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We present photoluminescence and modal gain measurements in a Ga(NAsP) single-quantum well sample pseudomorphically grown on silicon substrate. The temperature dependence indicates that disorder induced localization effects dominate the low temperature photoluminescence spectra. Nevertheless, using the variable stripe length method, we observe modal gain values up to 15 cm-1at room temperature. These values are very promising, demonstrate the high optical quality of the new dilute nitride material Ga(NAsP) and underline its candidacy for electrically pumped lasers on silicon substrate.

We present an overview of the quantum design, growth and lasing operation of both IR and mid-IR OPSL structures aimed at extracting multi-Watt powers CW and multi-kW peak power pulsed. Issues related to power scaling are identified and discussed. The IR OPSLs based on InGaAs QW bottom emitters targeted at wavelengths between 1015nm and 1040nm are operated in CW mode (yielding a maximum power of 64W) and pulsed (peak power of 245W). The mid-IR top emitter OPSLs designed to lase at 2m are based on a novel lattice mismatched growth using InGaSb QWs and yield a maximum peak power of 350W pulsed.

The post-growth annealing behaviour of Ga(NAsP) multi quantum well heterostructures (MQWHs) grown pseudomorphically strained to GaP substrate has been investigated. The optical properties as well as the structural crystal quality of the novel dilute nitride show an obvious dependence on the applied annealing temperature. Photoluminescence (PL) measurements reveal a step-like blue shift of the PL peak position in line with an increase of PL intensity with rising annealing temperature. The PL line width decreases to a mini- mal value for an optimized heating temperature around 800 °C. This annealing behaviour of the Ga(NAsP)/GaP-MQWHs up to 850 °C is quite typical for a dilute nitride, however, the functional dependence of the integrated intensity above 850 °C is unusual. The increase of the PL line width above 850 °C suggests a deterioration of the crystalline MQW quality, but transmission electron microscopy (TEM) and high resolution X-ray diffraction (XRD) prove the opposite. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

The puzzling electronic properties of GaAsN have been investigated through the compositional dependence of two highly sensitive band structure parameters: the electron effective mass, me, and the electron gyromagnetic factor, ge. In the N concentration range from 0% to 0.7%, both me and ge show a highly nonlinear dependence on N composition that can be explained in terms of alternating on- and off-resonance conditions between the red-shifting conduction band edge and specific energy-pinned N cluster states. Furthermore, the electronic properties of the material are studied under hydrostatic pressure, P. This allows tuning in a same sample the interaction between extended and localized states and disclosing a hierarchy between different nitrogen complexes as regards the extent of the perturbation these complexes exert on the electronic properties of the GaAs host crystal. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Abstract: The magneto-transport properties of granular paramagnetic–ferromagnetic GaAs:Mn/MnAs hybrids have been studied. Positive and negative magnetoresistivity can be observed in the paramagnetic matrix as well as in the GaAs:Mn/MnAs hybrid system. The experimental results and the respective relevant interactions are discussed. A phenomenological explanation from a microscopic point of view is presented. It is suggested that the paramagnetism of the matrix plays a major role in the magneto-resistive behavior of the hybrids, in contrast to diamagnetic–ferromagnetic hybrids where the magnetoresistance (MR) is dominated by the ferromagnetism of the clusters.

In recent years, numerous computer assisted learning (CAL) programmes based on new teaching methods, as for example the principles of cognitive apprenticeship and problem based learning, have euphorically been developed for various medical fields. However, many of these programmes failed due to either low acceptance, economic inefficiency, or, most seriously, problems with the implementation and evaluation in medical curricula. In 1999, the practical training course 'Dermatology 2000', an interactive multimedia programme for dermatological education, was developed and completely integrated into the regular dermatological curriculum of five German medical schools. The formative evaluation of an implemented relational database revealed contemporary information about the programme's quantity of use. So far, 3050 students have participated in 6557 lessons. The evaluation of two online questionnaires showed a high learner acceptance regarding the programme's instructional design, ergonomics, and didactical presentation and, after completion of Dermatology 2000, an increased interest in medical education software. A comparison of the objective learning outcome illustrated that Dermatology 2000 students (n = 31) not only outperformed non-participants (n = 7) but also showed a (10%) lower rate of errors in a conventional knowledge test. Additionally, single-case studies demonstrated the increased ability of participating students to apply the acquired knowledge to diagnostic problems. We conclude that the implementation of CAL in present medical curricula can contribute to reformations of medical education. The instructional design of Dermatology 2000 is well accepted and suitable to provide both theoretic biomedical knowledge and clinical skills.

It is well established that the ferromagnetism of (Ga,Mn)As is mediated by holes. An important parameter in this context is the p–d exchange integral N0β as the RKKY interaction parameter JRKKYis proportional to (N0β)2. In magnetic semiconductors, magnitude and sign of N0β are strongly dependent on the local electronic configuration of the Mn-ion and on the free carrier density. To investigate the correlation between the p–d exchange interaction and doping in Ga1−xMnxAs, paramagnetic samples with x≈0.1% have been intentionally n-doped with Te. High-field Hall measurements at 1.6 K confirm that with increasing degree of Te co-doping, the samples change from p- to n-type. The magnetic field induced splitting of the excitonic and electronic states has been studied by various magneto-optical spectroscopic techniques at 1.8 K and external magnetic fields up to 7.5 T. The p–d exchange integral changes from N0β > 0 (ferromagnetic coupling) to N0β < 0 (antiferromagnetic coupling) with increasing degree of Te co-doping. Thus, N0β can be tuned and can even change its sign in dependence on the doping conditions of the Mn-containing layers.

We studied the correlation between magnetoresistance (MR) effects and the type of conducti- vity in paramagnetic Ga1−xMnxAs with x< 0.5%. Series of samples of (Ga,Mn)As with different codoping levels of Te have been prepared by metal-organic vapor-phase epitaxy (MOVPE). With increasing Mn-content from doping levels to x= 0.5% in paramagnetic Ga1−xMnxAs, the MR at 1.6 K changes continuously from positive to strongly negative. This manifests the complex interplay between p–d exchange induced valence band splitting and the metal–insulator transition. Codoping with Te leads eventually to a dominant conduction band transport. It is characterized by a small negative contribution at low magnetic fields to the parabolic MR similar to that found in highly n-doped diamagnetic semiconductors. It shows that the Mn-induced conduction band splitting is much smaller than the valence band splitting, i.e., |N0α| ≪ |N0β|.

We have investigated the optical properties of edge-emitting laser structures containing three Ga0.7In0.3N0.005As0.995 quantum wells embedded in GaNxAs1–x barriers grown by metal-organic vapour-phase epitaxy. In a series of three samples the nitrogen content x of the barrier was varied from 0% to 3%. We studied the optical transitionsand the threshold of these laser structures by using pressure-dependent photomodulated reflectance (PR) up to 20 kbar at room temperature. Additionally we measured the pressure dependence of the lasing energy and the threshold current of the corresponding laser structures as function of hydrostatic pressure. Due to the large red-shift of the Ga(N,As) band gap with increasing N of about 150 meV per percent N, the variation of x leads to a considerable change of the carrier confinementof holes and, in particularly, of electrons. The strong increase of the threshold current of the laser device with pressure suggests a swiftly increasing threshold carrier density due to the increasing effective mass and non-parabolicity.an enlarged carrier density at threshold Comparing the pressure dependence of the lasing energy and the conduction band edge furthersupports this conclusion.

The influence of coupling, correlation, and disorder on exciton and biexciton signatures is investigated using coherent excitation spectroscopy. Different biexciton-induced transitions of a single biexciton state are spectrally resolved. One of the transitions is found to be particularly sensitive to disorder. Mixed biexciton resonances, resulting from attractively interacting heavy and light hole exciton states, are identified. The observations are analyzed on the basis of microscopic model calculations.

We investigate the impact of waveguide properties on the performance of surface-emitting second-harmonic generation (SESHG) devices. Using multi-layer AlGaAs/GaAs ridge waveguides that are optimized for SESHG at fundamental wavelengths λω= 1060 and 1550 nm, we achieve nonlinear cross-sections among the highest reported so far. In these devices, characteristics of the guided fundamental wave strongly determine the SESHG performance: multiple reflections in the longitudinal direction affect the conversion efficiency while higher order lateral waveguide modes modify the SESHG farfield. Both effects are significant for applications of SESHG in integrated photonic circuits.

A series of GaN x As 1 m x /GaAs quantum well structures with well widths of about 20 nm and x varying between 1% and 3.5% has been grown by metal-organic vapour phase epitaxy. We have studied the evolution of the quantum well states under hydrostatic pressure up to 20 kbar at 300 K by photomodulated reflectance (PR) spectroscopy. The energy positions of the quantum well transitions have been obtained by fitting the PR spectra. The pressure dependence of the allowed heavy-hole transitions e n hh n decreases with increasing n . This directly reflects the strong non-parabolic dispersion of the conduction band originating from the interaction of the N-impurity level with the bands of the GaAs host. The fitted energy positions and their pressure dependence can be well described by a 10 band k.p model. The observed splitting between the lowest light-hole and heavy-hole transitions are in agreement with a type I band alignment.

We report photo‐modulated reflectance studies under applied pressure and variable temperature, and related calculations, that probe the influence of N‐related resonant anti‐bonding states on the electronic structure of dilute III–N–V quantum wells (QWs). Three InyGa1—yAs1—xNx/GaAs multiple QW samples with N contents of 0–2.5% are investigated up to 85 kbar at 300 K, and for 300–10 K at 1 atm. While the temperature dependence is only minimally affected by the N content, the pressure shifts of the intersubband transition energies depend significantly on the percentage of N. The linear pressure coefficients are much smaller than those of the InGaAs band gap. A ten‐band k · pmodel is in broad accord with the observed pressure dependence; the predicted non‐linear shift is somewhat larger than measured.

The pressure and temperature dependence of quantum well transitions in GaNxAs1—x/GaAs quantum well structures with xN= 1.8% and various well widths grown by metal organic vapour phase epitaxy were studied by photomodulated reflectance (PR) spectroscopy. The quantum well transition energies and their pressure dependence can be well described by a ten‐band k · pHamiltonian. Comparing experiment and theory demonstrates that the band alignment of the quantum well structures is type I with a chemical valence band offset of about 30% ± 5% for xN= 1.8%. The temperature coefficients of the quantum well states are to a good approximation independent of well width and considerably smaller than that of GaAs.

GaNxAs1-x samples with × ranging from 0.043% to 2.8% were grown by MOVPE. Analysing low-temperature photoluminescence spectra taken under hydrostatic pressure and room temperature photomodulated reflectance spectra gives strong evidence that the transition from N acting as an isoelectronic impurity to forming N-induced bands takes place at a N-concentration of about 0.2%.

We show that interaction-assisted modes of transport play a role in the energy relaxation of excitons in disordered GaAs quantum wells. Semitransparent gold films are found to induce a blue shift in the photoluminescence spectrum of disordered wells. We interpret the result in terms of a long-range electromagnetic hopping coupling suppressed by image dipoles in the gold. The results are supported by Monte Carlo simulations of electromagnetically-assisted exciton hopping using hop rates modified by the gold layer.

We study the decay of an optically excited cloud of carriers as a function of its initial diameter d. Values as low as d = 100 nm are possible via metallic apertures on bulk GaAs fabricated by electron beam lithography. We find that the decay time τ versus d scales as τ ∝ d2 for large d, as expected for diffusive transport, and as τ ∝ d for submicron values of d, indicating strong deviations from diffusive transport. The dependence on parameters such as initial carrier kinetic energy, carrier density and sample temperature is discussed.

We study semiconductor quantum-well samples with different disorder strengths by coherent excitation spectroscopy with particular emphasis on disorder-mediated couplings of exciton subensembles. Our experiments show that there is no coherent coupling of excitons in different quantum islands and in a strongly inhomogeneously broadened sample. Latest results with polarization-resolved coherent excitation spectroscopy indicate a disorder-induced dephasing of biexcitons in the inhomogeneously broadened sample.

Quantum wells of the quaternary (GaIn)(NAs) alloy are grown compressively strained on GaAs by metal‐organic vapor phase epitaxy (MOVPE) at low temperatures under non‐equilibrium conditions. Growth experiments of particular heteroepitaxial multilayer systems are reported and the influence of varying conditions, namely of the arsenic source partial pressure and of the growth rate on the structural quality of the quantum wells is studied. Up to a critical amount of incorporated nitrogen, high perfection layers can be obtained which show a roughness of the interfaces between the wells and the barriers in the range of only a few monolayers. Any phase separation effects have been excluded by exact control of the particular growth conditions. For the structural characterization of the layer systems, conventional and high resolution transmission electron microscopy have been applied.

Four-junction photovoltaic solar cells are expected to reach conversion efficiencies around 40%. Mechanical stacking of two monolithic tandem cells is suggested. As a top cell the highly developed (GaIn)P/GaAs tandem cell is considered. Device modelling is presented for the bottom cell. An infrared monolithic tandem solar cell is proposed which is a combination of an (AlGa)(AsSb) top cell (Egap=1.03 4;eV) and a GaSb bottom cell based on GaSb as substrate material. The MOVPE growth of GaSb, Ga(AsSb) and (AlGa)Sb in a multiwafer planetary reactor that is suited to large-scale industrial production is reported. Influences of the substrate preparation, orientation of the growth surface, growth temperature and the V–III ratio on material quality are presented. Both hydrogen and nitrogen were employed as the carrier gas in different experiments. The best layers were obtained on (100) substrates oriented 2° toward (111)A, using hydrogen as carrier.

For the first time, a successful growth of Ga1−xMnxAs layers on (100)GaAs substrates by metal-organic vapour-phase epitaxy is reported. Optical and magneto-optical spectroscopy of the E0, E1and E1+Δ1transitions is possible due to the high structural quality of the samples. A strong exchange interaction is found in the Ga1−xMnxAs layers between the magnetic moments of manganese and the excitonic states, which exhibits an effective ferromagnetic coupling. The Mn concentrations in the layers can be estimated by two different and independent optical methods (i) from the Zeeman splitting of the E0excitons and (ii) from the red-shift of the E1transition due to the p-doping with Mn.

First, we study coupling of excitons in different quantum-well islands by coherent excitation spectroscopy and find that excitons in different islands are not coherently coupled. Second, we investigate exciton and biexciton binding energies in inhomogeneously broadened (GaIn)As/Ga(PAs) multi quantum wells. A strong increase of the 1s–2s-splitting with increasing exciton localization is found, whereas the biexciton binding energy shows a very weak decrease with increasing localization.

Background: For cost-utility-analyses in pharmaco-economic research, it is necessary to additionally assess quality-of-life (QoL) parameters for content validation of the utilities. Utilities such as ‘willingness-to-pay’ and ‘time-trade-off’ bear several advantages in comparison to questionnaires of QoL: utilities are more practicable and provide data that are easier to use for pharmaco-economic evaluations.Objective: Development of suitable questions for assessing both ‘willingness-to-pay’ and ‘time-trade-off’ and evaluation of correlation with a standardized QoL questionnaire.Methods: Both assessments were employed in a survey on patients suffering from psoriasis vulgaris pre and post treatment with synchronous balneo-phototherapy. Simultaneously the Psoriasis Disability Index (PDI) for evaluation of quality-of-life was used.Results: Data of 105 patients could be annualized. Com-pared to the assessments pre treatment, mean reduction of PDI was 25.5% (29 pre treatment, 21.6 post treatment), mean reduction in willingness-to-pay was 22.5% (proportion of monthly income in %: 16 pre to 12.4 post treatment) and mean reduction in time-trade-off 1% (percentage of hours per day: 3.4 pre to 3.3 post treatment). While willing-ness- to-pay is highly correlated with the PDI (p < 0.05), time-trade- off does not seem to be a valid parameter for assessment of utilities over time in this target population.Conclusion: The results indicate that the principle of willingness- to-pay bears high potential for use in dermatological indications, especially in pharmaco-economic evaluations.

Abstract: (GaIn)(NAs)/GaAs multiple quantum well (MQW) structures with high structural perfection as determined from high-resolution x-ray diffraction (XRD) analysis have been deposited by low-temperature metal organic vapor phase epitaxy (MOVPE) at 525C using triethylgallium (TEGa) and trimethylindium (TMIn) in combination with 1,1-dimethylhydrazine (UDMHy) and tertiarybutylarsine (TBAs). The optical characteristics of as-grown MQW structures as a function of quaternary composition and of well width are established by PL spectroscopy at 300 K. With increasing N-content a reduction in PL efficiency and an increase in PL linewidth is observed. This behavior might be correlated to an increase in defect density with increasing N-content and/or to a bandstructure effect in this novel material system. For an increase in Inconcentration the tendency for a reduction in the extreme bowing of the band gap is detected. Strong quantization effects are observed for well widths below 5 nm only in this novel MQW system, which indicates significantly larger electron masses as compared to N-free (GaIn)As.

Abstract Variations in the length of simple repetitive tandem repeats (microsatellite instability, MIN) between constitutive and tumour DNA, which is characteristic of tumours in patients affected with hereditary nonpolyposis colon cancer (HNPCC), have been found to be very important in the carcinogenesis of a variety of human neoplasms. Recently, MIN has been found in sebaceous and colorectal tumours as well as in keratoacanthomas of Muir-Torre syndrome. In order to elucidate the significance of both MIN and loss of heterozygosity (LOH) in the pathogenesis of sporadic keratoacanthomas, the presence of MIN and LOH at five loci [chromosome 5q21 (D5S346, APC), 9p21 (D9S171, p16), 10pter (D10S89, Mfd28), 11p (D11S904) and 17p12 (D17S520, p53)] was evaluated. MIN was found at only one locus (p53) in 1 of 12 keratoacanthomas and no evidence for the presence of LOH could be detected. Our results suggest that, in contrast to keratoacanthomas associated with Muir-Torre syndrome, neither MIN nor LOH appear to be significant in the induction of sporadic keratoacanthomas.:

Abstract During successive cell divisions of mortal cells the length of the telomeres (TTAGGG repeats in vertebrates) at the end of chromosomes decreases. It has been suggested that this process is responsible for cellular senescence. Expression of the ribonucleoprotein telomerase appears to prevent shortening of telomeres in germ-line cells and cancer cells. The purpose of this study was to investigate telomerase activity in melanocytic lesions and its possible role in the multistep tumor progression model of malignant melanoma. To quantify the level of telomerase activity both in cultured cells and in fresh tissue samples the TRAP (telomeric repeat amplification protocol) ELISA was used. Eight cell lines of malignant melanoma, 3 primary cultures of fibroblasts, 36 melanocytic naevi, 5 atypical melanocytic naevi, 3 Spitz’s naevi, 31 primary malignant melanomas and 13 metastases of malignant melanomas were investigated. Also 34 samples of skin (22 samples of perilesional skin and 12 samples of normal skin) were analysed. In our experiments all melanoma cell lines were strongly positive, whereas in fibroblasts telomerase activity could not be detected. Of the primary melanomas and metastatic melanomas, 90.3% and 92.3%, respectively, were strongly positive, and of the atypical melanocytic naevi, 80% were positive. Of the 36 common melanocytic naevi only 10 (27.7%) expressed weak telomerase activity and of the 34 samples of human skin, 4 (11.7%) expressed very weak telomerase activity. Our results indicate that telomerase activity increases from benign melanocytic naevi to atypical naevi and further to malignant melanoma and metastatic melanoma cells, and therefore may play a role in tumour initiation and progression.:

We have investigated the unusual band formation at the Γ-point and in the vicinity of the L-point in the alloy system Ga(N,As) by various spectroscopic methods. A series of GaNxAs1—x epitaxial layers with x varying from 0.05 to 2.8% was grown on (100) GaAs by metal-organic vapour phase epitaxy. The samples were studied by photoluminescence (PL) as well as photoluminescence excitation (PLE) spectroscopy, photomodulated reflectance (PR), and conventional reflectance (R) spectroscopy at room temperature and liquid helium temperature. The low-temperature PL and PLE spectra in the spectral region of the E0 band gap show clear evidence for in-gap nitrogen-pair and cluster states at low concentrations (x < 0.1%), and for higher nitrogen concentrations the formation of a new band. The dependence of the E0 band gap on N-content for x < 1% at 8 K is considerably stronger than at 300 K. Furthermore, R spectra of the E1 and E1 + Δ1 transitions show an uncommonly strong disorder-induced broadening with increasing N-content.

Abstract:  Natural minerals, such as widespread quartz and feldspars, have physical properties which enable them to be used as radiation dosimeters. The underlying luminescence phenomena have made it possible in recent decades to determine the age of a variety of materials important for quaternary geochronometry and archaeochronometry. We present a new luminescence dating method based on radioluminescence measurements of potassium feldspar. For the first time we have been able to investigate the light-emitting transition of electrons from the conduction band to an optically sensitive electron trap. Many advantages can be derived from such direct measurements of the metastable electron density in this particular trap, which produces the age-dependent signal. The method can be used to date the last light exposure of feldspar grains within a range of a few hundred to more than 200,000 years. Examples are presented of age determination of various waterlaid quaternary sands. The results of a basic study of feldspar radioluminescence also shed light on effects not sufficiently understood in conventional dating by luminescence techniques, especially in infrared optically stimulated luminescence dating of feldspar.

Der standige Radonfluβ vom Erdboden in die freie Atmosphare wird durch meteorologische Bedingungen beeinfluβt. Langzeitmessungen zeigen, daβ die Anderungen der Radonkonzentration (222Rn und 226Rn) in der Bodenluft mit Anderungen der Lufttemperatur korrelierbar sind. Es wird eine Beziehnng zur Temperaturkorrektion fur die geowissenschaflliche Prospektion angegeben.

Modulated metalorganic vapour phase epitaxial growth (MOVPE) is used to clarify the role of the surface conditions on the ordering behaviour in ternary (GaIn)P layers. The alternating deposition of GaP and InP layers with individual thicknesses of up to one monolayer is successfully used for the growth of (GaIn)P bulk layers lattice matched to (100) GaAs substrates with various off-orientations. The layer quality and the degree of ordering are investigated using high-resolution X-ray diffraction (XRD), transmission electron microscopy (TEM), and photoluminescence spectroscopy (PL), respectively. The application of modulated growth conditions for the deposition of (GaIn)P bulk layers has a strong influence on the degree of ordering achieved in the intermediate growth temperature regime where the highest degree of ordering occurs under continuous MOVPE. Beside a new boundary structure observed in layers grown under modulated flux conditions, the successful growth of highly ordered (GaIn)P layers grown using the modulated MOVPE technique support the model that up to 2 monolayers of the (GaIn)P growth surface are involved in the ordering formation process.

We present an X-ray diffraction (XRD) study of symmetrically strained superlattice structures with intentionally fluctuating individual layer thicknesses. Samples with periodic, aperiodic (random) and graded fluctuations have been realized by metalorganic vapor phase epitaxy (MOVPE). The precise structural properties of the disordered multilayer structures have been determined by high resolution XRD in combination with both kinematical as well as dynamical XRD theory. Periodic modulation of the compressive-strained (GaIn)As layers leads to peak splitting on the “tensile-strained” part of the XRD spectrum, while periodic variation of the tensile-strained Ga(PAs) layers results in splitting on the “compressive-strained” part. Aperiodic variation causes a broadening of the respective peaks. The study demonstrates the power of XRD to quantify fluctuations of layer thicknesses in the growth direction down to the monolayer level.

In this study, the use of novel, liquid, organic arsenic precursors as substitutes for the highly toxic hydride gas arsine (AsH3) in low pressure metalorganic vapor phase epitaxy (LP-MOVPE) of (GaIn)As lattice matched on InP has been investigated. The model precursors out of the classes of (alkyl)3-nAsHn(n= 0,1,2) are tertiarybutyl arsine (TBAs), ditertiarybutyl arsine (DitBAsH) and diethyltertiarybutyl arsine (DEtBAs). The MOVPE growth has been investigated in the temperature range of 570–650°C using VIIIratios from 2 to 20. The obtained epitaxial layer quality as examined by means of optical and scanning electron microscopy (SEM), high resolution double crystal X-ray diffraction, temperature-dependent van der Pauw-Hall, as well as photoluminescence (PL) measurements, will be compared for the different source molecules. Under optimized conditions almost uncompensated n-type (GaIn)As layers with carrier concentrations below 1 × 1015cm−3and corresponding mobilities above 80 000 cm2/V · s have been realized. For TBAs and DitBAsH in combination with the corresponding P sources TBP and DitBuPH, respectively, we have worked out a process parameter area for the growth of layers with device quality, as proven by the realization of a pin-detector structure.

Natural as well as 𝛾-induced thermoluminescence (TL) of Li-Fe-mica of tin-tungsten deposits of Ehrenfriedersdorf (Germany) and Zhanchivlan (Mongolia) were investigated. Natural TL allows to distinguish the samples of the two deposits in general. Artificial TL shows that the glow curves can be interpreted in terms of seven glow peaks. The formation of a kind of traps and their quantity reflected in the glow curves depends on the native rock. Kinetic parameters are given.