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Concentration dependence of the Curie constant and parameters of the localized spins of the nickel impurities in crystals of HgSe

T.E.Govorkova, V.I.Okulov, G.A.Al’shanskii, A.T.Lonchakov, A.F.Gubkin Institute for Metal Physics, Russian Academy of sciences, Ural Branch, Ekaterinburg, Russia

L.D.Paranchich, M.A.AndriichukChernovtsy National University, Chernovtsy, Ukraine

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Outline

1) Impurity levels of transition elements in semiconductors AIIBVI.

2) Description on the concentration dependence of the Curie constant of the hybridized states and its experimental substantiation

(Hg1-xFexSe).

3) Determining spin of cobalt impurity in mercury selenide.

4) Magnetic susceptibility and the electron density in Hg1-xNixSe.

5) Temperature dependence of the magnetic susceptibility of Hg1-xNixSe (experiment).

6) Determining spin of nickel impurity in mercury selenide.

7) Parameters of the localized spins of the 3d-impurities (Fe, Co, Ni)in crystals of mercury selenide.

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Impurity levels of transition elements in semiconductors AIIBVI

HgTe:Mn, HgSe:Mn

состояния иона Mn3+ в валентной полосе

ZnSe:3d, ZnO:3d

d-состояния в запрещенной полосе

HgSe:3d

d-уровень в полосе проводимости

1) 2) 3)

1) 2) 3)

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Magnetic moments of the impurity atoms of transition elements (Fe, Co) in mercury selenide

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The Physics of Metals and Metallography, 2009, v. 108, № 2, pp.116-119.

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Description on the concentration dependence of the Curie constant of the hybridized states and its experimental substantiation

,n)S(aC iio ,nn igi

where the coefficient is determined by the known formula

)S(a

,k/)S(S)S(a 314 20

0 is the Bohr magneton, is the Boltzmann constant,k

/nnig 0

,n)S(aC ii .nn igi

),nn)(S(an)S(aC igiiigio .nn iig

).nn)(S(an)S(aC iiio 00

:Fe 1 .nn di Parameters (ν = 1):

Sio= 5/2, n0d = 2.6·1018cm-3.

SeFeHg xx1

12.Si

1)

2)

3)

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Parameters (ν=1):Sio= 2, n0d = 2.2 ·1018cm-3;

(ν=2):Sio= 5/2, n0d= 0.5 ·1018cm-3

Determining spin of cobalt impurity in mercury selenide

)nn)(S(an)S(aC igiiigio

:Co 1 2

SeCoHg xx1

318105 cmnCo 521.Si

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Parameters of the hybridized states of the 3d-impurities (Fe, Co)in crystals of mercury selenide

ionelectronic

configurationtype of the impurity

ν Sio Si

nod , 1018cm-3

Fe2+ 3d6 donor 1 5/2 2.1±0.1 2.6

Co2+ 3d7 donor 2 5/2 1.52±0.06 0.5

In this work we gave an experimental substantiation of the earlier-suggested formula for describing the concentration dependence of the Curie constant in the paramagnetic susceptibility of donor impurities with hybridized electronic states in the conduction band. As a result of an analysis of the data on the Curie constant in the magnetic susceptibility of the iron (cobalt) impurities in HgSe, the values of the effective spins of impurities and the resonance concentration of donor electrons have been obtained.

SeFeHg xx1

SeCoHg xx1

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Magnetic susceptibility of HgSe:Ni speciments vs temperature

Izvestiya Vysshikh Uchebnykh

Zavedenii, 1990, № 11, pp.44-47.

SeNiHg xx1

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Dependence of the electron density in HgSe:Ni on the concentration of nickel atoms (T = 4.2K)

Resonant states formed by cobalt and nickel impurities in mercury selenide

I.M.Tsidil’kovskii, N.K.Lerinman, L.D.Sabirzyanova, S.Yu.Paranchich, and Yu.S.Paranchich

The electron densities and mobilities were determined from measurements of the Hall effect and of the electrical conductivity. The Shubnikov-de Haas oscillations of the transverse magnetoresistance of zero-gap HgSe crystals were studied as a function of the concentrations of cobalt and nickel impurities. The experimental results indicated that the cobalt and nickel atoms formed resonant donor levels in mercury selenide.

Sov. Phys.Semicond., 1992,

v.26, № 11, pp.1062-1064.

SeNiHg xx1

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№ NNi , 1018 cm-3 m, mg

1 1 214.9

2 4 255.6

3 6 241.7

4 8 184.3

5 10 213.7

The specimens were doped by simultaneous fusion of the original

components with subsequent crystallization by the Bridgman method(lab. of prof. S.Yu.Paranchich, Chernovtsy National University, Chernovtsy, Ukraine)

Parameters of the specimens Hg1-xNixSe (5)

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SeNiHg xx1

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SQUID magnetometer (MPMS-XL-5, QUANTUM DESIGN Co.)

The experiment on the study of the temperature dependences of the magnetic susceptibility of Hg1-xNixSe were carried out at the Center of Magnetometry, Institute of Metal physics, Ural Division, Russian Academy of Sciences (Gubkin A.F.)

Experiment:

χ(T) – (1.8-300) K; B = 0.5 T___________________________________________________________________________

NNi = (1·1018-1·1019) cm-3 – 5 образцов

SeNiHg xx1

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Temperature dependence of the magnetic susceptibility of Hg1-xNixSe

nNi: 1 - 1·1018cm-3; 2 - 4·1018cm-3; 3 - 6·1018cm-3; 4 - 8·1018cm-3; 5 - 1·1019cm-3

SeNiHg xx1

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)T/(C 0

Temperature dependence of the magnetic susceptibility of Hg1-xNixSe (nNi=1·1019cm-3)

The approximation of experimental data by Curie-Weiss law.

SeNiHg xx1

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Inverse magnetic susceptibility of Hg1-xNixSe (nNi=1·1019cm-3) as a function temperature

θ ~1K for nNi = (1·1018÷1·1019)cm-3.

SeNiHg xx1

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Determining spin of nickel impurity in mercury selenide

SeNiHg xx1

)nn)(S(an)S(aC igiiigio Parameters (ν=1): Sio= 3/2, n0d=2.2 ·1018cm-3;

(ν=2): Sio= 2, n0d=0.5 ·1018cm-3;

(ν=3): Sio= 5/2, n0d=0.2·1018cm-3.

040011 ..Si

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Concentration dependence of the Curie constant of the 3d-impurities (Fe, Co, Ni) in crystals of mercury selenide

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Parameters of the localized spins of the 3d-impurities (Fe, Co, Ni)in crystals of mercury selenide

Ni2+ 3d8 donor 3 5/2 1.01±0.04 0.2

ionelectronic

configurationtype of the impurity

ν Sio Si

nod , 1018cm-3

Fe2+ 3d6 donor 1 5/2 2.1±0.1 2.6

Co2+ 3d7 donor 2 5/2 1.52±0.06 0.5

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