Quality of Bulk Cdte Substrates and Its Relation to Intrinsic Defects

ABSTRACTBoth the cadmium vacancy (Vcd) and the tellurium vacancy (VTe) in CdTe are identified by means of electron paramagnetic resonance (EPR). The VCd is a double acceptor and the EPR spectrum is observed in its single negative charge state. The symmetry is found to be trigonal, which can be explained in a model in which the hole occupies a dangling bond t2 orbital and the orbital degeneracy is removed by a static Jahn-Teller distortion. The hyperfine interaction shows that the hole is localised on one of the four Te neighbours. The EPR spectrum of VTe+ reveals cubic (unperturbed) symmetry and the hyperfine structure shows that the unpaired electron is equally spread over the four Cd neighbours.Photo-EPR measurements locate the 0/+ state of VTe at Ev + 0.2 eV and the 2−/− acceptor level of VCd to be situated less than 0.47 eV above the valence band.

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Quality of Bulk CdTe Substrates and its Relation to Intrinsic Defects

MRS Proceedings ◽

10.1557/proc-299-185 ◽

1994 ◽

Vol 299 ◽

Author(s):

B. K. Meyer ◽

D. M. Hofmann ◽

W. Stadler ◽

P. Emanuelsson ◽

P. Omling ◽

...

Keyword(s):

Negative Charge ◽

Acceptor Level ◽

Dangling Bond ◽

Epr Spectrum ◽

Paramagnetic Resonance ◽

Teller Distortion ◽

Jahn Teller ◽

Electron Paramagnetic ◽

Jahn Teller Distortion

AbstractBoth the cadmium vacancy (Vcd) and the tellurium vacancy (VTe) in CdTe are identified by means of electron paramagnetic resonance (EPR). The Vcd is a double acceptor and the EPR spectrum is observed in its single negative charge state. The symmetry is found to be trigonal, which can be explained in a model in which the hole occupies a dangling bond t2 orbital and the orbital degeneracy is removed by a static Jahn-Teller distortion. The hyperfine interaction shows that the hole is localised on one of the four Te neighbours. The EPR spectrum of VTe+ reveals cubic (unperturbed) symmetry and the hyperfine structure shows that the unpaired electron is equally spread over the four Cd neighboursPhoto-EPR measurements locate the 0/+ state of VTe at Ev + 0.2 eV and the 2-/- acceptor level of VCd to be situated less than 0.47 eV above the valence band.

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Electron paramagnetic resonance studies of Cu 2+ ions in KZnClSO 4 ·3H 2 O: an observation of Jahn–Teller distortion

Journal of Physics and Chemistry of Solids ◽

10.1016/s0022-3697(99)00420-5 ◽

2000 ◽

Vol 61 (8) ◽

pp. 1209-1215 ◽

Cited By ~ 39

Author(s):

K.V. Narasimhulu ◽

C.S. Sunandana ◽

J.L. Rao

Keyword(s):

Electron Paramagnetic Resonance ◽

Paramagnetic Resonance ◽

Teller Distortion ◽

Jahn Teller ◽

Electron Paramagnetic ◽

Jahn Teller Distortion

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Jahn-Teller Distortion in Dangling-Bond Linear Chains Fabricated on a Hydrogen-Terminated Si(100)-2×1Surface

Physical Review Letters ◽

10.1103/physrevlett.82.4034 ◽

1999 ◽

Vol 82 (20) ◽

pp. 4034-4037 ◽

Cited By ~ 86

Author(s):

Taro Hitosugi ◽

S. Heike ◽

T. Onogi ◽

T. Hashizume ◽

S. Watanabe ◽

...

Keyword(s):

Dangling Bond ◽

Teller Distortion ◽

Linear Chains ◽

Jahn Teller ◽

Jahn Teller Distortion

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Ab initioEPR parameters for dangling-bond defect complexes in silicon: Effect of Jahn-Teller distortion

Physical Review B ◽

10.1103/physrevb.85.195202 ◽

2012 ◽

Vol 85 (19) ◽

Cited By ~ 11

Author(s):

Gernot Pfanner ◽

Christoph Freysoldt ◽

Jörg Neugebauer ◽

Uwe Gerstmann

Keyword(s):

Dangling Bond ◽

Teller Distortion ◽

Defect Complexes ◽

Jahn Teller ◽

Jahn Teller Distortion

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Modifying Jahn-Teller distortion by epitaxial stress in LaMnO3 films for tunning electron localization

Journal of Physics Condensed Matter ◽

10.1088/1361-648x/ac3f02 ◽

2021 ◽

Author(s):

Xin Chen ◽

Baohua Wang ◽

Tongxin Ge ◽

Haoming Wei ◽

Bingqiang Cao

Keyword(s):

Transport Properties ◽

Electrical Transport ◽

Reciprocal Space ◽

Electron Localization ◽

Electrical Transport Properties ◽

High Quality ◽

Teller Distortion ◽

Jahn Teller ◽

Jahn Teller Distortion

Abstract The effect of epitaxial stress on Jahn-Teller distortion in epitaxial LaMnO3 (LMO) films has been investigated. Both 2θ-ω scans and reciprocal space maps indicate that LMO samples are subjected to compressive stress. Obvious Laue oscillations can be detected in 2θ-ω scans, indicating the high quality of samples. Reciprocal space maps of symmetry peak (001) and asymmetry peak (-103) imply different epitaxial stress for LMO films deposited on different substrates. Raman spectra measurements reveal that the degree of Jahn-Teller distortion can be well tuned via the epitaxial stress which may further influence on the electron localization in the films. This study might benefit to understanding the correlation between crystalline structure and electrical transport properties of LMO films and related LMO-based superlattices.

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Structure-Property Relations in xCuO-(1-x)As2O3-0.7B2O3 (0.01≤x≤0.05) Glasses by Magnetic Susceptibility Measurements, IR and EPR Spectroscopy

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.111.103 ◽

2006 ◽

Vol 111 ◽

pp. 103-106

Author(s):

B.B. Das ◽

A. Gopinath

Keyword(s):

Magnetic Susceptibility ◽

Structure Property ◽

X Ray Diffraction ◽

Paramagnetic Resonance ◽

Teller Distortion ◽

Property Relations ◽

Structure Sensitive ◽

Jahn Teller ◽

Linear Fit ◽

Jahn Teller Distortion

Studies on xCuO-(1-x)As2O3-0.7B2O3(0.01≤x≤0.05) (G1-G5: x = 0.01, 0.02, 0.03, 0.04, 0.05) glasses were done using varieties of structure sensitive techniques. The powder X-ray diffraction (XRD) studies show the formation of glasses in the composition. The IR spectral results show the presence of Cu-O bond, planar [BO3/2] and [BO3 -n](n=1, 2, 3) units and tetrahedral {BO4/2]- units. The magnetic susceptibility results show Curie-Weiss behaviour in the range 4.2-400 K. The calculated values of the exchange integral from the Weiss constant obtained form the linear fit of the Curie-Weiss law are found to be in the range 5.22-29.50 meV. From the trend of the gmatrices of gơ>g⊥>ge (ge =2.0023) obtained from electron paramagnetic resonance (EPR) lineshapes simulation we conclude that the paramagnetic site in these glasses is Cu2+(3d9) which is in a tetragonally elongated octahedron [O1/2-CuO4/2-O1/2] exhibiting Jahn-Teller distortion having D4h symmetry with orbital singlet 3dx2-y2 (2B1g) as the ground state.

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EPR Study of the Dynamic Jahn-Teller Effect of Cu2+ in CdBa(HCOO)4 · 2H2O Single Crystals

Zeitschrift für Naturforschung A ◽

10.1515/zna-1998-1203 ◽

1998 ◽

Vol 53 (12) ◽

pp. 945-950 ◽

Cited By ~ 1

Author(s):

Hüseyin Kalkan ◽

Sehriman Atalay ◽

Ismet Senel

Keyword(s):

Teller Effect ◽

Spin Hamiltonian ◽

Temperature Dependent ◽

Angular Variation ◽

Powder Spectrum ◽

Epr Spectrum ◽

Paramagnetic Resonance ◽

Jahn Teller ◽

Jahn Teller Effect ◽

Electron Paramagnetic

Abstract Electron Paramagnetic Resonance spectra of Cu2+ doped into cadmium barium formate dihydrate single crystal were studied at 300 K. The powder spectrum of this material was studied at 300 to 133 K. The values of the g and A hyperfine tensors were found to be temperature dependent. The temperature dependence of the Cu2+ EPR spectrum is discussed in terms of the dynamic Jahn-Teller effect. The angular variation of the spectra indicates the substitution of the host Cd2+ with Cu2+ . The spectra were fitted with a tetragonal spin-Hamiltonian, the parameters of which were determined at 300 K. The ground-state wave function of the copper complex has been constructed at 113 K and 300 K.

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Orbital Order and Spin Relaxation in La0.95Sr0.05MnO3

Modern Physics Letters B ◽

10.1142/s0217984903005494 ◽

2003 ◽

Vol 17 (10n12) ◽

pp. 469-477

Author(s):

B. I. Kochelaev ◽

E. Shilova ◽

J. Deisenhofer ◽

H.-A. Krug von Nidda ◽

A. Loidl ◽

...

Keyword(s):

Crystal Field ◽

Angular Dependence ◽

Spin Relaxation ◽

Critical Behavior ◽

Orbital Order ◽

Paramagnetic Resonance ◽

Teller Distortion ◽

Teller Transition ◽

Jahn Teller ◽

Jahn Teller Distortion

We analyze the temperature and angular dependence of the paramagnetic-resonance linewidth of La 0.95 Sr 0.05 MnO 3. The observed anisotropy can be well described by the crystal field contributions originated by the Jahn–Teller distortion. The critical behavior of the linewidth at the Jahn–Teller transition is found to be directly related with the orbital order.

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Electron Paramagnetic Resonance Studies of Nb in 6H-SiC

Materials Science Forum ◽

10.4028/www.scientific.net/msf.740-742.385 ◽

2013 ◽

Vol 740-742 ◽

pp. 385-388

Author(s):

Xuan Thang Trinh ◽

Andreas Gällström ◽

Nguyen Tien Son ◽

Stefano Leone ◽

Olle Kordina ◽

...

Keyword(s):

Electron Paramagnetic Resonance ◽

Charge State ◽

Negative Charge ◽

Chemical Vapor ◽

Epr Spectrum ◽

Paramagnetic Resonance ◽

Hamiltonian Parameters ◽

Electron Paramagnetic ◽

Epr Experiments ◽

Neutral Charge State

Defects in unintentionally Nb-doped 6H-SiC grown by high-temperature chemical vapor deposition were studied by electron paramagnetic resonance (EPR). An EPR spectrum with a hyperfine (hf) structure consisting of ten equal-intensity lines was observed. The hf structure is identified to be due to the hf interaction between an electron spin S=1/2 and a nuclear spin of 93Nb. The hf interaction due to the interaction three nearest Si neighbors was also observed, suggesting the involvement of the C vacancy (VC) in the defect. Only one EPR spectrum was observed in 6H-SiC polytype. The obtained spin-Hamiltonian parameters are similar to that of the Nb-related EPR defect in 4H-SiC, suggesting that the EPR center in 6H-SiC is the NbSiVC complex in the neutral charge state, NbSiVC0. Photoexcitation EPR experiments suggest that the single negative charge state of the NbSiVC complex is located at ~1.3 eV below the conduction band minimum.

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The Interplay of Open-Shell Spin-Coupling and Jahn-Teller Distortion in Benzene Radical Cation Probed by X-ray Spectroscopy

10.26434/chemrxiv.12799922.v2 ◽

2020 ◽

Author(s):

Marta L. Vidal ◽

Michael Epshtein ◽

Valeriu Scutelnic ◽

Zheyue Yang ◽

Tian Xue ◽

...

Keyword(s):

High Harmonic ◽

Open Shell ◽

Spin Coupling ◽

High Symmetry ◽

Teller Distortion ◽

Spectral Window ◽

X Ray ◽

Jahn Teller ◽

X Ray Absorption ◽

Jahn Teller Distortion

We report a theoretical investigation and elucidation of the x-ray absorption spectra of neutral benzene and of the benzene cation. The generation of the cation by multiphoton ultraviolet (UV) ionization as well as the measurement of the carbon K-edge spectra of both species using a table-top high-harmonic generation (HHG) source are described in the companion experimental paper [M. Epshtein et al., J. Phys. Chem. A., submitted. Available on ChemRxiv]. We show that the 1sC -> pi transition serves as a sensitive signature of the transient cation formation, as it occurs outside of the spectral window of the parent neutral species. Moreover, the presence of the unpaired (spectator) electron in the pi-subshell of the cation and the high symmetry of the system result in significant differences relative to neutral benzene in the spectral features associated with the 1sC ->pi* transitions. High-level calculations using equation-of-motion coupled-cluster theory provide the interpretation of the experimental spectra and insight into the electronic structure of benzene and its cation. The prominent split structure of the 1sC -> pi* band of the cation is attributed to the interplay between the coupling of the core -> pi* excitation with the unpaired electron in the pi-subshell and the Jahn-Teller distortion. The calculations attribute most of the splitting (~1-1.2 eV) to the spin coupling, which is visible already at the Franck-Condon structure, and estimate the additional splitting due to structural relaxation to be around ~0.1-0.2 eV. These results suggest that x-ray absorption with increased resolution might be able to disentangle electronic and structural aspects of the Jahn-Teller effect in benzene cation.

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