.

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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

International Journal of Modern Physics B ◽

10.1142/s0217979202014401 ◽

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).

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Magnetic Quantum Oscillations in Nanowires

Physical Review Letters ◽

10.1103/physrevlett.95.076601 ◽

2005 ◽

Vol 95 (7) ◽

Cited By ~ 25

Author(s):

A. S. Alexandrov ◽

V. V. Kabanov

Keyword(s):

Quantum Oscillations ◽

Magnetic Quantum Oscillations

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Magnetic quantum oscillations in doped antiferromagnets

International Journal of Modern Physics B ◽

10.1142/s0217979217450151 ◽

2017 ◽

Vol 31 (25) ◽

pp. 1745015

Author(s):

V. V. Kabanov

Keyword(s):

Magnetic Field ◽

Polar Angle ◽

Two Dimensional ◽

Plane Angle ◽

Arbitrary Direction ◽

Magnetization Direction ◽

Quantum Oscillations ◽

Out Of Plane ◽

Plane Direction ◽

Magnetic Quantum Oscillations

Energy spectrum of electrons (holes) doped into two-dimensional (2D) antiferromagnetic (AF) semiconductors is quantized in an external magnetic field of arbitrary direction. A peculiar dependence of de Haas–van Alphen (dHvA) magneto-oscillation amplitudes on the azimuthal in-plane angle from the magnetization direction and on the polar angle from the out-of-plane direction is found. The angular dependence of the amplitude is different if the measurements are performed in the field above and below of the spin-flop field.

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