Jahn-teller effect and zero-phonon line isotope shifts of transition metals in II–VI compounds

Hoffmann, A.; Scherz, Udo

doi:10.1016/0022-0248(90)91002-8

Cited by 22 publications

(9 citation statements)

References 20 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…(6) is given in Refs. [23,24]. Equation (5) predicts a positive isotope shift in agreement with experiment [21,22] and makes its magnitude a measure for the coupling of the 5Τ2 excited state to a local Τ2 mode.…”

Section: Radiative and Nonradiative Transition Rates Of Ironsupporting

confidence: 73%

“…The 5Ε ground state experiences a weak coupling to E-type modes only [20], whereas for the excited The Jahn-Teller coupling in the 5Τ2 state can be evaluated on the basis of isotope shifts observed for the zero phonon absorption lines [21,22]. The mass dependence of impurity states is a consequence of mass sensitive local phonons (Τ2 modes) contributing to the total energy and the electron-phonon coupling [23]. Isotope shifts of optical transitions are a difference effect depending on both the excited Eexc and ground Egr state energy and for intracenter 3d transitions a consequence of the vibronic character of the involved states [24].…”

Section: Radiative and Nonradiative Transition Rates Of Ironmentioning

confidence: 99%

See 1 more Smart Citation

Calorimetric Absorption Spectroscopy of Deep Defects and Quantum Dots

et al. 1995

Self Cite

View full text Add to dashboard Cite

In recent years calorimetric absorption spectroscopy has been developed to a powerful tool of semiconductor spectroscopy based on the detection of nonradiative relaxation processes. Calorimetric absorption spectroscopy is an ultrasensitive quantitative absorptioii technique. Recent investigations of Fe in III-V semiconductors and of InAs/GaAs quantum dots are presented here to illustrate the potential of the method. Sharp absorption lines are observed at the low energy onset of the Fe 3 +/2 + charge transfer band in Ill-V semiconductors. Calorimetric absorption spectroscopy measurements in the mK range reveal a strong temperature dependence of their absorption strength identifying unambiguously Fe3+ ( 6 Α1 (S)) as a ground state. The excited state is attributed to (Fe2+ ,h). The importance of exchange interactioii for the observed fine structure is pointed out and binding energies are determined. The quantum yield of the intracenter 5 Τ2 -5E transition of Fee+ is determined to be below 50% at 2 K. Α correlatioii between the nonradiative relaxation rate and the isotope splitting of the 5Τ2-5E transition is observed, demonstrating the crucial role of the dynamical Jahn-Teller coupling of the 5 Τ2 state to local T2 modes for the multiphonon relaxation process. Quantum dots having a d-function density of states should exhibit no Stokes shift between absorption and emission as observed for one-and two-dimensional systems. Calorimetric absorptioii spectroscopy demonstrates ground state absorption coinciding in energy with the luminescence for self-organized InAs/GaAs quantum dot structures grown by MBE. Transitions into excited hole states are resolved and a comparison to photoluminescence excitation spectroscopy is presented.

show abstract

Section: Radiative and Nonradiative Transition Rates Of Ironsupporting

confidence: 73%

Section: Radiative and Nonradiative Transition Rates Of Ironmentioning

confidence: 99%

Calorimetric Absorption Spectroscopy of Deep Defects and Quantum Dots

et al. 1995

Self Cite

View full text Add to dashboard Cite

show abstract

“…Such shifts have been reported for instance for C complexes produced in silicon by electron irradiation, 1 but also in the spectra of different substitutional transition metals in compound semiconductors. 2,3 In silicon, substitutional chalcogen atoms ͑S, Se, and Te͒ have two more valence electrons than Si. The binding energy of the first electron is rather large ͑ϳ0.3 eV for S and Se͒ compared to that for group V donors P and As in silicon ͑ϳ0.05 eV͒, but within shifts of their positions, the electronic line spectra of S 0 , Se 0 , P, and As donors are strikingly similar as they involve effective-mass-like excited states.…”

Section: Introductionmentioning

confidence: 99%

Isotope effects in the electronic spectrum ofS+andSe+in silicon

Pajot¹,

Clerjaud

McCluskey

2004

Phys. Rev. B

View full text Add to dashboard Cite

Weak satellites of the strong and sharp parity-forbidden, but symmetry-allowed 1s(A 1 )→1s(T 2 ) doublet of the S ϩ donor spectrum in silicon are reported. The low-energy ones are ascribed to a Si isotope effect and the high-energy ones to an S isotope effect. We also show that the profile of the low-energy component of the same transition of Se ϩ in silicon can be reproduced from the computed combination of Si and Se isotope shifts with the same characteristics as those of S ϩ , but with a smaller Se isotope shift. The Si isotope shift is discussed in terms of the bond softening effect in the electronic ground state for a cluster involving the chalcogen atom and its first nearest neighbors. The positive chalcogen isotope shift is discussed by considering the effect of a vibronic coupling to the 2 mode of vibration in the excited state within the bond softening framework. It is also shown that this vibronic coupling can account for the noneffective mass behavior of the 1s(T 2 ) level.

show abstract

“…The LVM of transition metal ions of the iron group substituting for the cations at random sites in II-VI semiconductors having the zinc-blende structure have also been observed by Mayur et al [15] in infrared absorption with as many lines as there are isotopes of the impurity and with intensities proportional to their natural abundances. Among other such investigations, we also mention the observation of isotope-dependent LVM's of Ni and Cu in CdS and ZnS [16,17].…”

Section: Introductionmentioning

confidence: 95%

Isotope splitting of the zero-phonon line of Fe2+ in cubic III–V semiconductors

Colignon

Mailleux

Kartheuser

et al. 1998

Solid State Communications

View full text Add to dashboard Cite

A theoretical study of the isotopic-mass dependence of the internal transitions of Fe 2+ at a cation site in a cubic zinc-blende semiconductor is presented. The model used is based on crystal-field theory and includes the spinorbit interaction and a weak dynamic Jahn-Teller coupling between the 5 Γ 5 excited manifold of Fe 2+ and a local vibrational mode (LVM) of Γ 5 symmetry. The mass dependence of the LVM frequency is described, in the harmonic approximation, within two different limits: the rigid-cage model and a molecular model. In the rigidcage model, the Fe 2+ ion undergoes a displacement but the rest of the lattice is fixed. In this case, a simple M -1l2 dependence of the frequency is obtained and the Jahn-Teller energy, E JT is independent of the mass. In the molecular model, the four nearest neighbors of the magnetic ion are allowed to move and the LVM then behaves as the Γ 5 mode of a MX 4 tetrahedral molecule leading to a more complicated dependence of the frequency on the isotopic mass and to a mass-dependence of E JT . The theoretical results obtained with these two models are compared with the observed isotopic shifts of the zero-phonon lines in InP:Fe and GaP:Fe corresponding to an optical transition between the vibronic Γ 1 ground state and the lowest Γ 5 state originating from the 5 Γ 5 excited orbital multiplet. A prediction of the isotopic shifts of the zero-phonon line in GaAs:Fe is also presented.

show abstract

Jahn-teller effect and zero-phonon line isotope shifts of transition metals in II–VI compounds

Cited by 22 publications

References 20 publications

Calorimetric Absorption Spectroscopy of Deep Defects and Quantum Dots

Calorimetric Absorption Spectroscopy of Deep Defects and Quantum Dots

Isotope effects in the electronic spectrum ofS+andSe+in silicon

Isotope splitting of the zero-phonon line of Fe2+ in cubic III–V semiconductors

Contact Info

Product

Resources

About