Magnetic-field-dependent thermodynamics ofMn12-acetate single crystals at low temperatures

We report measurements of out-of-plane (ρ c ) and in-plane (ρab) normal-state resistivities of single crystals of insulating PrBa2Cu3O 7-δ and strongly underdoped oxygen deficient YBa2Cu3O 6.41 using a flux transformer method. In the superconducting specimens, the onset of superconductivity was suppressed by a magnetic field of 9 T. We have found that the anisotropy ρc/ρab of these samples increases monotonically at low temperatures with no signs of saturation. The temperature dependence of ρc/ρab for YBa2Cu3O6.41 is well described by ρc/ρab=a +bT-2/3, but over a smaller temperature range than for insulating PrBa2Cu3O 7-δ. Both the absence of saturation of ρc/ρab and its T-2/3 dependence indicate two-dimensional conduction. This means that the average in-plane hopping distance of the localized charge carriers increases with decreasing T according to Mott's [Formula: see text] law, while the elementary step in the c-direction remains T independent, equal to the spacing between the bilayers.

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Structure in the magnetic-field-dependent microwave absorption of Bi-Sr-Ca-Cu-O single crystals

Physical Review B ◽

10.1103/physrevb.39.808 ◽

1989 ◽

Vol 39 (1) ◽

pp. 808-810 ◽

Cited By ~ 14

Author(s):

E. J. Pakulis ◽

G. V. Chandrashekhar

Keyword(s):

Magnetic Field ◽

Single Crystals ◽

Microwave Absorption ◽

Field Dependent ◽

The Magnetic Field

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Synthesis and Magnetic Properties of β-Cu3Fe4(VO4)6 Single Crystals

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.233-234.137 ◽

2015 ◽

Vol 233-234 ◽

pp. 137-140

Author(s):

Dmitry A. Balaev ◽

Oleg A. Bayukov ◽

Evgeniy V. Eremin ◽

M.S. Molokeev ◽

Anatoly I. Pankrats ◽

...

Keyword(s):

Magnetic Field ◽

Magnetic Properties ◽

Single Crystal ◽

Spin Glass ◽

Single Crystals ◽

Low Temperatures ◽

Freezing Temperature ◽

X Ray ◽

Glass State ◽

The Magnetic Field

β-Cu3Fe4(VO4)6 single crystals were synthesized. The X-ray, magnetic, Mössbauer, and EPR investigations of the crystals were fulfilled. It is established that single-crystal β-Cu3Fe4(VO4)6 is a spin glass at low temperatures. Freezing temperature varies considerably depending on the orientation of the magnetic field relative to the crystal axes. Spin-glass state is confirmed by the relaxation of the magnetization.

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Temperature and Magnetic Field Dependent Photoluminescence from Carbon Nanotubes

International Journal of Modern Physics B ◽

10.1142/s0217979207042616 ◽

2007 ◽

Vol 21 (08n09) ◽

pp. 1180-1188 ◽

Cited By ~ 1

Author(s):

R. J. Nicholas ◽

I. B. Mortimer ◽

L. J. Li ◽

A. Nish ◽

O. Portugall ◽

...

Keyword(s):

Magnetic Field ◽

Carbon Nanotubes ◽

Carbon Nanotube ◽

Luminescence Intensity ◽

Low Temperatures ◽

Energy Splitting ◽

Tube Axis ◽

Small Energy ◽

Single Walled Carbon Nanotube ◽

Field Dependent

Photoluminescence as a function of temperature and magnetic field from single walled carbon nanotube solutions is described. This is modelled assuming that it is dominated by the small energy splitting between the dark and bright states of the singlet excitons which are found to be in the region of 1-5 meV for nanotubes of 0.8-1.2nm. The emission energies show a large red-shift due to the introduction of an Aharanov-Bohm phase by magnetic field along the tube axis and the luminescence intensity is strongly enhanced at low temperatures due to the mixing of the different valley states of the excitons.

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STRUCTURAL AND MAGNETIC FIELD DEPENDENT TRANSPORT PROPERTIES OF p-MnxGe1-x/n-Ge HETEROJUNCTION

International Journal of Modern Physics B ◽

10.1142/s0217979209063006 ◽

2009 ◽

Vol 23 (17) ◽

pp. 3579-3585

Author(s):

SANDIP MAJUMDAR ◽

AMAL KUMAR DAS ◽

SAMIT KUMAR RAY

Keyword(s):

Magnetic Field ◽

Low Temperature ◽

Transport Properties ◽

Low Temperatures ◽

Impurity Band ◽

Heterojunction Diode ◽

Field Dependent ◽

Current Rectification ◽

Dependent Transport ◽

Mn Doped

We report the study of a promising Ge -based magnetic heterojunction diode composed of a Mn -doped p - Ge film grown on lightly doped n - Ge film. Magnetic field dependent current rectification of the diode occurs at a low temperature. The measurements of resistivity and magnetoresistance in plane at low temperatures reveal the presence of impurity band in Ge due to Mn doping.

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