Technique for magnetic susceptibility determination in the highly doped semiconductors by electron spin resonance

Abstract

Low temperature transformation from antiferromagnetic to ferromagnetic order in impurity system Ge:As near the insulator-metal phase transition AIP Conference Proceedings 1610, 129 (2014) A method for determining the magnetic susceptibility in the highly doped semiconductors is considered. It is suitable for the semiconductors near the metal -insulator transition when the conductivity changes very quickly with the temperature and the resonance line form distorts. A procedure that is based on double integration of the positive part of the derivative of the absorption line having a Dyson shape and takes into account the depth of the skin layer is described. Analysis is made for the example of arsenic-doped germanium samples at a rather high concentration corresponding to the insulator-metal phase transition

Determination of the Diamagnetic and Paramagnetic Impurity Magnetic Susceptibility in Ge:As near the Metal Insulator phase Transition

“…We explain such behavior by transition from antiferromagnetic to ferromagnetic spin coupling at low temperatures [2,6].…”

“…Magnetic susceptibility was measured on a series of samples Ge:As, which had been used before in papers [2][3][4]. Phased reduction of electron concentration compared to original value for a series of samples ~3.6 х 10 17 cm -3 was performed on account of introducing compensation impurity Ga during transmutation neutron doping.…”

“…It enables to define only paramagnetic component of impurity susceptibility χ IР . A strong influence of spin the interaction near the metal-insulator phase transition (MI transition) in Ge:As [2][3][4] Using both SQUID and ESR methods we would like to define behavior of the impurity diamagnetic susceptibility χ ID and influence of spin interaction on it.…”

Low-temperature ordering caused by exchange interaction in the Si:P impurity system near the insulator - Metal phase transition

“…Figure 2 shows the absorption line at two temperatures: low, when the sample has a high resistance, and high, when the conductivity exerts a decisive influence on the line shape. We used in the latter case the procedure described in [9]. 18 cm -3 at temperatures of (1) 2.6 and (2) 80 K.…”

“…Studies of the magnetic properties of Ge:As near the IM phase transition [6][7][8] proved to be considerably more informative because a procedure for sample compensation by transmutation neutron doping was used. This made it possible to examine the magnetic properties of the material on a set of samples with the spin concentration varied in small steps and to demonstrate that the magnetic susceptibility χ p depends in this set not only on temperature, but also on the spin concentration and sample compensation.…”